Merge branch 'feature/13' into dev

todo(13): done
test(handler): add tests for LocalStorageHandler
2026-03-14 05:02:56 +01:00 · 2026-03-14 05:02:55 +01:00 · 2026-03-14 04:57:32 +01:00 · 2026-03-14 04:55:37 +01:00 · 2026-03-14 04:39:24 +01:00 · 2026-03-14 04:34:13 +01:00
29 changed files with 4884 additions and 1445 deletions
--- a/.gitmodules
+++ b/.gitmodules
@ -0,0 +1,3 @@
 [submodule "vendor/tiara-gitflow-spec"]
 	path = vendor/tiara-gitflow-spec
 	url = git@bitbucket.org:byteb4rb1e/tiara-gitflow-spec.git
--- a/README.md
+++ b/README.md
@ -1,4 +1,89 @@
 # esm-logging
 A quasi-port of the Python standard library
 [logging](https://docs.python.org/3/library/logging.html) module to
 ECMAScript. Browser-compatible, zero dependencies.
-* [Logging Cookbook](doc/logging-cookbook.md)
+## Why?
 Logging is important. It is important for debugging purposes, leading to
 faster and more resilient development, for traceability leading to better
 security. Most logging libraries I've discovered didn't satisfy me, introduced
 weird concepts and all in all just weren't great. Other programming language
 ecosystems offer way nicer logging facilities. Take Rust for example, or...
 Python! Python has PEP, giving it a very structured approach towards
 implementing new features and that's also how its logging facilities came to be
 ([PEP 282](https://peps.python.org/pep-0282/)). Python's logging facilities
 are implemented by the [logging](https://docs.python.org/3/library/logging.html)
 module, which is part of the standard library and has been since 2002. It was
 originally authored by Vinay Sajip.
 ## Installation
 ```bash
 npm install @administratrix/esm-logging
 ```
 ## Quick start
 ```javascript
 import * as logging from '@administratrix/esm-logging';
 // one-shot configuration: sets up a console handler on the root logger
 logging.config.basicConfig({ level: logging.log_level.INFO });
 // create a logger for this module
 const logger = logging.manager.MANAGER.getLogger('myapp');
 logger.info('Application started');
 logger.warning('Something looks off');
 logger.error('Something went wrong');
 ```
 ## Concepts
 The logging system is built around four core components:
 - **Loggers** expose the interface that application code uses directly.
 - **Handlers** send log records to the appropriate destination (console,
  stderr, custom writable streams).
 - **Formatters** control the layout of log records in the final output.
 - **Filters** provide fine-grained control over which records to output.
 Loggers are organized in a dot-separated hierarchy. A logger named `app.db`
 is a child of the logger named `app`. Log records propagate up the hierarchy,
 so a handler attached to `app` will also receive records from `app.db`.
 ## Log levels
 | Constant   | Value | Purpose                                  |
 |------------|-------|------------------------------------------|
 | `CRITICAL` | 50    | A serious error, the program may not continue |
 | `ERROR`    | 40    | An error that prevented some operation   |
 | `WARNING`  | 30    | Something unexpected, but the software still works |
 | `INFO`     | 20    | Confirmation that things work as expected |
 | `DEBUG`    | 10    | Detailed diagnostic information          |
 | `NOTSET`   | 0     | All messages are processed               |
 ## Documentation
 See [docs/](docs/README.md) for the full user guide and
 [docs/logging-cookbook.md](docs/logging-cookbook.md) for recipes and patterns.
 API reference can be generated with TypeDoc:
 ```bash
 npm run build/doc
 ```
 ## Roadmap
 - [x] quasi-port of the logging module with minimal adaptation
 - [x] add documentation
 - [ ] add support for asynchronous calls
 - [ ] implement Open Cybersecurity Schema Framework (OCSF) formatter
 - [ ] implement browser local storage handler as a replacement for file handler
 ## License
 UNLICENSED
--- a/214
+++ b/214
@ -0,0 +1,214 @@
 --ISSUE
 Content-Type: application/issue
 ID: 1
 Type: feature
 Title: string formatting utilities
 Status: in-progress
 Priority: high
 Created: 2025-05-01
 Relationships:
 Description: implement utilities for formatting strings. The formatting should
             be inspired by Python 3K PEP 3101 in addition to their standard
             library utilities starting from ver. 3.7. Optimizations should
             focus on V8 support.
 --ISSUE
 Content-Type: application/issue
 ID: 2
 Type: feature
 Title: describe development workflow in CONTRIBUTING.md
 Status: open
 Priority: medium
 Created: 2025-05-01
 Relationships:
 Description: It's a good idea to describe the development workflow, including
             branching strategies earlier on, so that if someone is interested
             in forking, they can pick up right away. It's not meant for
             contributions though. I'm currently not interested in external
             contributions.
 --ISSUE
 Content-Type: application/issue
 ID: 3
 Type: bugfix
 Title: modularize testing further
 Status: done
 Priority: high
 Created: 2025-05-01
 Relationships:
 Description: Since I am going to implement unit tests as well as integration
             tests and probably some benchmarks, it makes sense to introduce
             another sub-level directory for each type of test, say
             tests/unit/, tests/integration, etc.
 --ISSUE
 Content-Type: application/issue
 ID: 4
 Type: feature
 Title: migrate testing framework from Jest to Mocha
 Status: in-progress
 Priority: high
 Created: 2025-05-01
 Relationships:
 Description: I really don't like behavior-driven testing, at least when it comes
             to unit testing. It feels like Walldorf education... Where I need
             to come up with an abstraction for describing my test. A function
             has an input and gives an output. That's what I want to test. I'm
             not trying to find the philosophical meaning of my functions...
             Hopefully Mocha is the savior. I'm sticking to xUnit based testing
             from now on.
 --ISSUE
 Content-Type: application/issue
 ID: 5
 Type: bugfix
 Title: fix critical bugs across core modules
 Status: done
 Priority: high
 Created: 2026-03-13
 Relationships:
 Description: multiple logic bugs prevent the library from functioning.
             manager.ts getLogger() has an inverted type check and missing
             return statement. config.ts basicConfig() assigns wrong option
             fields (filemode instead of datefmt/style) and has unreachable
             conditions. logger.ts isEnabledFor() always caches false,
             _log() never calls handle(), and makeRecord() uses .keys()
             instead of Object.keys(). handler.ts format() has no return
             statement and is missing a formatter getter.
 --ISSUE
 Content-Type: application/issue
 ID: 6
 Type: feature
 Title: implement remaining Logger level methods
 Status: done
 Priority: high
 Created: 2026-03-13
 Relationships: dependsOn:5
 Description: Logger only implements debug(). The info(), warning(), error(),
             and critical() methods are missing entirely. The _log() method
             also needs to be completed so it actually calls handle() after
             creating the LogRecord.
 --ISSUE
 Content-Type: application/issue
 ID: 7
 Type: feature
 Title: implement Formatter subsystem
 Status: done
 Priority: high
 Created: 2026-03-13
 Relationships: dependsOn:1
 Description: the three core Formatter methods are stubs returning placeholder
             strings. PercentFormatterStyle._format() needs to perform actual
             %-style field substitution against LogRecord attributes.
             Formatter.formatTime() needs a JS Date/Intl-based implementation
             replacing the Python time.strftime references.
             Formatter.formatError() needs to format Error.stack into a
             string. The datetime helper module is empty and needs time
             formatting utilities.
 --ISSUE
 Content-Type: application/issue
 ID: 8
 Type: feature
 Title: implement browser-compatible Handler output
 Status: done
 Priority: high
 Created: 2026-03-13
 Relationships: dependsOn:5
 Description: StreamHandler has no emit() implementation and its constructor
             ignores the stream parameter. The helper/stream module is a
             stub that needs a browser-compatible Writable interface backed
             by console output. FileHandler should be dropped or gated behind
             a Node.js environment check since browser environments have no
             filesystem write access. A ConsoleHandler targeting the browser
             console API (console.log/warn/error by level) is the primary
             output target.
 --ISSUE
 Content-Type: application/issue
 ID: 9
 Type: feature
 Title: implement Manager logger hierarchy
 Status: done
 Priority: high
 Created: 2026-03-13
 Relationships: dependsOn:5
 Description: Manager.getLogger() does not establish parent-child
             relationships between loggers based on dot-separated names.
             The Placeholder fixup logic is incomplete. Logger propagation
             depends on this hierarchy being correctly built so that child
             loggers forward records to parent handlers.
 --ISSUE
 Content-Type: application/issue
 ID: 10
 Type: feature
 Title: add documentation
 Status: done
 Priority: medium
 Created: 2026-03-13
 Relationships:
 Description: write user-facing documentation covering module usage, API
             reference, and configuration. The docs/ directory has stubs
             (README.md, logging-cookbook.md) that need to be fleshed out.
             TypeDoc generates API docs from source but a prose guide with
             examples is needed for onboarding.
 --ISSUE
 Content-Type: application/issue
 ID: 11
 Type: feature
 Title: add support for asynchronous calls
 Status: open
 Priority: low
 Created: 2026-03-13
 Relationships:
 Description: introduce async-aware logging so that handlers which perform
             I/O (e.g. network, storage) do not block the caller. This may
             involve an AsyncHandler base class or async emit() overloads,
             and consideration of how log record ordering is preserved
             across concurrent async contexts.
 --ISSUE
 Content-Type: application/issue
 ID: 12
 Type: feature
 Title: implement OCSF formatter
 Status: open
 Priority: low
 Created: 2026-03-13
 Relationships:
 Description: implement a Formatter subclass that outputs log records in
             Open Cybersecurity Schema Framework (OCSF) format. This
             enables structured security event logging compatible with
             SIEM systems and security analytics tooling.
 --ISSUE
 Content-Type: application/issue
 ID: 13
 Type: feature
 Title: implement browser local storage handler
 Status: done
 Priority: medium
 Created: 2026-03-13
 Relationships: dependsOn:8
 Description: implement a Handler subclass that persists log records to
             browser localStorage or IndexedDB as a replacement for
             FileHandler in browser environments. Should support log
             rotation by size or entry count to avoid exceeding storage
             quotas.
--- a/bitbucket-pipelines.yml
+++ b/bitbucket-pipelines.yml
@ -26,6 +26,7 @@ definitions:
                - build/debug/**/*
                - build/debug/*
            script:
                - make clean
                - make build/debug CI=1
        - step: &build-release
            name: Build (Release)
@ -35,6 +36,7 @@ definitions:
                - build/release/**/*
                - build/release/*
            script:
                - make clean
                - make build/release CI=1
        - step: &build-doc
            name: Build (Doc)
@ -44,6 +46,7 @@ definitions:
                - build/doc/**/*
                - build/doc/*
            script:
                - make clean
                - make build/doc CI=1
        - step: &dist
            name: Package
@ -52,6 +55,7 @@ definitions:
            artifacts:
                - dist/*
            script:
                - rm -rvf test-reports/
                - make dist CI=1
 pipelines:
    default:
--- a/docs/README.md
+++ b/docs/README.md
@ -1 +1,333 @@
-The doc/README.md
+# esm-logging user guide
 This guide covers the `@administratrix/esm-logging` library, a quasi-port of
 Python's `logging` module for ECMAScript. It targets browser environments and
 provides hierarchical, configurable logging with formatters, handlers, and
 filters.
 ## Table of contents
 - [Basic usage](#basic-usage)
 - [Loggers](#loggers)
 - [Handlers](#handlers)
 - [Formatters](#formatters)
 - [Filters](#filters)
 - [Configuration](#configuration)
 - [Log record attributes](#log-record-attributes)
 ## Basic usage
 The simplest way to start logging is with `basicConfig`:
 ```javascript
 import * as logging from '@administratrix/esm-logging';
 logging.config.basicConfig({
    level: logging.log_level.DEBUG,
    format: '%(levelname)s:%(name)s:%(message)s',
 });
 const logger = logging.manager.MANAGER.getLogger('myapp');
 logger.info('Hello, world');
 // output: INFO:myapp:Hello, world
 ```
 `basicConfig` creates a `StreamHandler` writing to stderr (via
 `console.error`) and attaches it to the root logger. It is a one-shot
 function: calling it again has no effect unless you pass `force: true`.
 ## Loggers
 Loggers are the entry point for emitting log records. They are organized in a
 dot-separated hierarchy managed by a singleton `Manager`.
 ### Creating loggers
 ```javascript
 const logger = logging.manager.MANAGER.getLogger('myapp');
 const childLogger = logging.manager.MANAGER.getLogger('myapp.db');
 ```
 Calling `getLogger` with the same scope always returns the same logger
 instance. The hierarchy is established automatically: `myapp.db` is a child of
 `myapp`.
 ### Setting levels
 ```javascript
 logger.setLevel(logging.log_level.WARNING);
 ```
 A logger only processes messages at or above its effective level. The
 effective level is determined by walking up the parent chain until a logger
 with a non-zero level is found. The root logger defaults to `WARNING`.
 ### Logging methods
 Each level has a corresponding method:
 ```javascript
 logger.debug('Detailed diagnostic info');
 logger.info('Things are working');
 logger.warning('Something unexpected');
 logger.error('An operation failed');
 logger.critical('System is in trouble');
 ```
 ### Propagation
 By default, log records propagate up the hierarchy. A record emitted by
 `myapp.db` will be handled by handlers on `myapp.db`, then `myapp`, then the
 root logger. This means you typically only need to configure handlers on the
 root logger or on high-level loggers.
 ### Checking if a level is enabled
 ```javascript
 if (logger.isEnabledFor(logging.log_level.DEBUG)) {
    logger.debug('Expensive computation: ' + computeDebugInfo());
 }
 ```
 This avoids the cost of building the message string when the level would be
 filtered out anyway.
 ## Handlers
 Handlers determine where log records go. A logger can have multiple handlers,
 and each handler can have its own level and formatter.
 ### Available handlers
 #### StreamHandler
 Writes formatted output to a `Writable` stream. Defaults to stderr (via
 `console.error`).
 ```javascript
 import { StreamHandler } from '@administratrix/esm-logging/src/handler';
 import { ConsoleWritable } from '@administratrix/esm-logging/src/helper/stream';
 const handler = new StreamHandler(new ConsoleWritable());
 logger.addHandler(handler);
 ```
 #### ConsoleHandler
 Maps log levels to the appropriate browser console method:
 - `ERROR` and `CRITICAL` use `console.error`
 - `WARNING` uses `console.warn`
 - `DEBUG` and `INFO` use `console.log`
 ```javascript
 import { ConsoleHandler } from '@administratrix/esm-logging/src/handler';
 const handler = new ConsoleHandler();
 handler.level = logging.log_level.DEBUG;
 logger.addHandler(handler);
 ```
 #### StderrHandler
 Always writes to `console.error`, regardless of level. Useful when you want
 all output on stderr.
 ```javascript
 import { StderrHandler } from '@administratrix/esm-logging/src/handler';
 const handler = new StderrHandler(logging.log_level.WARNING);
 logger.addHandler(handler);
 ```
 #### FileHandler
 Not available in browser environments. Throws `NotImplementedError` on
 construction. Use `ConsoleHandler` or a storage-backed handler instead.
 ### Handler methods
 ```javascript
 handler.level = logging.log_level.INFO;  // only handle INFO and above
 handler.formatter = myFormatter;         // set a custom formatter
 handler.close();                         // release resources
 ```
 ### Custom handlers
 Subclass `Handler` and implement `emit(record)`:
 ```javascript
 import { Handler } from '@administratrix/esm-logging/src/handler';
 class ArrayHandler extends Handler {
    constructor() {
        super();
        this.records = [];
    }
    emit(record) {
        this.records.push(this.format(record));
    }
 }
 ```
 ## Formatters
 Formatters control how log records are rendered as strings. The default format
 is `%(message)s` (just the message). The basic format used by `basicConfig` is
 `%(levelname)s:%(name)s:%(message)s`.
 ### Creating a formatter
 ```javascript
 import { Formatter } from '@administratrix/esm-logging/src/formatter';
 const formatter = new Formatter({
    fmt: '%(asctime)s - %(levelname)s - %(name)s - %(message)s',
    datefmt: '%Y-%m-%d %H:%M:%S',
 });
 handler.formatter = formatter;
 ```
 ### Format string placeholders
 Formatters use `%`-style substitution. Available placeholders correspond to
 [log record attributes](#log-record-attributes):
 ```
 %(name)s        Logger scope name
 %(levelno)d     Numeric log level
 %(levelname)s   Text log level (DEBUG, INFO, etc.)
 %(message)s     The formatted message
 %(asctime)s     Human-readable timestamp
 %(created)f     Milliseconds since epoch (Date.now())
 ```
 ### Date formatting
 The `datefmt` option accepts strftime-style tokens:
 | Token | Meaning         | Example |
 |-------|-----------------|---------|
 | `%Y`  | Four-digit year | 2026    |
 | `%m`  | Zero-padded month | 03    |
 | `%d`  | Zero-padded day | 14      |
 | `%H`  | Hour (24h)      | 09      |
 | `%M`  | Minute          | 05      |
 | `%S`  | Second          | 30      |
 If `datefmt` is omitted, an ISO 8601-like format is used:
 `2026-03-14 09:05:30.123`.
 ## Filters
 Filters provide fine-grained control over which records get processed. They
 can be attached to loggers or handlers.
 ### Scope-based filtering
 A `Filter` initialized with a scope name only allows records from that scope
 and its children:
 ```javascript
 import { Filter } from '@administratrix/esm-logging/src/filter';
 const filter = new Filter('myapp.db');
 handler.addFilter(filter);
 // only records from 'myapp.db' and 'myapp.db.*' will pass
 ```
 A filter initialized with an empty string allows all records.
 ### Custom filters
 Any object with a `filter(record)` method can be used:
 ```javascript
 handler.addFilter({
    filter(record) {
        return record.levelno >= logging.log_level.WARNING;
    }
 });
 ```
 ## Configuration
 ### basicConfig
 `basicConfig` is a convenience function for simple, one-shot configuration of
 the root logger:
 ```javascript
 logging.config.basicConfig({
    level: logging.log_level.DEBUG,
    format: '%(asctime)s %(levelname)s %(message)s',
    datefmt: '%Y-%m-%d %H:%M:%S',
 });
 ```
 #### Options
 | Option     | Type       | Description                                |
 |------------|------------|--------------------------------------------|
 | `level`    | `number`   | Root logger level                          |
 | `format`   | `string`   | Format string for the handler's formatter  |
 | `datefmt`  | `string`   | Date format string                         |
 | `style`    | `string`   | Format style (`'%'` only, currently)       |
 | `handlers` | `Handler[]`| Pre-built handlers to attach               |
 | `stream`   | `Writable` | Stream for the default StreamHandler       |
 | `force`    | `boolean`  | Remove existing handlers first             |
 `stream` and `handlers` are mutually exclusive.
 ### Manual configuration
 For more control, configure loggers and handlers directly:
 ```javascript
 const root = logging.manager.MANAGER.root;
 const handler = new ConsoleHandler();
 handler.level = logging.log_level.DEBUG;
 handler.formatter = new Formatter({
    fmt: '%(asctime)s [%(levelname)s] %(name)s: %(message)s',
 });
 root.addHandler(handler);
 root.setLevel(logging.log_level.DEBUG);
 ```
 ## Log record attributes
 A `LogRecord` carries the following attributes:
 | Attribute   | Type     | Description                            |
 |-------------|----------|----------------------------------------|
 | `scope`     | `string` | Logger name that created the record    |
 | `name`      | `string` | Same as `scope`                        |
 | `levelno`   | `number` | Numeric level (10, 20, 30, 40, 50)    |
 | `levelname` | `string` | Text level (`DEBUG`, `INFO`, etc.)     |
 | `msg`       | `string` | The raw message template               |
 | `args`      | `any[]`  | Substitution arguments for `%s` in msg |
 | `message`   | `string` | The formatted message (set by formatter) |
 | `created`   | `number` | Milliseconds since Unix epoch          |
 | `asctime`   | `string` | Formatted timestamp (set by formatter) |
 The `getMessage()` method on `LogRecord` performs `%s` argument substitution
 on `msg` using `args`.
 ## Module structure
 The library is organized into submodules, all re-exported from the main entry
 point:
 | Import path   | Contents                                     |
 |---------------|----------------------------------------------|
 | `config`      | `basicConfig()`                              |
 | `filter`      | `Filter`, `Filterer`                         |
 | `formatter`   | `Formatter`, `STYLES`, `DEFAULT_FORMATTER`   |
 | `handler`     | `Handler`, `StreamHandler`, `ConsoleHandler`, `StderrHandler`, `FileHandler` |
 | `log_level`   | Level constants, `getLevelName()`, `checkLevel()` |
 | `log_record`  | `LogRecord`, factory functions               |
 | `logger`      | `Logger`, `RootLogger`, `ROOT`               |
 | `manager`     | `Manager`, `MANAGER`                         |
--- a/docs/logging-cookbook.md
+++ b/docs/logging-cookbook.md
@ -1,37 +1,216 @@
-# Using logging in multiple modules
+# Logging cookbook
-Multiple calls to `logging.getLogger('someLogger')` return a reference to the
+Recipes and patterns for common logging tasks with `@administratrix/esm-logging`.
 same logger object. This is true not only within the same module, but also
 across modules as long as it is in the same Python interpreter process. It is
 true for references to the same object; additionally, application code can
 define and configure a parent logger in one module and create (but not
 configure) a child logger in a separate module, and all logger calls to the
 child will pass up to the parent. Here is a main module:
-``javascript
+## Using logging across multiple modules
 import * as logging from 'eslib/logging';
 import * as my_module from './my_module';
-// create logger with 'spam_application'
+`getLogger` returns the same logger instance for a given scope name across
-var logger = logging.getLogger('spam_application');
+your entire application. Configure handlers on a parent logger and create
-logger.setLevel(logging.DEBUG);
+child loggers in each module:
-// create file handler which logs even debug messages
+```javascript
-var fh = logging.FileHandler('spam.log')
+// main.js
-fh.setLevel(logging.DEBUG);
+import * as logging from '@administratrix/esm-logging';
 import { ConsoleHandler } from '@administratrix/esm-logging/src/handler';
 import { Formatter } from '@administratrix/esm-logging/src/formatter';
 import { doWork } from './worker.js';
-// create console handler with a higher log level
+const logger = logging.manager.MANAGER.getLogger('myapp');
-var ch = logging.StreamHandler();
+logger.setLevel(logging.log_level.DEBUG);
 ch.setLevel(logging.ERROR);
-// create formatter and add it to the handlers
+const handler = new ConsoleHandler();
-var formatter = logging.Formatter('%(asctime)s - %(name)s - %(levelname)s - %(message)s');
+handler.level = logging.log_level.DEBUG;
-fh.setFormatter(formatter);
+handler.formatter = new Formatter({
-ch.setFormatter(formatter);
+    fmt: '%(asctime)s - %(name)s - %(levelname)s - %(message)s',
 });
 logger.addHandler(handler);
-// add the handlers to the logger
+logger.info('Application starting');
-logger.addHandler(fh);
+doWork();
-logger.addHandler(ch);
+logger.info('Application finished');
 logger.info('creating an instance of auxiliary_module.Auxiliary')
 ```
 ```javascript
 // worker.js
 import * as logging from '@administratrix/esm-logging';
 const logger = logging.manager.MANAGER.getLogger('myapp.worker');
 export function doWork() {
    logger.debug('Starting work');
    // ... do something ...
    logger.info('Work completed');
 }
 ```
 Because `myapp.worker` is a child of `myapp`, its records propagate up to the
 handler configured on `myapp`. No handler configuration is needed in
 `worker.js`.
 Output:
 ```
 2026-03-14 10:00:00.000 - myapp - INFO - Application starting
 2026-03-14 10:00:00.001 - myapp.worker - DEBUG - Starting work
 2026-03-14 10:00:00.002 - myapp.worker - INFO - Work completed
 2026-03-14 10:00:00.003 - myapp - INFO - Application finished
 ```
 ## Logging to multiple destinations
 Attach multiple handlers to a single logger, each with its own level and
 formatter:
 ```javascript
 import * as logging from '@administratrix/esm-logging';
 import { ConsoleHandler, StderrHandler } from '@administratrix/esm-logging/src/handler';
 import { Formatter } from '@administratrix/esm-logging/src/formatter';
 const logger = logging.manager.MANAGER.getLogger('myapp');
 logger.setLevel(logging.log_level.DEBUG);
 // console handler: shows everything with detailed format
 const consoleHandler = new ConsoleHandler();
 consoleHandler.level = logging.log_level.DEBUG;
 consoleHandler.formatter = new Formatter({
    fmt: '%(asctime)s [%(levelname)s] %(name)s: %(message)s',
 });
 logger.addHandler(consoleHandler);
 // stderr handler: only errors, compact format
 const errorHandler = new StderrHandler(logging.log_level.ERROR);
 errorHandler.formatter = new Formatter({
    fmt: 'ERROR %(asctime)s %(name)s: %(message)s',
    datefmt: '%Y-%m-%d %H:%M:%S',
 });
 logger.addHandler(errorHandler);
 ```
 ## Using basicConfig for simple scripts
 For quick scripts, `basicConfig` sets up a handler on the root logger:
 ```javascript
 import * as logging from '@administratrix/esm-logging';
 logging.config.basicConfig({
    level: logging.log_level.INFO,
    format: '%(levelname)s: %(message)s',
 });
 const logger = logging.manager.MANAGER.getLogger('script');
 logger.info('Running');
 logger.warning('Check this');
 ```
 Output:
 ```
 INFO: Running
 WARNING: Check this
 ```
 ## Filtering records
 ### By scope
 Only allow records from a specific part of the hierarchy:
 ```javascript
 import { Filter } from '@administratrix/esm-logging/src/filter';
 const dbFilter = new Filter('myapp.db');
 handler.addFilter(dbFilter);
 // handler now only processes records from 'myapp.db' and its children
 ```
 ### By custom criteria
 Use any object with a `filter(record)` method:
 ```javascript
 handler.addFilter({
    filter(record) {
        // only pass records that contain 'important' in the message
        return record.msg.includes('important');
    }
 });
 ```
 ## Custom formatters
 Create formatters with different format strings for different contexts:
 ```javascript
 import { Formatter } from '@administratrix/esm-logging/src/formatter';
 // detailed format for development
 const devFormatter = new Formatter({
    fmt: '%(asctime)s %(levelname)s %(name)s: %(message)s',
    datefmt: '%H:%M:%S',
 });
 // compact format for production
 const prodFormatter = new Formatter({
    fmt: '%(levelname)s:%(name)s:%(message)s',
 });
 ```
 ## Custom handlers
 Subclass `Handler` and implement `emit(record)`:
 ```javascript
 import { Handler } from '@administratrix/esm-logging/src/handler';
 class BufferHandler extends Handler {
    constructor(level) {
        super(level);
        this.buffer = [];
    }
    emit(record) {
        try {
            this.buffer.push(this.format(record));
            if (this.buffer.length >= 100) {
                this.flush();
            }
        } catch (e) {
            this.handleError(record);
        }
    }
    flush() {
        // send buffered records somewhere
        const batch = this.buffer.splice(0);
        // ... process batch ...
    }
 }
 ```
 ## Disabling logging below a threshold
 The manager's `disable` property suppresses all logging at or below a given
 level across all loggers:
 ```javascript
 import * as logging from '@administratrix/esm-logging';
 // suppress DEBUG and INFO globally
 logging.manager.MANAGER.disable = logging.log_level.INFO;
 ```
 ## Reconfiguring with force
 `basicConfig` only takes effect once. To reconfigure, use `force: true`:
 ```javascript
 logging.config.basicConfig({
    level: logging.log_level.DEBUG,
    format: '%(asctime)s %(message)s',
    force: true,
 });
 ```
 This removes and closes all existing handlers on the root logger before
 applying the new configuration.
--- a/eslint.config.mjs
+++ b/eslint.config.mjs
@ -0,0 +1,7 @@
 import eslint from "@eslint/js";
 import tseslint from "typescript-eslint";
 export default tseslint.config(
    eslint.configs.recommended,
    tseslint.configs.recommended,
 );
--- a/jest.config.mjs
+++ b/jest.config.mjs
@ -19,5 +19,5 @@ export default {
            }
        ],
    ],
-    roots: ['./tests']
+    roots: ['./tests/unit']
 }
--- a/package-lock.json
+++ b/package-lock.json
--- a/package.json
+++ b/package.json
@ -1,16 +1,17 @@
 {
-    "name": "administratrix/esm-logging",
+    "name": "@administratrix/esm-logging",
    "version": "1.0.0",
    "description": "port of Python standard library logging module",
    "main": "lib/index.js",
    "engines": {
        "node": ">= 20.11.0"
    },
    "scripts": {
-        "test": "jest",
+        "build/debug": "tsc -p tsconfig.debug.json",
-        "build": "npm run build:release",
+        "build/release": "tsc",
-        "build:release": "tsc",
+        "build/doc": "typedoc",
-        "build:debug": "tsc -p tsconfig.debug.json",
+        "dist": "ts-node -P tsconfig.node.json scripts/npm-pack.ts build/release dist",
-        "doc": "typedoc --entryPoints src/index.ts --html build/doc",
+        "test-reports/unit": "jest"
        "publish_": "ts-node -P tsconfig.node.json scripts/publish.ts",
        "dist": "ts-node -P tsconfig.node.json scripts/npm-pack.ts build/release dist"
    },
    "repository": {
        "type": "git",
@ -19,13 +20,16 @@
    "author": "Tiara Rodney",
    "license": "UNLICENSED",
    "devDependencies": {
        "@eslint/js": "^9.39.4",
        "@types/jest": "^29.5.14",
        "eslint": "^9.39.4",
        "jest": "^29.7.0",
        "jest-junit": "^16.0.0",
        "ts-jest": "^29.3.2",
        "ts-node": "^10.9.2",
-        "typedoc": "^0.27.9",
+        "typedoc": "^0.28.3",
-        "typescript": "^5.8.3"
+        "typescript": "^5.8.3",
        "typescript-eslint": "^8.57.0"
    },
    "overrides": {
        "jest": {
--- a/src/config.ts
+++ b/src/config.ts
@ -0,0 +1,192 @@
 import { MANAGER } from './manager';
 import { ValueError } from './helper/error';
 import { STYLES, Formatter } from './formatter';
 import { StreamHandler, FileHandler, Handler } from './handler';
 import { LogLevel } from './log-level';
 //---------------------------------------------------------------------------
 // Configuration classes and functions
 //---------------------------------------------------------------------------
 /**
 * options for basic configuration of logging module
 */
 export interface BasicConfigOptions {
    /*
     * Specifies that a FileHandler be created, using the specified filename,
     * rather than a StreamHandler.
     */
    filename?: string;
    /**
     * Specifies the mode to open the file, if filename is specified (if
     * filemode is unspecified, it defaults to 'a')
     */
    filemode?: string;
    /**
     * Use the specified format string for the handler.
     */
    format?: string;
    /**
     * Use the specified date/time format.
     *
     */
    datefmt?: string;
    /**
     * If a format string is specified, use this to specify the type of format
     * string (possible values '%', '{', '$', for %-formatting,
     * :meth:`str.format` and :class:`string.Template`- defaults to '%').
     *
     * TODO: switch to enum
     */
    style?: string;
    /**
     * Set the root logger level to the specified level.
     */
    level?: LogLevel;
    /**
     * Use the specified stream to initialize the StreamHandler.  Note that this
     * argument is incompatible with 'filename' - if both are present, 'stream'
     * is ignored.
     *
     * TODO:
     */
    stream?: any;
    /**
     * If specified, this should be an iterable of already created handlers,
     * which will be added to the root logger. Any handler in the list which
     * does not have a formatter assigned will be assigned the formatter created
     * in this function.
     */
    handlers?: Handler[];
    /**
     * If this keyword  is specified as true, any existing handlers attached to
     * the root logger are removed and closed, before carrying out the
     * configuration as specified by the other arguments.
     */
    force?: boolean;
    /**
     * If specified together with a filename, this encoding is passed to the
     * created FileHandler, causing it to be used when the file is opened.
     */
    encoding?: string;
    /**
     * If specified together with a filename, this value is 
     * passed to the created FileHandler, causing it to be used 
     * when the file is opened in text mode. If not specified, 
     * the default value is `backslashreplace`.
     */
    errors?: string|null;
 }
 /**
 * Do basic configuration for the logging system.
 *
 * This function does nothing if the root logger already has handlers
 * configured, unless the keyword argument *force* is set to ``True``.
 * It is a convenience method intended for use by simple scripts
 * to do one-shot configuration of the logging package.
 *
 * The default behaviour is to create a StreamHandler which writes to
 * sys.stderr, set a formatter using the BASIC_FORMAT format string, and
 * add the handler to the root logger.
 *
 * A number of optional keyword arguments may be specified, which can alter
 * the default behaviour.
 *
 * Note that you could specify a stream created using open(filename, mode)
 * rather than passing the filename and mode in. However, it should be
 * remembered that StreamHandler does not close its stream (since it may be
 * using sys.stdout or sys.stderr), whereas FileHandler closes its stream
 * when the handler is closed.
 *
 * TODO: refactor logic, there apparently is some redundancy in the original
 *       code
 */
 export function basicConfig(options: BasicConfigOptions) {
    const force = options.force ?? false;
    var encoding = options.encoding ?? undefined;
    var errors: string|undefined = options.errors ?? 'backslashreplace';
    var handlers = options.handlers ?? [];
    const filename = options.filename ?? null;
    const stream = options.stream ?? null;
    const filemode = options.filemode ?? 'a';
    const dateformat = options.datefmt;
    const style = options.style ?? '%';
    const level = options.level ?? null;
    if (!Object.keys(STYLES).includes(style)) {
        throw new ValueError(
            `style must be one of: ${Object.keys(STYLES).join(', ')}`
        );
    }
    if (force) {
        for (var i = 0; i < MANAGER.root.handlers.length; i += 1) {
            let h: Handler = MANAGER.root.handlers[i];
            MANAGER.root.removeHandler(h);
            h.close();
        }
    }
    if (MANAGER.root.handlers.length > 0 && !force) {
        return;
    }
    if (handlers.length > 0) {
        if (stream || filename) {
            throw new ValueError(
                "'stream' or 'filename' should not be specified together " +
                "with 'handlers'"
            );
        }
    }
    else {
        if (stream && filename) {
            throw new ValueError(
                "'stream' and 'filename' should not be specified together"
            );
        }
        if (filename) {
            if (filemode.match('b')) { errors = undefined }
            else { encoding = 'utf-8' }
            handlers = [new FileHandler({
                filename: filename,
                filemode: filemode,
                encoding: encoding,
                errors: errors
            })];
        }
        else {
            handlers = [new StreamHandler(stream)];
        }
    }
    for (let i = 0; i < handlers.length; i += 1) {
        const h = handlers[i];
        if (h.formatter === null) {
            h.formatter = new Formatter({
                fmt: options.format ?? STYLES[style][1],
                datefmt: dateformat,
                style: style
            });
        }
        MANAGER.root.addHandler(h);
    }
    if (level !== null) { MANAGER.root.setLevel(level) }
 }
--- a/src/filter.ts
+++ b/src/filter.ts
@ -0,0 +1,114 @@
 import { LogRecord } from './log-record';
 //---------------------------------------------------------------------------
 // Filter classes and functions
 //---------------------------------------------------------------------------
 export type FilterCallable = (record: LogRecord) => boolean;
 /**
 * Filter instances are used to perform arbitrary filtering of LogRecords.
 *
 * Loggers and Handlers can optionally use Filter instances to filter records as
 * desired. The base filter class only allows events which are below a certain
 * point in the logger hierarchy. For example, a filter initialized with "A.B"
 * will allow events logged by loggers "A.B", initialized with the empty string,
 * all events are passed.
 */
 export class Filter {
    public readonly scope: string;
    public readonly slen: number;
    /**
     * Initialize with the name of the logger which ,together with its children,
     * will have its events allowed through the filter. If no name is specified,
     * allow every event.
     *
     * @param name - name of logging scope
     */
    constructor(scope: string) {
        this.scope = scope ?? '';
        this.slen = this.scope.length;
    }
    /**
     * Inspect a record, if it should be logged.
     *
     * Returns true if the record should be logged, or false otherwise. If
     * deemed appropriate, the record may be modified in-place.
     *
     * @param - scope of log record to inspect
     * @param - log record to inspect
     */
    filter(record: LogRecord): boolean {
        if (this.slen == 0 || this.scope == record.scope) { return true }
        else if (!record.scope.substring(0, this.slen)) { return false }
        return (record.scope[this.slen] == '.')
    }
 }
 export class Filterer {
    filters: Filter[] = [];
    /**
     * Add the specified filter to this handler.
     *
     * @param filter
     */
    addFilter(filter: Filter) {
        if (!this.filters.includes(filter)) { this.filters.push(filter) }
    }
    /**
     * Remove the specified filter from this handler.
     *
     * @param filter
     */
    removeFilter(filter: Filter) {
        if (this.filters.includes(filter)) {
            this.filters.splice(this.filters.indexOf(filter), 1)
        }
    }
    /**
     * Determine if a record is loggable by consulting all the filters.
     *
     * The default is to allow the record to be logged; any filter can veto this
     * by returning a false value.
     * If a filter attached to a handler returns a log record instance, then
     * that instance is used in place of the original log record in any further
     * processing of the event by that handler.
     * If a filter returns any other true value, the original log record is used
     * in any further processing of the event by that handler.
     *
     * If none of the filters return false values, this method returns a log
     * record.
     *
     * If any of the filters return a false value, this method returns a false
     * value.
     *
     * @param filter
     */
    filter(record: LogRecord): LogRecord|null {
        for (var i = 0; i < this.filters.length; i += 1) {
            let result: boolean|LogRecord = false;
            let filter = this.filters[i];
            if (typeof (filter as Filter).filter == 'function') {
                result = (filter as Filter).filter(record)
            }
            else {
                result = (filter as unknown as FilterCallable)(record)
            }
            if (!result) { return null }
            if ((result as any) instanceof LogRecord) { record = result as unknown as LogRecord }
        }
        return record
    }
 }
--- a/src/formatter.ts
+++ b/src/formatter.ts
@ -0,0 +1,217 @@
 import { MyError, ValueError } from './helper/error';
 import { LogRecord } from './log-record';
 //---------------------------------------------------------------------------
 // Formatter classes and functions
 //---------------------------------------------------------------------------
 export interface PercentFormatterStyleOptions {
    fmt?: string,
    defaults: {[key: string]: any};
 }
 /**
 * %-style formatting for log records.
 *
 * Substitutes %(name)s, %(name)d, %(name)f placeholders from record
 * attributes.
 */
 class PercentFormatterStyle {
    public static defaultFormat = '%(message)s';
    public static asctimeFormat = '%(asctime)s';
    public static asctimeSearch = '%(asctime)';
    public static validationPattern =
        /%\(\w+\)[#0+ -]*(\*|\d+)?(\.(\*|\d+))?[diouxefgcrsa%]/;
    public fmt: string;
    private defaults: {[key: string]: any};
    constructor(options: PercentFormatterStyleOptions) {
        this.fmt = options.fmt ?? PercentFormatterStyle.defaultFormat;
        this.defaults = options.defaults;
    }
    usesTime(): boolean {
        return this.fmt.indexOf(PercentFormatterStyle.asctimeSearch) >= 0;
    }
    /**
     * Validate the input format, ensure it matches the correct style
     */
    validate() {
        if (!PercentFormatterStyle.validationPattern.test(this.fmt)) {
            throw new ValueError(
                `Invalid format '${this.fmt}' for ` +
                `'${PercentFormatterStyle.defaultFormat[0]}'`
            )
        }
    }
    protected _format(record: LogRecord): string {
        const values: {[key: string]: any} = {
            ...this.defaults,
            ...(record as unknown as {[key: string]: any}),
        };
        return this.fmt.replace(
            /%\((\w+)\)([#0+ -]*(?:\*|\d+)?(?:\.(?:\*|\d+))?[diouxefgcrsa%])/g,
            (_match, key, spec) => {
                if (!(key in values)) {
                    throw new ValueError(`formatting field not found in record: ${key}`);
                }
                const val = values[key];
                const conversion = spec[spec.length - 1];
                switch (conversion) {
                    case 'd':
                    case 'i':
                        return String(Math.floor(Number(val)));
                    case 'f':
                        return String(Number(val));
                    case 's':
                        return String(val);
                    default:
                        return String(val);
                }
            }
        );
    }
    format(record: LogRecord): string {
        try {
            return this._format(record)
        }
        catch (e) {
            if (e instanceof ValueError) { throw e }
            throw new ValueError(`formatting field not found in record: ${e}`)
        }
    }
 }
 const BASIC_FORMAT = '%(levelname)s:%(name)s:%(message)s';
 export const STYLES: {[key: string]: [{ new(options: PercentFormatterStyleOptions): PercentFormatterStyle}, string]} = {
    '%': [PercentFormatterStyle, BASIC_FORMAT],
 }
 export interface FormatterOptions {
    fmt?: string
    datefmt?: string
    style?: string
    validate?: boolean
    defaults?: {[key: string]: any}
 }
 /**
 * Formatter instances are used to convert a LogRecord to text.
 *
 * Formatters need to know how a LogRecord is constructed. They are
 * responsible for converting a LogRecord to (usually) a string which can
 * be interpreted by either a human or an external system. The base Formatter
 * allows a formatting string to be specified. If none is supplied, the
 * style-dependent default value, "%(message)s", "{message}", or
 * "${message}", is used.
 *
 * The Formatter can be initialized with a format string which makes use of
 * knowledge of the LogRecord attributes - e.g. the default value mentioned
 * above makes use of the fact that the user's message and arguments are pre-
 * formatted into a LogRecord's message attribute. Currently, the useful
 * attributes in a LogRecord are described by:
 *
 * %(name)s            Name of the logger (logging channel)
 * %(levelno)s         Numeric logging level for the message (DEBUG, INFO,
 *                     WARNING, ERROR, CRITICAL)
 * %(levelname)s       Text logging level for the message ("DEBUG", "INFO",
 *                     "WARNING", "ERROR", "CRITICAL")
 * %(created)f         Time when the LogRecord was created (Date.now()
 *                     return value)
 * %(asctime)s         Textual time when the LogRecord was created
 * %(message)s         The result of record.getMessage(), computed just as
 *                     the record is emitted
 */
 export class Formatter {
    public static defaultTimeFormat = 'YYYY-MM-DDTHH:mm:ss';
    public static defaultMsecFormat = '%s.%03d';
    protected style: PercentFormatterStyle;
    protected fmt: string;
    protected datefmt: string|undefined;
    constructor(options?: FormatterOptions) {
        options = options ?? {};
        const style = options.style ?? '%';
        const validate = options.validate ?? true;
        if (!Object.keys(STYLES).includes(style)) {
            throw new ValueError(`style must be one of: ${Object.keys(STYLES).join(', ')}`)
        }
        this.style = new STYLES[style][0]({
            fmt: options.fmt,
            defaults: options.defaults ?? {}
        });
        if (validate) { this.style.validate() }
        this.fmt = this.style.fmt;
        this.datefmt = options.datefmt;
    }
    usesTime(): boolean {
        return this.style.usesTime();
    }
    /**
     * Format the specified record as text.
     *
     * The record's attribute dictionary is used as the operand to a string
     * formatting operation which yields the returned string. Before the
     * formatting operation, a couple of preparatory steps are carried out.
     * The message attribute of the record is computed using LogRecord.getMessage().
     * If the formatting string uses the time, formatTime() is called to format
     * the event time.
     */
    format(record: LogRecord): string {
        record.message = record.getMessage();
        if (this.usesTime()) {
            record.asctime = this.formatTime(record, this.datefmt);
        }
        return this.style.format(record);
    }
    /**
     * Return the creation time of the specified LogRecord as formatted text.
     *
     * If datefmt is specified, it is used as a strftime-style format string.
     * Supported tokens: %Y, %m, %d, %H, %M, %S.
     * Otherwise, an ISO8601-like format is used.
     */
    formatTime(record: LogRecord, datefmt?: string): string {
        const dt = new Date(record.created);
        if (datefmt) {
            return datefmt
                .replace('%Y', String(dt.getFullYear()))
                .replace('%m', String(dt.getMonth() + 1).padStart(2, '0'))
                .replace('%d', String(dt.getDate()).padStart(2, '0'))
                .replace('%H', String(dt.getHours()).padStart(2, '0'))
                .replace('%M', String(dt.getMinutes()).padStart(2, '0'))
                .replace('%S', String(dt.getSeconds()).padStart(2, '0'));
        }
        const iso = dt.toISOString();
        return iso.replace('T', ' ').replace('Z', '');
    }
    /**
     * Format and return the specified exception information as a string.
     */
    formatError(ei: MyError): string {
        if (ei.stack) { return ei.stack }
        return String(ei);
    }
 }
 export const DEFAULT_FORMATTER = new Formatter();
--- a/src/handler.ts
+++ b/src/handler.ts
@ -0,0 +1,347 @@
 import { LogLevel, checkLevel, NOTSET, WARNING, ERROR } from './log-level';
 import { LogRecord } from './log-record';
 import { Formatter, DEFAULT_FORMATTER } from './formatter';
 import { Filterer } from './filter';
 import { NotImplementedError } from './helper/error';
 import { Writable, DEFAULT_STREAM, StderrWritable } from './helper/stream';
 //---------------------------------------------------------------------------
 // Handler classes and functions
 //----------------------------------------------------------------------------
 type Handlers = {[key: string]: Handler};
 /**
 * map of handler names to handlers
 */
 const HANDLERS: Handlers = {};
 /**
 * added to allow handlers to be removed in reverse order of initialization
 */
 const HANDLER_LIST: WeakRef<Handler>[] = [];
 /**
 * Add a handler to the internal cleanup list using a weak reference.
 *
 * @param handler -
 */
 function addHandlerRef(handler: Handler) {
    HANDLER_LIST.push(new WeakRef(handler));
 }
 /**
 * Get a handler with the specified *name*, or None if there isn't one with
 * that name.
 */
 export function getHandlerByName(name: string): Handler|null {
    return HANDLERS[name] ?? null
 }
 /**
 * Return all known handler names as an immutable set
 */
 export function getHandlerNames(): Handlers { return Object.freeze(HANDLERS) }
 /**
 * Handler instances dispatch logging events to specific destinations.
 *
 * The base handler class. Acts as a placeholder which defines the Handler
 * interface. Handlers can optionally use Formatter instances to format
 * records as desired. By default, no formatter is specified; in this case,
 * the 'raw' message as determined by record.message is logged.
 */
 export class Handler extends Filterer {
    protected _scope: string|null = null;
    protected _formatter: Formatter|null = null;
    protected _level: number;
    protected _closed: boolean = false;
    /**
     * Initializes the instance - basically setting the formatter to None
     * and the filter list to empty
     */
    constructor(level?: LogLevel) {
        super();
        this._level = checkLevel(level ?? NOTSET);
        // Add the handler to the global HANDLER_LIST (for cleanup on shutdown)
        addHandlerRef(this);
    }
    get level(): number { return this._level }
    set level(level: LogLevel|string) { this._level = checkLevel(level) }
    get scope(): string|null { return this._scope }
    set scope(scope: string) { this._scope = scope }
    get closed(): boolean { return this._closed }
    /**
     * Format the specified record.
     *
     * If a formatter is set, use it. Otherwise, use the default formatter for
     * the module.
     */
    format(record: LogRecord): string {
        const fmt = this.formatter ?? DEFAULT_FORMATTER;
        return fmt.format(record);
    }
    /**
     * Do whatever it takes to actually log the specified logging record.
     *
     * This version is intended to be implemented by subclasses and so raises a
     * NotImplementedError.
     */
    emit(record: LogRecord) {
        throw new NotImplementedError(
            'emit must be implemented by Handler subclass'
        )
    }
    /**
     * Conditionally emit the specfied logging record.
     *
     * Emission depends on filters which may have been added to the handler.
     * Wrap the actual emission of the record with acquisition/release of the
     * I/O thread lock.
     */
     handle(record: LogRecord) {
        const rv = this.filter(record);
        if (!rv) { return }
        let filtered = record;
        if ((rv as any) instanceof LogRecord) {
            filtered = rv as unknown as LogRecord
        }
        this.emit(filtered)
    }
    /**
     * Tidy up any resources used by the handler
     *
     * This version removes the handler from an internal map of handlers, which
     * is used for handler lookup by scope. Subclasses should ensure that this
     * gets called from overriden close() methods.
     */
    close() {
        this._closed = true;
        if (this.scope && Object.keys(HANDLERS).includes(this.scope)) {
            delete HANDLERS[this.scope]
        }
    }
    /**
     * Handle errors which occur during an emit() call.
     *
     * This method should be called from handlers when an exception is
     * encountered during an emit() call.
     */
    handleError(record: LogRecord) {
        try {
            console.error('--- Logging error ---');
            console.error('Error in handler for record:', record.scope, record.msg);
        }
        catch (_) {
            // silently ignore errors in error handling
        }
    }
    get formatter(): Formatter|null { return this._formatter }
    set formatter(fmt: Formatter) { this._formatter = fmt }
 }
 /**
 * A handler class which writes logging records, appropriately formatted,
 * to a stream. Note that this class does not close the stream, as
 * the default stream may be shared.
 */
 export class StreamHandler extends Handler {
    protected stream: Writable;
    constructor(stream?: Writable) {
        super();
        this.stream = stream ?? DEFAULT_STREAM;
    }
    emit(record: LogRecord) {
        try {
            const msg = this.format(record);
            this.stream.write(msg);
        }
        catch (e) {
            this.handleError(record);
        }
    }
 }
 /**
 * A handler class which writes logging records to the browser console,
 * mapping log levels to the appropriate console method.
 *
 * This is the primary handler for browser environments.
 */
 export class ConsoleHandler extends Handler {
    emit(record: LogRecord) {
        try {
            const msg = this.format(record);
            if (record.levelno >= ERROR) {
                console.error(msg);
            }
            else if (record.levelno >= WARNING) {
                console.warn(msg);
            }
            else {
                console.log(msg);
            }
        }
        catch (e) {
            this.handleError(record);
        }
    }
 }
 export interface FileHandlerOptions {
    filename: string
    filemode?: string
    encoding?: string
    errors?: string
 }
 export class FileHandler extends StreamHandler {
    constructor(options: FileHandlerOptions) {
        super();
        throw new NotImplementedError(
            'FileHandler is not available in browser environments. ' +
            'Use ConsoleHandler or a storage-backed handler instead.'
        );
    }
 }
 /**
 * A handler that persists log records to browser localStorage.
 *
 * Records are stored as a JSON array of formatted strings under a
 * configurable key. Log rotation is supported by entry count and/or
 * byte size to avoid exceeding storage quotas.
 */
 export interface LocalStorageHandlerOptions {
    /**
     * localStorage key to store entries under.
     * Defaults to 'esm-logging'.
     */
    key?: string;
    /**
     * Maximum number of entries to retain. Oldest entries are discarded
     * first. Set to 0 for no entry limit. Defaults to 1000.
     */
    maxEntries?: number;
    /**
     * Maximum size in bytes (as measured by the JSON-serialized string
     * length). Oldest entries are discarded to stay within this limit.
     * Set to 0 for no byte limit. Defaults to 0.
     */
    maxBytes?: number;
 }
 export class LocalStorageHandler extends Handler {
    protected key: string;
    protected maxEntries: number;
    protected maxBytes: number;
    constructor(options?: LocalStorageHandlerOptions) {
        super();
        if (typeof localStorage === 'undefined') {
            throw new NotImplementedError(
                'LocalStorageHandler requires a browser environment with localStorage'
            );
        }
        this.key = options?.key ?? 'esm-logging';
        this.maxEntries = options?.maxEntries ?? 1000;
        this.maxBytes = options?.maxBytes ?? 0;
    }
    emit(record: LogRecord) {
        try {
            const msg = this.format(record);
            const entries = this.getEntries();
            entries.push(msg);
            this._rotate(entries);
            this._setEntries(entries);
        }
        catch (e) {
            this.handleError(record);
        }
    }
    /**
     * Retrieve all stored log entries.
     */
    getEntries(): string[] {
        try {
            const data = localStorage.getItem(this.key);
            return data ? JSON.parse(data) : [];
        }
        catch {
            return [];
        }
    }
    /**
     * Remove all stored log entries.
     */
    clearEntries() {
        localStorage.removeItem(this.key);
    }
    close() {
        super.close();
    }
    /**
     * Discard oldest entries to stay within maxEntries and maxBytes limits.
     */
    protected _rotate(entries: string[]) {
        if (this.maxEntries > 0) {
            while (entries.length > this.maxEntries) {
                entries.shift();
            }
        }
        if (this.maxBytes > 0) {
            while (entries.length > 0) {
                const serialized = JSON.stringify(entries);
                if (serialized.length <= this.maxBytes) { break }
                entries.shift();
            }
        }
    }
    protected _setEntries(entries: string[]) {
        localStorage.setItem(this.key, JSON.stringify(entries));
    }
 }
 /**
 * This class is like a StreamHandler using sys.stderr, but always uses
 * whatever sys.stderr is currently set to rather than the value of
 * sys.stderr at handler construction time.
 */
 export class StderrHandler extends Handler {
    constructor(level: LogLevel) { super(level) }
    emit(record: LogRecord) {
        try {
            const msg = this.format(record);
            console.error(msg);
        }
        catch (e) {
            this.handleError(record);
        }
    }
 }
--- a/src/helper/stream.ts
+++ b/src/helper/stream.ts
@ -1,2 +1,33 @@
 /**
 * Minimal writable stream interface for browser compatibility.
 *
 * This abstracts over Node.js streams and browser console output,
 * providing a common write target for handlers.
 */
 export interface Writable {
    write(data: string): void;
 }
-export type MillisecondsSinceUnixEpoch = number;
+/**
 * A Writable backed by console.log.
 */
 export class ConsoleWritable implements Writable {
    write(data: string): void {
        console.log(data);
    }
 }
 /**
 * A Writable backed by console.error (stderr equivalent).
 */
 export class StderrWritable implements Writable {
    write(data: string): void {
        console.error(data);
    }
 }
 /**
 * Default output stream. Uses console.error to match Python's default
 * of writing to sys.stderr.
 */
 export const DEFAULT_STREAM: Writable = new StderrWritable();
--- a/src/index.ts
+++ b/src/index.ts
--- a/src/log-level.ts
+++ b/src/log-level.ts
@ -0,0 +1,118 @@
 /*---------------------------------------------------------------------------
   Level related stuff
  ---------------------------------------------------------------------------
  Default levels and level names, these can be replaced with any positive set
  of values having corresponding names. There is a pseudo-level, NOTSET, which
  is only really there as a lower limit for user-defined levels. Handlers and
  loggers are initialized with NOTSET so that they will log all messages, even
  at user-defined levels.
 */
 export type LogLevel = number;
 /**
 * An indication that something unexpected happened, or that a problem might
 * occur in the near future (e.g. ‘disk space low’). The software is still
 * working as expected.
 */
 export const CRITICAL = 50;
 export const FATAL = CRITICAL;
 /**
 * Due to a more serious problem, the software has not been able to perform some
 * function.
 */
 export const ERROR = 40;
 /**
 * An indication that something unexpected happened, or that a problem might
 * occur in the near future (e.g. ‘disk space low’). The software is still
 * working as expected.
 */
 export const WARNING = 30;
 export const WARN = WARNING;
 /**
 * Confirmation that things are working as expected.
 */
 export const INFO = 20;
 /**
 * Detailed information, typically only of interest to a developer trying to
 * diagnose a problem.
 */
 export const DEBUG = 10;
 /**
 * When set on a logger, indicates that ancestor loggers are to be consulted to
 * determine the effective level. If that still resolves to NOTSET, then all
 * events are logged. When set on a handler, all events are handled.
 */
 export const NOTSET = 0;
 const LEVELTONAME: {[key: number]: string} = {
    [CRITICAL]: 'CRITICAL',
    [ERROR]: 'ERROR',
    [WARNING]: 'WARNING',
    [INFO]: 'INFO',
    [DEBUG]: 'DEBUG',
    [NOTSET]: 'NOTSET'
 }
 const NAMETOLEVEL: {[key: string]: number} = {
    CRITICAL: CRITICAL,
    ERROR: ERROR,
    WARNING: WARNING,
    INFO: INFO,
    DEBUG: DEBUG,
    NOTSET: NOTSET,
 }
 function getLevelNamesMapping() {
    return Object.assign({}, NAMETOLEVEL);
 }
 /**
 * Return the textual or numeric representation of logging level 'level'
 *
 * @param level
 */
 export function getLevelName(level: string|number): string|number {
    var result: string|number = LEVELTONAME[level as number];
    if (result !== undefined) { return result }
    result = NAMETOLEVEL[level as string];
    if (result !== undefined) { return result }
    return `Level ${level}`;
 }
 /**
 * Associate 'levelName' with 'level'
 *
 * @param level
 * @param levelName
 */
 export function addLevelName(level: number, levelName: string) {
    LEVELTONAME[level] = levelName;
    NAMETOLEVEL[levelName] = level;
 }
 export function checkLevel(level: number|string): number {
    var rv: number;
    if (typeof level == 'number') { rv = level }
    else if (typeof level == 'string') {
        if (!Object.keys(NAMETOLEVEL).includes(level as string)) {
            throw new Error(`Unknown level: ${level}`)
        }
        rv = NAMETOLEVEL[level]
    }
    else {
        throw new Error(`Level not a number or valid string: ${level}`)
    }
    return rv
 }
--- a/src/log-record.ts
+++ b/src/log-record.ts
@ -0,0 +1,96 @@
 import { getLevelName, LogLevel } from './log-level';
 import { MillisecondsSinceUnixEpoch } from './helper/datetime';
 //---------------------------------------------------------------------------
 // The logging record
 //---------------------------------------------------------------------------
 /**
 * options for instantiating a new log record
 */
 export interface LogRecordOptions {
    /**
     * The numeric level of the logging event (such as 10 for DEBUG, 20 for
     * INFO, etc). Note that this is converted to two attributes of the
     * LogRecord: levelno for the numeric value and levelname for the
     * corresponding level name.
     */
    level: number,
    file?: string,
    /**
     * The line number in the source file where the logging call was made.
     */
    lno?: number,
    /**
     * The event description message, which can be a %-format string with
     * placeholders for variable data, or an arbitrary object (see Using
     * arbitrary objects as messages).
     */
    msg: string,
    /**
     * Variable data to merge into the msg argument to obtain the event
     * description.
     */
    args?: any[],
 }
 export type LogRecordFactory = { (name: string, options: LogRecordOptions): LogRecord };
 /**
 * LogRecord instances are created every time something is logged. They contain
 * all the information pertinent to  the event being logged. The main
 * information parssed in is msg and args, which are combined using str(msg) %
 * args to create the message field of the record. The record also includes
 * information such as when the record was created, the source line where the
 * logging call was made, and any exception information to be logged.
 */
 export class LogRecord {
    public readonly levelno: LogLevel;
    public readonly levelname: string|LogLevel;
    public readonly scope: string;
    public readonly name: string;
    public readonly msg: string;
    public readonly args: any[]|undefined;
    public message: string = '';
    public readonly created: MillisecondsSinceUnixEpoch = Date.now();
    public asctime: string = '';
    constructor(scope: string, options: LogRecordOptions) {
        this.levelno = options.level;
        this.levelname = getLevelName(options.level);
        this.scope = scope;
        this.name = scope;
        this.msg = options.msg;
        this.args = options.args;
    }
    getMessage(): string {
        let msg = String(this.msg);
        if (this.args && this.args.length > 0) {
            msg = this.args.reduce(
                (s, arg) => s.replace('%s', String(arg)),
                msg
            );
        }
        return msg;
    }
 }
 export var logRecordFactory = (scope: string, options: LogRecordOptions) => {
    return new LogRecord(scope, options)
 };
 /**
 * Define which class use when instantiating log records.
 *
 * @param factory - A callable which will be called to instantiate a log record.
 *                  Pass a clojure, if your factory is a class already.
 */
 export function setLogRecordFactory(factory: LogRecordFactory) {
    logRecordFactory = factory
 }
 export function getLogRecordFactory(): LogRecordFactory {
    return logRecordFactory
 }
--- a/src/logger.ts
+++ b/src/logger.ts
@ -0,0 +1,363 @@
 import {
    LogLevel,
    DEBUG,
    INFO,
    WARNING,
    ERROR,
    CRITICAL,
    NOTSET,
    checkLevel,
 } from './log-level';
 import { 
    LogRecord,
    logRecordFactory,
    LogRecordOptions,
 } from './log-record';
 import { Handler, StderrHandler } from './handler';
 import {
    NotImplementedError,
    KeyError,
    ValueError,
    StackTrace,
 } from './helper/error';
 import { Manager } from './manager';
 import { Filterer } from './filter';
 //---------------------------------------------------------------------------
 // Logger classes and functions
 //---------------------------------------------------------------------------
 export type ExecutionInfo = [string, Error, StackTrace];
 export var throwErrors: boolean = true;
 export const DEFAULT_LAST_RESORT = new StderrHandler(WARNING);
 export var lastResort = DEFAULT_LAST_RESORT;
 export type LoggerClass = { new(): Logger };
 /**
 * context of a logging event/trigger
 */
 export interface LogOptions{
    /**
     * 
     */
    excInfo: ExecutionInfo|Error|null,
    /**
     * 
     */
    extra: {[key: string]: any}|null,
    /**
     *
     */
    stackInfo: boolean,
    /**
     *
     */
    stackLevel: number
 }
 const DEFAULT_LOG_OPTIONS: LogOptions = Object.freeze({
    excInfo: null,
    extra: null,
    stackInfo: false,
    stackLevel: 1
 });
 /**
 * Instances of the logger class represent a single logging channel. A 'logging
 * channel' indicates an area of an application. Exactly how an 'area' is
 * defined is up to the application developer. Since an application can have any
 * number of areas, logging channels are identified by a unique string.
 * Application areas can be nested (e.g. an area of input process might include
 * sub-areas "read CSV file", "read XLS files" and "read Gnumeric files"). To
 * cater for this natural nesting, channel ames are organized into a namespace
 * hierarchy where levels are separated by periods, much like the Java or Python
 * package namespace. So in the instance given above, channel names might be
 * "input" for the upper level, and "input.csv", "input.xls" and "input.gnu" for
 * the sub-levels.
 * There is no arbitrary limit to the depth of nesting.
 */
 export class Logger extends Filterer {
    public readonly scope: string;
    public _level: number;
    private  _manager: Manager|null = null;
    public readonly parent: Logger|null = null;
    public readonly propagate: boolean = true;
    public readonly handlers: Handler[] = [];
    public readonly disabled: boolean = false;
    private cache: {[key: number]: boolean} = {};
    /**
     * Initialize the logger with a name and an optional level
     *
     * @param scope - 
     * @param level -
     * @param manager -
     */
    constructor(
        scope: string,
        level?: LogLevel,
    ) {
        super();
        this.scope = scope;
        this._level = checkLevel(level ?? NOTSET);
    }
    public get level() { return this._level }
    public set level(level: LogLevel) { this._level = checkLevel(level) }
    public get manager(): Manager|null { return this._manager }
    public set manager(manager: Manager) {
        if (this._manager) {
            throw new ValueError('logger can only be assigned to manager once');
        }
        this._manager = manager;
    }
    public setLevel(level: LogLevel) {
        this.level = checkLevel(level);
        //this.manager.clearCache()
    }
    /**
     * Get the effective level for this logger.
     *
     * Loop through this logger and its parents in the logger hierarchy, looking
     * for a non-zero logging level. Return the first one found.
     */
    public getEffectiveLevel() {
        var logger: Logger|null = this;
        while (logger) {
            if (logger.level) { return logger.level }
            logger = logger.parent;
        }
        return NOTSET;
    }
    /**
     * Is this logger enabled for level 'level'?
     */
    public isEnabledFor(level: LogLevel): boolean {
        if (this.disabled) { return false }
        if (level in this.cache) {
            return this.cache[level];
        }
        if (this._manager && this._manager.disable >= level) {
            this.cache[level] = false;
            return false;
        }
        this.cache[level] = level >= this.getEffectiveLevel();
        return this.cache[level];
    }
    /**
     * Log 'msg % args' with severity 'DEBUG'
     *
     * To pass exception information, use the keyword argument exc_info with
     * a true value, e.g.
     *
     * ```
     * logger.debug("Houston, we have a thorny problem", { exc_info: true })
     * ```
     */
    public debug(msg: string, options?: LogOptions) {
        if (this.isEnabledFor(DEBUG)) { this._log(DEBUG, msg, options) }
    }
    /**
     * Log 'msg % args' with severity 'INFO'
     */
    public info(msg: string, options?: LogOptions) {
        if (this.isEnabledFor(INFO)) { this._log(INFO, msg, options) }
    }
    /**
     * Log 'msg % args' with severity 'WARNING'
     */
    public warning(msg: string, options?: LogOptions) {
        if (this.isEnabledFor(WARNING)) { this._log(WARNING, msg, options) }
    }
    /**
     * Log 'msg % args' with severity 'ERROR'
     */
    public error(msg: string, options?: LogOptions) {
        if (this.isEnabledFor(ERROR)) { this._log(ERROR, msg, options) }
    }
    /**
     * Log 'msg % args' with severity 'CRITICAL'
     */
    public critical(msg: string, options?: LogOptions) {
        if (this.isEnabledFor(CRITICAL)) { this._log(CRITICAL, msg, options) }
    }
    /**
     * A factory method which can be overriden in subclasses to create
     * specialized LogRecords.
     *
     * 
     */
    protected makeRecord(
        name: string,
        level: LogLevel,
        msg: string,
        options: LogOptions,
    ): LogRecord {
        var recordOptions: LogRecordOptions = {
            level: level,
            msg: msg,
        };
        var rv = logRecordFactory(name, recordOptions);
        if (options.extra !== null) {
            Object.entries(options.extra!).forEach((item) => {
                var [k, v] = item;
                if (['message', 'asctime'].includes(k) ||
                    Object.keys(rv).includes(k)) {
                    throw new KeyError(`attempt to overwrite ${k} in LogRecord`)
                }
                (rv as any)[k] = options.extra![k as string] as any
            })
        }
        return rv
    }
    /**
     * Low-level logging routine which creates a LogRecord and then calls the
     * handlers of this logger to handle the record.
     */
    protected _log(level: LogLevel, msg: string, options?: LogOptions) {
        options = options ?? DEFAULT_LOG_OPTIONS;
        options = { ...DEFAULT_LOG_OPTIONS, ...options };
        var sinfo=null;
        if (options!.excInfo !== null) {
            if (options!.excInfo instanceof Error) {
                var excInfo: ExecutionInfo = [
                    typeof options!.excInfo,
                    options!.excInfo,
                    options!.excInfo.stack!
                ]
            }
            else if (!(options!.excInfo instanceof Array)) {
                throw new NotImplementedError("would try to get the callee stack from the system. Probably will use stacktrace.js as this needs to be implemented browser-specific.");
            }
        }
        const record = this.makeRecord(this.scope, level, msg, options);
        this.handle(this.scope, record);
    }
    /**
     * Call the handlers for the specified record.
     *
     * This method is used for unpickled records received from a socket, as well
     * as those created locally. Logger-level filtering is applied.
     */
    protected handle(scope: string, record: LogRecord) {
        if (this.disabled) { return }
        var maybeRecord = this.filter(record);
        if (!maybeRecord) { return }
        if ((maybeRecord as any) instanceof LogRecord) { record = maybeRecord }
        this.callHandlers(record)
    }
    /**
     * Pass a record to all relevant handlers.
     *
     * Loop through all handlers for this logger and its parents n the logger
     * hierarchy. If no handler was found, output a one-off error message to
     * sys.stderr. Stop searching up the hierarchy whenever a logger with the
     * "propagate" attribute set to zero is found - that will be the last logger
     * whose handlers are called.
     */
    protected callHandlers(record: LogRecord) {
        var c: Logger|null = this;
        var found = 0;
        while (c) {
            for (var i = 0; i < c.handlers.length; i += 1) {
                let hdlr = c.handlers[i];
                found = found + 1;
                if (record.levelno >= hdlr.level) { hdlr.handle(record) }
            }
            if (!c.propagate) { c = null }
            else { c = c.parent }
        }
        if (found == 0) {
            if (lastResort) {
                if (record.levelno >= lastResort.level) {
                    lastResort.handle(record)
                }
                else if (throwErrors && (this.manager && !this.manager.emittedNoHandlerWarning)) {
                    console.error(
                        `No handlers could be found for logger ${this.scope}`
                    );
                    this.manager.emittedNoHandlerWarning = true;
                }
            }
        }
    }
    public clear() {
        for (var property in this.cache) delete this.cache[property];
    }
    /**
     * Remove the specified handler from this logger.
     */
    public addHandler(hdlr: Handler) {
        const i = this.handlers.indexOf(hdlr); 
        if (i === -1) { this.handlers.push(hdlr) }
    }
    /**
     * Remove the specified handler from this logger.
     */
    public removeHandler(hdlr: Handler) {
        const i = this.handlers.indexOf(hdlr); 
        if (i !== -1) { delete this.handlers[i] }
    }
 }
 /**
 * A root logger is not that different to any other logger, except that it must
 * have a logging level and there is only one instance of in a manager's
 * hierarchy.
 */
 export class RootLogger extends Logger {
    constructor(level: LogLevel) {
        super('root', level);
    }
 }
 /**
 * root logger (singleton)
 */
 export const ROOT = new RootLogger(WARNING);
--- a/src/manager.ts
+++ b/src/manager.ts
@ -0,0 +1,185 @@
 import { 
    Logger,
    LoggerClass,
    RootLogger,
    ROOT,
 } from './logger';
 import { LogRecordFactory } from './log-record';
 import {
    LogLevel,
    NOTSET,
    checkLevel,
 } from './log-level'
 //---------------------------------------------------------------------------
 // Manager classes and functions
 //---------------------------------------------------------------------------
 var loggerClass = Logger;
 /**
 * Placeholder instance
 */
 class Placeholder {
    public loggers: Logger[] = [];
    /**
     * initialize with the specified logger being a child of this placeholder.
     */
    constructor(logger: Logger) { this.push(logger) }
    /**
     * add the specified logger as a child of this placeholder
     */
    public push(logger: Logger) {
        if (!this.loggers.includes(logger)) { this.loggers.push(logger) }
    }
 }
 /**
 * There is [under normal circumstances] just one Manager intance, which holds
 * the hierarchy of loggers.
 */
 export class Manager {
    public readonly root: RootLogger;
    protected _disable: number = 0;
    public emittedNoHandlerWarning: boolean = false;
    protected loggers: {[key: string]: Logger} = {};
    protected _loggerClass: LoggerClass|null = null;
    protected _logRecordFactory: LogRecordFactory|null = null;
    public get disable(): number { return this._disable }
    public set disable(level: LogLevel) { this._disable = checkLevel(level) }
    /**
     * Initialize the manager with the root node of the logger hierarchy
     */
    constructor(root: RootLogger) {
        this.root = root;
    }
    /**
     * Get a logger with the specified name (scope name), creating it, if it
     * does not yet exist. This name is a dot-separated hierarchical name, such
     * as "a", "a.b", "a.b.c" or similar.
     *
     * If a PlaceHolder existed for the specified name [i.e. the logger didn't
     * exist but a child of it did], replace it with the created logger and fix
     * up the parent/child references which pointed to the placeholder to now
     * point to the logger.
     */
    getLogger(scope: string): Logger {
        let rv: Logger;
        if (scope in this.loggers) {
            const existing = this.loggers[scope];
            if (existing instanceof Placeholder) {
                rv = new (this._loggerClass ?? loggerClass)(scope, NOTSET);
                rv.manager = this;
                this.loggers[scope] = rv;
                this._fixupChildren(existing, rv);
                this._fixupParents(rv);
            }
            else {
                rv = existing;
            }
        }
        else {
            rv = new (this._loggerClass ?? loggerClass)(scope, NOTSET);
            rv.manager = this;
            this.loggers[scope] = rv;
            this._fixupParents(rv);
        }
        return rv;
    }
    /**
     * Ensure that there are either loggers or placeholders all the way from
     * the specified logger to the root of the logger hierarchy.
     */
    protected _fixupParents(logger: Logger) {
        const name = logger.scope;
        let i = name.lastIndexOf('.');
        let rv: Logger | null = null;
        while (i > 0 && !rv) {
            const substr = name.substring(0, i);
            if (!(substr in this.loggers)) {
                this.loggers[substr] = new Placeholder(logger) as unknown as Logger;
            }
            else {
                const obj = this.loggers[substr];
                if (obj instanceof Placeholder) {
                    obj.push(logger);
                }
                else {
                    rv = obj;
                }
            }
            i = name.lastIndexOf('.', i - 1);
        }
        (logger as unknown as { parent: Logger }).parent = rv ?? this.root;
    }
    /**
     * Ensure that children of the placeholder ph are connected to the
     * specified logger.
     */
    protected _fixupChildren(ph: Placeholder, logger: Logger) {
        const name = logger.scope;
        for (const c of ph.loggers) {
            if (c.parent!.scope.substring(0, name.length) !== name) {
                (logger as unknown as { parent: Logger }).parent = c.parent!;
                (c as unknown as { parent: Logger }).parent = logger;
            }
        }
    }
    /**
     * Set the class to be used when instantiating a logger with this Manager.
     */
    set loggerClass(class_: LoggerClass) {
        if (class_ !== Logger) {
            if (!(class_.prototype instanceof Logger)) {
                throw new TypeError("logger not derived from logging.Logger: ")
            }
        }
        this._loggerClass = class_;
    }
    /**
     * Set the factory to be used when instantiating a log record with this
     * Manager.
     */
    set logRecordFactory(factory: LogRecordFactory) {
        this._logRecordFactory = factory;
    }
    /**
     * clear the cache for all loggers in loggerDict
     */
    public clear() {
        Object.values(this.loggers).forEach((logger) => {
            if (!(logger instanceof Placeholder)) {
                logger.clear();
            }
        });
    }
 }
 /**
 * log manager (singleton)
 */
 export const MANAGER = new Manager(ROOT);
--- a/tests/test.ts
+++ b/tests/test.ts
@ -1,86 +0,0 @@
 import {expect, jest, test} from '@jest/globals';
 describe('Logger', () => {
    it('can be instantiated', () => {
        //const logger = new logging.Logger('test', 0);
    })
 });
 describe('getLevelName', () => {
    var logging: any;
    beforeEach(() => {
        // there are a couple of singletons, which I'm not yet sure if they need
        // to be reloaded for every test case
        logging = require('../src');
    });
    it('numeric to textual representation of built-ins', () => {
        expect(
            logging.getLevelName(logging.CRITICAL)
        ).toBe('CRITICAL');
        expect(
            logging.getLevelName(logging.FATAL)
        ).toBe('CRITICAL');
        expect(
            logging.getLevelName(logging.ERROR)
        ).toBe('ERROR');
        expect(
            logging.getLevelName(logging.WARNING)
        ).toBe('WARNING');
        expect(
            logging.getLevelName(logging.WARN)
        ).toBe('WARNING');
        expect(
            logging.getLevelName(logging.INFO)
        ).toBe('INFO');
        expect(
            logging.getLevelName(logging.DEBUG)
        ).toBe('DEBUG');
        expect(
            logging.getLevelName(logging.NOTSET)
        ).toBe('NOTSET');
    });
    it('textual to numeric representation of built-ins', () => {
        expect(
            logging.getLevelName('CRITICAL')
        ).toBe(logging.CRITICAL);
        expect(
            logging.getLevelName('FATAL')
        ).toBe(`Level FATAL`);
        expect(
            logging.getLevelName('ERROR')
        ).toBe(logging.ERROR);
        expect(
            logging.getLevelName('WARNING')
        ).toBe(logging.WARNING);
        expect(
            logging.getLevelName('WARN')
        ).toBe('Level WARN');
        expect(
            logging.getLevelName('INFO')
        ).toBe(logging.INFO);
        expect(
            logging.getLevelName('DEBUG')
        ).toBe(logging.DEBUG);
        expect(
            logging.getLevelName('NOTSET')
        ).toBe(logging.NOTSET);
    });
 });
 describe('addLevelName', () => {
    var logging: any;
    beforeEach(() => {
        logging = require('../src');
    });
    it('numeric to textual representation of built-ins', () => {
        logging.addLevelName(80, 'FOOBAR');
        expect(logging.getLevelName(80)).toBe('FOOBAR');
        expect(logging.getLevelName('FOOBAR')).toBe(80);
    })
 });
--- a/tests/unit/config.test.ts
+++ b/tests/unit/config.test.ts
@ -0,0 +1,93 @@
 import {expect, jest, test} from '@jest/globals';
 import { basicConfig } from '../../src/config';
 import { MANAGER } from '../../src/manager';
 import { Handler } from '../../src/handler';
 import { LogRecord } from '../../src/log-record';
 import { Formatter } from '../../src/formatter';
 import { DEBUG, WARNING, ERROR } from '../../src/log-level';
 describe('basicConfig', () => {
    beforeEach(() => {
        MANAGER.root.handlers.splice(0, MANAGER.root.handlers.length);
    });
    test('adds a handler to the root logger', () => {
        basicConfig({});
        expect(MANAGER.root.handlers.length).toBeGreaterThan(0);
    });
    test('sets root logger level', () => {
        basicConfig({ level: DEBUG });
        expect(MANAGER.root.level).toBe(DEBUG);
    });
    test('does nothing when handlers already exist and force is false', () => {
        basicConfig({ level: DEBUG });
        const handlerCount = MANAGER.root.handlers.length;
        basicConfig({ level: ERROR });
        expect(MANAGER.root.handlers.length).toBe(handlerCount);
        expect(MANAGER.root.level).toBe(DEBUG);
    });
    test('replaces handlers when force is true', () => {
        basicConfig({ level: DEBUG });
        basicConfig({ level: ERROR, force: true });
        expect(MANAGER.root.level).toBe(ERROR);
    });
    test('throws on invalid style', () => {
        expect(() => {
            basicConfig({ style: 'X' });
        }).toThrow('style must be one of');
    });
    test('throws when stream and filename both specified', () => {
        expect(() => {
            basicConfig({
                stream: process.stderr,
                filename: 'test.log',
            });
        }).toThrow('should not be specified together');
    });
    test('throws when handlers and stream both specified', () => {
        class TestHandler extends Handler {
            emit(record: LogRecord) {}
        }
        expect(() => {
            basicConfig({
                handlers: [new TestHandler()],
                stream: process.stderr,
            });
        }).toThrow('should not be specified together');
    });
    test('uses provided handlers', () => {
        class TestHandler extends Handler {
            emit(record: LogRecord) {}
        }
        const handler = new TestHandler();
        basicConfig({ handlers: [handler] });
        expect(MANAGER.root.handlers).toContain(handler);
    });
    test('assigns formatter to handlers without one', () => {
        class TestHandler extends Handler {
            emit(record: LogRecord) {}
        }
        const handler = new TestHandler();
        expect(handler.formatter).toBeNull();
        basicConfig({ handlers: [handler] });
        expect(handler.formatter).not.toBeNull();
    });
    test('preserves existing formatter on handlers', () => {
        class TestHandler extends Handler {
            emit(record: LogRecord) {}
        }
        const handler = new TestHandler();
        const fmt = new Formatter({ fmt: '%(message)s' });
        handler.formatter = fmt;
        basicConfig({ handlers: [handler] });
        expect(handler.formatter).toBe(fmt);
    });
 });
--- a/tests/unit/formatter.test.ts
+++ b/tests/unit/formatter.test.ts
@ -0,0 +1,143 @@
 import {expect, jest, test} from '@jest/globals';
 import { Formatter, DEFAULT_FORMATTER } from '../../src/formatter';
 import { LogRecord } from '../../src/log-record';
 import { DEBUG, WARNING, INFO } from '../../src/log-level';
 import { MyError } from '../../src/helper/error';
 function makeRecord(level: number, msg: string): LogRecord {
    return new LogRecord('test.module', { level, msg });
 }
 describe('Formatter', () => {
    describe('constructor', () => {
        test('uses default format when no options given', () => {
            const fmt = new Formatter();
            const record = makeRecord(WARNING, 'hello');
            const result = fmt.format(record);
            expect(result).toBe('hello');
        });
        test('accepts custom format string', () => {
            const fmt = new Formatter({ fmt: '%(levelname)s - %(message)s' });
            const record = makeRecord(DEBUG, 'debug msg');
            expect(fmt.format(record)).toBe('DEBUG - debug msg');
        });
        test('throws on invalid style', () => {
            expect(() => new Formatter({ style: '{' })).toThrow('style must be one of');
        });
    });
    describe('format', () => {
        test('substitutes %(name)s with logger scope', () => {
            const fmt = new Formatter({ fmt: '[%(name)s] %(message)s' });
            const record = makeRecord(INFO, 'test');
            expect(fmt.format(record)).toBe('[test.module] test');
        });
        test('substitutes %(levelno)d with numeric level', () => {
            const fmt = new Formatter({ fmt: '%(levelno)d: %(message)s' });
            const record = makeRecord(WARNING, 'warn');
            expect(fmt.format(record)).toBe('30: warn');
        });
        test('substitutes %(levelname)s with level name', () => {
            const fmt = new Formatter({ fmt: '%(levelname)s %(message)s' });
            const record = makeRecord(DEBUG, 'msg');
            expect(fmt.format(record)).toBe('DEBUG msg');
        });
        test('handles multiple placeholders', () => {
            const fmt = new Formatter({
                fmt: '%(levelname)s:%(name)s:%(levelno)d:%(message)s'
            });
            const record = makeRecord(WARNING, 'multi');
            expect(fmt.format(record)).toBe('WARNING:test.module:30:multi');
        });
        test('throws on unknown field', () => {
            const fmt = new Formatter({ fmt: '%(nonexistent)s' });
            const record = makeRecord(DEBUG, 'test');
            expect(() => fmt.format(record)).toThrow('formatting field not found');
        });
        test('populates asctime when format uses it', () => {
            const fmt = new Formatter({
                fmt: '%(asctime)s %(message)s'
            });
            const record = makeRecord(INFO, 'timed');
            const result = fmt.format(record);
            expect(result).toContain('timed');
            expect(record.asctime.length).toBeGreaterThan(0);
        });
        test('does not populate asctime when format does not use it', () => {
            const fmt = new Formatter({ fmt: '%(message)s' });
            const record = makeRecord(INFO, 'no time');
            fmt.format(record);
            expect(record.asctime).toBe('');
        });
    });
    describe('formatTime', () => {
        test('returns ISO8601-like string by default', () => {
            const fmt = new Formatter();
            const record = makeRecord(INFO, 'test');
            const result = fmt.formatTime(record);
            expect(result).toMatch(/^\d{4}-\d{2}-\d{2} \d{2}:\d{2}:\d{2}/);
        });
        test('uses custom datefmt with strftime tokens', () => {
            const fmt = new Formatter();
            const record = makeRecord(INFO, 'test');
            const result = fmt.formatTime(record, '%Y/%m/%d');
            expect(result).toMatch(/^\d{4}\/\d{2}\/\d{2}$/);
        });
    });
    describe('formatError', () => {
        test('returns stack trace when available', () => {
            const fmt = new Formatter();
            const err = new MyError('test error');
            const result = fmt.formatError(err);
            expect(result).toContain('test error');
            expect(result).toContain('\n');
        });
        test('returns string representation when no stack', () => {
            const fmt = new Formatter();
            const err = new MyError('no stack');
            err.stack = undefined;
            const result = fmt.formatError(err);
            expect(result).toContain('no stack');
        });
    });
    describe('usesTime', () => {
        test('returns true when format contains asctime', () => {
            const fmt = new Formatter({ fmt: '%(asctime)s %(message)s' });
            expect(fmt.usesTime()).toBe(true);
        });
        test('returns false when format does not contain asctime', () => {
            const fmt = new Formatter({ fmt: '%(message)s' });
            expect(fmt.usesTime()).toBe(false);
        });
    });
 });
 describe('LogRecord.getMessage', () => {
    test('returns the message string', () => {
        const record = makeRecord(INFO, 'plain message');
        expect(record.getMessage()).toBe('plain message');
    });
    test('substitutes %s args into message', () => {
        const record = new LogRecord('test', {
            level: INFO,
            msg: 'hello %s, you have %s items',
            args: ['world', '5'],
        });
        expect(record.getMessage()).toBe('hello world, you have 5 items');
    });
 });
--- a/tests/unit/handler.test.ts
+++ b/tests/unit/handler.test.ts
@ -0,0 +1,211 @@
 import {expect, jest, test} from '@jest/globals';
 import {
    Handler,
    StreamHandler,
    ConsoleHandler,
    StderrHandler,
    FileHandler,
 } from '../../src/handler';
 import { Formatter, DEFAULT_FORMATTER } from '../../src/formatter';
 import { LogRecord } from '../../src/log-record';
 import { Writable } from '../../src/helper/stream';
 import { DEBUG, INFO, WARNING, ERROR, CRITICAL, NOTSET } from '../../src/log-level';
 function makeRecord(level: number, msg: string): LogRecord {
    return new LogRecord('test', { level, msg });
 }
 describe('Handler', () => {
    describe('constructor', () => {
        test('defaults to NOTSET level', () => {
            const h = new Handler();
            expect(h.level).toBe(NOTSET);
        });
        test('accepts a level argument', () => {
            const h = new Handler(WARNING);
            expect(h.level).toBe(WARNING);
        });
    });
    describe('level setter', () => {
        test('sets the level without infinite recursion', () => {
            const h = new Handler();
            h.level = ERROR;
            expect(h.level).toBe(ERROR);
        });
    });
    describe('formatter', () => {
        test('getter returns null when no formatter set', () => {
            const h = new Handler();
            expect(h.formatter).toBeNull();
        });
        test('getter returns assigned formatter', () => {
            const h = new Handler();
            const fmt = new Formatter();
            h.formatter = fmt;
            expect(h.formatter).toBe(fmt);
        });
    });
    describe('format', () => {
        test('uses DEFAULT_FORMATTER when no formatter assigned', () => {
            const h = new Handler();
            const record = makeRecord(DEBUG, 'hello');
            const result = h.format(record);
            expect(typeof result).toBe('string');
        });
        test('returns a string', () => {
            const h = new Handler();
            const record = makeRecord(WARNING, 'test message');
            expect(typeof h.format(record)).toBe('string');
        });
    });
    describe('emit', () => {
        test('throws NotImplementedError on base class', () => {
            const h = new Handler();
            const record = makeRecord(DEBUG, 'hello');
            expect(() => h.emit(record)).toThrow('emit must be implemented');
        });
    });
    describe('close', () => {
        test('sets closed to true', () => {
            const h = new Handler();
            expect(h.closed).toBe(false);
            h.close();
            expect(h.closed).toBe(true);
        });
    });
    describe('handleError', () => {
        test('does not throw', () => {
            const h = new Handler();
            const record = makeRecord(DEBUG, 'test');
            expect(() => h.handleError(record)).not.toThrow();
        });
    });
 });
 describe('StreamHandler', () => {
    test('writes formatted output to the stream', () => {
        const written: string[] = [];
        const stream: Writable = { write: (data: string) => { written.push(data) } };
        const h = new StreamHandler(stream);
        const record = makeRecord(WARNING, 'stream test');
        h.emit(record);
        expect(written.length).toBe(1);
        expect(written[0]).toContain('stream test');
    });
    test('uses default stream when none provided', () => {
        const h = new StreamHandler();
        const record = makeRecord(DEBUG, 'default stream');
        expect(() => h.emit(record)).not.toThrow();
    });
    test('calls handleError on emit failure', () => {
        const stream: Writable = {
            write: () => { throw new Error('write failed') }
        };
        const h = new StreamHandler(stream);
        const record = makeRecord(DEBUG, 'fail');
        expect(() => h.emit(record)).not.toThrow();
    });
 });
 describe('ConsoleHandler', () => {
    let origLog: typeof console.log;
    let origWarn: typeof console.warn;
    let origError: typeof console.error;
    let logged: string[];
    let warned: string[];
    let errored: string[];
    beforeEach(() => {
        logged = [];
        warned = [];
        errored = [];
        origLog = console.log;
        origWarn = console.warn;
        origError = console.error;
        console.log = (...args: any[]) => { logged.push(args.join(' ')) };
        console.warn = (...args: any[]) => { warned.push(args.join(' ')) };
        console.error = (...args: any[]) => { errored.push(args.join(' ')) };
    });
    afterEach(() => {
        console.log = origLog;
        console.warn = origWarn;
        console.error = origError;
    });
    test('uses console.error for ERROR level', () => {
        const h = new ConsoleHandler();
        h.emit(makeRecord(ERROR, 'error msg'));
        expect(errored.length).toBe(1);
        expect(errored[0]).toContain('error msg');
    });
    test('uses console.error for CRITICAL level', () => {
        const h = new ConsoleHandler();
        h.emit(makeRecord(CRITICAL, 'critical msg'));
        expect(errored.length).toBe(1);
        expect(errored[0]).toContain('critical msg');
    });
    test('uses console.warn for WARNING level', () => {
        const h = new ConsoleHandler();
        h.emit(makeRecord(WARNING, 'warn msg'));
        expect(warned.length).toBe(1);
        expect(warned[0]).toContain('warn msg');
    });
    test('uses console.log for INFO level', () => {
        const h = new ConsoleHandler();
        h.emit(makeRecord(INFO, 'info msg'));
        expect(logged.length).toBe(1);
        expect(logged[0]).toContain('info msg');
    });
    test('uses console.log for DEBUG level', () => {
        const h = new ConsoleHandler();
        h.emit(makeRecord(DEBUG, 'debug msg'));
        expect(logged.length).toBe(1);
        expect(logged[0]).toContain('debug msg');
    });
 });
 describe('StderrHandler', () => {
    test('accepts a level', () => {
        const h = new StderrHandler(ERROR);
        expect(h.level).toBe(ERROR);
    });
    test('emits via console.error', () => {
        const errored: string[] = [];
        const origError = console.error;
        console.error = (...args: any[]) => { errored.push(args.join(' ')) };
        try {
            const h = new StderrHandler(DEBUG);
            h.emit(makeRecord(WARNING, 'stderr test'));
            expect(errored.length).toBe(1);
            expect(errored[0]).toContain('stderr test');
        }
        finally {
            console.error = origError;
        }
    });
 });
 describe('FileHandler', () => {
    test('throws NotImplementedError on construction', () => {
        expect(() => new FileHandler({
            filename: 'test.log'
        })).toThrow('not available in browser');
    });
 });
--- a/tests/unit/local-storage-handler.test.ts
+++ b/tests/unit/local-storage-handler.test.ts
@ -0,0 +1,158 @@
 import {expect, jest, test, beforeEach, afterEach} from '@jest/globals';
 import { LocalStorageHandler } from '../../src/handler';
 import { LogRecord } from '../../src/log-record';
 import { DEBUG, WARNING, ERROR } from '../../src/log-level';
 // mock localStorage for Node/Jest environment
 const store: {[key: string]: string} = {};
 const localStorageMock = {
    getItem: (key: string): string | null => store[key] ?? null,
    setItem: (key: string, value: string) => { store[key] = value },
    removeItem: (key: string) => { delete store[key] },
 };
 function clearStore() {
    for (const key of Object.keys(store)) { delete store[key] }
 }
 function makeRecord(level: number, msg: string): LogRecord {
    return new LogRecord('test', { level, msg });
 }
 beforeEach(() => {
    clearStore();
    (globalThis as any).localStorage = localStorageMock;
 });
 afterEach(() => {
    clearStore();
    delete (globalThis as any).localStorage;
 });
 describe('LocalStorageHandler', () => {
    describe('constructor', () => {
        test('uses default key and limits', () => {
            const h = new LocalStorageHandler();
            expect(h.getEntries()).toEqual([]);
        });
        test('throws when localStorage is unavailable', () => {
            delete (globalThis as any).localStorage;
            expect(() => new LocalStorageHandler()).toThrow(
                'requires a browser environment'
            );
        });
        test('accepts custom options', () => {
            const h = new LocalStorageHandler({
                key: 'custom-log',
                maxEntries: 50,
                maxBytes: 4096,
            });
            h.emit(makeRecord(DEBUG, 'test'));
            expect(store['custom-log']).toBeDefined();
            expect(store['esm-logging']).toBeUndefined();
        });
    });
    describe('emit', () => {
        test('stores formatted log entry', () => {
            const h = new LocalStorageHandler();
            h.emit(makeRecord(WARNING, 'hello'));
            const entries = h.getEntries();
            expect(entries.length).toBe(1);
            expect(entries[0]).toContain('hello');
        });
        test('appends multiple entries', () => {
            const h = new LocalStorageHandler();
            h.emit(makeRecord(DEBUG, 'first'));
            h.emit(makeRecord(DEBUG, 'second'));
            h.emit(makeRecord(DEBUG, 'third'));
            expect(h.getEntries().length).toBe(3);
        });
        test('persists across handler instances with same key', () => {
            const h1 = new LocalStorageHandler({ key: 'shared' });
            h1.emit(makeRecord(DEBUG, 'from h1'));
            const h2 = new LocalStorageHandler({ key: 'shared' });
            const entries = h2.getEntries();
            expect(entries.length).toBe(1);
            expect(entries[0]).toContain('from h1');
        });
    });
    describe('rotation by entry count', () => {
        test('discards oldest entries when maxEntries exceeded', () => {
            const h = new LocalStorageHandler({ maxEntries: 3 });
            h.emit(makeRecord(DEBUG, 'msg-1'));
            h.emit(makeRecord(DEBUG, 'msg-2'));
            h.emit(makeRecord(DEBUG, 'msg-3'));
            h.emit(makeRecord(DEBUG, 'msg-4'));
            const entries = h.getEntries();
            expect(entries.length).toBe(3);
            expect(entries[0]).toContain('msg-2');
            expect(entries[2]).toContain('msg-4');
        });
        test('maxEntries of 1 keeps only the latest', () => {
            const h = new LocalStorageHandler({ maxEntries: 1 });
            h.emit(makeRecord(DEBUG, 'old'));
            h.emit(makeRecord(DEBUG, 'new'));
            const entries = h.getEntries();
            expect(entries.length).toBe(1);
            expect(entries[0]).toContain('new');
        });
    });
    describe('rotation by byte size', () => {
        test('discards oldest entries when maxBytes exceeded', () => {
            const h = new LocalStorageHandler({ maxEntries: 0, maxBytes: 100 });
            // emit entries until we exceed the limit
            for (let i = 0; i < 20; i++) {
                h.emit(makeRecord(DEBUG, `message-${i}`));
            }
            const entries = h.getEntries();
            const serialized = JSON.stringify(entries);
            expect(serialized.length).toBeLessThanOrEqual(100);
            expect(entries.length).toBeGreaterThan(0);
        });
    });
    describe('getEntries', () => {
        test('returns empty array when no entries', () => {
            const h = new LocalStorageHandler();
            expect(h.getEntries()).toEqual([]);
        });
        test('returns empty array on corrupt data', () => {
            store['esm-logging'] = 'not valid json{{{';
            const h = new LocalStorageHandler();
            expect(h.getEntries()).toEqual([]);
        });
    });
    describe('clearEntries', () => {
        test('removes all stored entries', () => {
            const h = new LocalStorageHandler();
            h.emit(makeRecord(DEBUG, 'to be cleared'));
            expect(h.getEntries().length).toBe(1);
            h.clearEntries();
            expect(h.getEntries()).toEqual([]);
        });
    });
    describe('close', () => {
        test('sets closed to true', () => {
            const h = new LocalStorageHandler();
            expect(h.closed).toBe(false);
            h.close();
            expect(h.closed).toBe(true);
        });
    });
 });
--- a/tests/unit/log-level.test.ts
+++ b/tests/unit/log-level.test.ts
@ -0,0 +1,73 @@
 import {expect, jest, test} from '@jest/globals';
 import * as log_level from '../../src/log-level';
 describe('Logger', () => {
    it('can be instantiated', () => {
        //const logger = new log_level.Logger('test', 0);
    })
 });
 describe('getLevelName', () => {
    it('numeric to textual representation of built-ins', () => {
        expect(
            log_level.getLevelName(log_level.CRITICAL)
        ).toBe('CRITICAL');
        expect(
            log_level.getLevelName(log_level.FATAL)
        ).toBe('CRITICAL');
        expect(
            log_level.getLevelName(log_level.ERROR)
        ).toBe('ERROR');
        expect(
            log_level.getLevelName(log_level.WARNING)
        ).toBe('WARNING');
        expect(
            log_level.getLevelName(log_level.WARN)
        ).toBe('WARNING');
        expect(
            log_level.getLevelName(log_level.INFO)
        ).toBe('INFO');
        expect(
            log_level.getLevelName(log_level.DEBUG)
        ).toBe('DEBUG');
        expect(
            log_level.getLevelName(log_level.NOTSET)
        ).toBe('NOTSET');
    });
    it('textual to numeric representation of built-ins', () => {
        expect(
            log_level.getLevelName('CRITICAL')
        ).toBe(log_level.CRITICAL);
        expect(
            log_level.getLevelName('FATAL')
        ).toBe(`Level FATAL`);
        expect(
            log_level.getLevelName('ERROR')
        ).toBe(log_level.ERROR);
        expect(
            log_level.getLevelName('WARNING')
        ).toBe(log_level.WARNING);
        expect(
            log_level.getLevelName('WARN')
        ).toBe('Level WARN');
        expect(
            log_level.getLevelName('INFO')
        ).toBe(log_level.INFO);
        expect(
            log_level.getLevelName('DEBUG')
        ).toBe(log_level.DEBUG);
        expect(
            log_level.getLevelName('NOTSET')
        ).toBe(log_level.NOTSET);
    });
 });
 describe('addLevelName', () => {
    it('numeric to textual representation of built-ins', () => {
        log_level.addLevelName(80, 'FOOBAR');
        expect(log_level.getLevelName(80)).toBe('FOOBAR');
        expect(log_level.getLevelName('FOOBAR')).toBe(80);
    })
 });
--- a/tests/unit/logger.test.ts
+++ b/tests/unit/logger.test.ts
@ -0,0 +1,209 @@
 import {expect, jest, test} from '@jest/globals';
 import { Logger, RootLogger, ROOT } from '../../src/logger';
 import { Handler } from '../../src/handler';
 import { LogRecord } from '../../src/log-record';
 import { Formatter } from '../../src/formatter';
 import { Manager } from '../../src/manager';
 import {
    DEBUG,
    INFO,
    WARNING,
    ERROR,
    CRITICAL,
    NOTSET,
 } from '../../src/log-level';
 import { MyError } from '../../src/helper/error';
 describe('Logger', () => {
    describe('constructor', () => {
        test('sets scope and default level', () => {
            const logger = new Logger('test');
            expect(logger.scope).toBe('test');
            expect(logger.level).toBe(NOTSET);
        });
        test('accepts explicit level', () => {
            const logger = new Logger('test', WARNING);
            expect(logger.level).toBe(WARNING);
        });
    });
    describe('setLevel', () => {
        test('changes the level', () => {
            const logger = new Logger('test');
            logger.setLevel(ERROR);
            expect(logger.level).toBe(ERROR);
        });
    });
    describe('getEffectiveLevel', () => {
        test('returns own level when set', () => {
            const logger = new Logger('test', WARNING);
            expect(logger.getEffectiveLevel()).toBe(WARNING);
        });
        test('returns NOTSET when no level set and no parent', () => {
            const logger = new Logger('test');
            expect(logger.getEffectiveLevel()).toBe(NOTSET);
        });
    });
    describe('isEnabledFor', () => {
        test('returns true when level meets effective level', () => {
            const logger = new Logger('test', DEBUG);
            expect(logger.isEnabledFor(WARNING)).toBe(true);
            expect(logger.isEnabledFor(DEBUG)).toBe(true);
        });
        test('returns false when level is below effective level', () => {
            const logger = new Logger('test', WARNING);
            expect(logger.isEnabledFor(DEBUG)).toBe(false);
            expect(logger.isEnabledFor(INFO)).toBe(false);
        });
        test('caches results for repeated calls', () => {
            const logger = new Logger('test', WARNING);
            const first = logger.isEnabledFor(DEBUG);
            const second = logger.isEnabledFor(DEBUG);
            expect(first).toBe(second);
        });
        test('respects manager disable level', () => {
            const root = new RootLogger(WARNING);
            const manager = new Manager(root);
            const logger = manager.getLogger('test');
            logger.setLevel(DEBUG);
            logger.manager = manager;
            manager.disable = ERROR;
            logger.clear();
            expect(logger.isEnabledFor(DEBUG)).toBe(false);
            expect(logger.isEnabledFor(WARNING)).toBe(false);
            expect(logger.isEnabledFor(CRITICAL)).toBe(true);
        });
    });
    describe('manager property', () => {
        test('starts as null', () => {
            const logger = new Logger('test');
            expect(logger.manager).toBeNull();
        });
        test('can be assigned once', () => {
            const logger = new Logger('test');
            const root = new RootLogger(WARNING);
            const manager = new Manager(root);
            logger.manager = manager;
            expect(logger.manager).toBe(manager);
        });
        test('throws on second assignment', () => {
            const logger = new Logger('test');
            const root = new RootLogger(WARNING);
            const manager = new Manager(root);
            logger.manager = manager;
            expect(() => { logger.manager = manager }).toThrow('logger can only be assigned to manager once');
        });
    });
    describe('addHandler / removeHandler', () => {
        test('adds and removes handlers', () => {
            const logger = new Logger('test');
            const handler = new Handler(DEBUG);
            expect(logger.handlers.length).toBe(0);
            logger.addHandler(handler);
            expect(logger.handlers.length).toBe(1);
            logger.removeHandler(handler);
        });
        test('does not add duplicate handlers', () => {
            const logger = new Logger('test');
            const handler = new Handler(DEBUG);
            logger.addHandler(handler);
            logger.addHandler(handler);
            expect(logger.handlers.length).toBe(1);
        });
    });
    describe('level methods', () => {
        let logger: Logger;
        let emitted: LogRecord[];
        class TestHandler extends Handler {
            emit(record: LogRecord) { emitted.push(record) }
        }
        beforeEach(() => {
            logger = new Logger('test', DEBUG);
            emitted = [];
            logger.addHandler(new TestHandler(DEBUG));
        });
        test('debug emits at DEBUG level', () => {
            logger.debug('msg');
            expect(emitted.length).toBe(1);
            expect(emitted[0].levelno).toBe(DEBUG);
        });
        test('info emits at INFO level', () => {
            logger.info('msg');
            expect(emitted.length).toBe(1);
            expect(emitted[0].levelno).toBe(INFO);
        });
        test('warning emits at WARNING level', () => {
            logger.warning('msg');
            expect(emitted.length).toBe(1);
            expect(emitted[0].levelno).toBe(WARNING);
        });
        test('error emits at ERROR level', () => {
            logger.error('msg');
            expect(emitted.length).toBe(1);
            expect(emitted[0].levelno).toBe(ERROR);
        });
        test('critical emits at CRITICAL level', () => {
            logger.critical('msg');
            expect(emitted.length).toBe(1);
            expect(emitted[0].levelno).toBe(CRITICAL);
        });
        test('level methods respect effective level', () => {
            logger.setLevel(ERROR);
            logger.clear();
            logger.debug('no');
            logger.info('no');
            logger.warning('no');
            expect(emitted.length).toBe(0);
            logger.error('yes');
            logger.critical('yes');
            expect(emitted.length).toBe(2);
        });
    });
    describe('makeRecord', () => {
        test('throws KeyError when extra overwrites existing LogRecord key', () => {
            const logger = new Logger('test', DEBUG);
            expect(() => {
                logger.debug('test', {
                    excInfo: null,
                    extra: { scope: 'override' },
                    stackInfo: false,
                    stackLevel: 1,
                });
            }).toThrow('attempt to overwrite scope in LogRecord');
        });
    });
 });
 describe('RootLogger', () => {
    test('has scope "root"', () => {
        const root = new RootLogger(WARNING);
        expect(root.scope).toBe('root');
    });
    test('accepts a level', () => {
        const root = new RootLogger(ERROR);
        expect(root.level).toBe(ERROR);
    });
 });
--- a/tests/unit/manager.test.ts
+++ b/tests/unit/manager.test.ts
@ -0,0 +1,209 @@
 import {expect, jest, test} from '@jest/globals';
 import { Manager } from '../../src/manager';
 import { Logger, RootLogger } from '../../src/logger';
 import { Handler } from '../../src/handler';
 import { LogRecord } from '../../src/log-record';
 import { WARNING, DEBUG, INFO, NOTSET } from '../../src/log-level';
 function makeManager(): Manager {
    return new Manager(new RootLogger(WARNING));
 }
 describe('Manager', () => {
    describe('constructor', () => {
        test('stores the root logger', () => {
            const root = new RootLogger(WARNING);
            const manager = new Manager(root);
            expect(manager.root).toBe(root);
        });
    });
    describe('getLogger', () => {
        test('returns a Logger instance', () => {
            const manager = makeManager();
            const logger = manager.getLogger('app');
            expect(logger).toBeInstanceOf(Logger);
            expect(logger.scope).toBe('app');
        });
        test('returns the same logger for the same scope', () => {
            const manager = makeManager();
            const a = manager.getLogger('app');
            const b = manager.getLogger('app');
            expect(a).toBe(b);
        });
        test('returns different loggers for different scopes', () => {
            const manager = makeManager();
            const a = manager.getLogger('app');
            const b = manager.getLogger('lib');
            expect(a).not.toBe(b);
        });
        test('sets parent to root for top-level loggers', () => {
            const manager = makeManager();
            const logger = manager.getLogger('app');
            expect(logger.parent).toBe(manager.root);
        });
        test('sets parent to existing parent logger', () => {
            const manager = makeManager();
            const parent = manager.getLogger('app');
            const child = manager.getLogger('app.module');
            expect(child.parent).toBe(parent);
        });
        test('establishes hierarchy for deeply nested loggers', () => {
            const manager = makeManager();
            const top = manager.getLogger('a');
            const mid = manager.getLogger('a.b');
            const leaf = manager.getLogger('a.b.c');
            expect(leaf.parent).toBe(mid);
            expect(mid.parent).toBe(top);
            expect(top.parent).toBe(manager.root);
        });
        test('creates placeholders for intermediate loggers', () => {
            const manager = makeManager();
            const leaf = manager.getLogger('a.b.c');
            expect(leaf.parent).toBe(manager.root);
            const mid = manager.getLogger('a.b');
            expect(leaf.parent).toBe(mid);
            expect(mid.parent).toBe(manager.root);
        });
        test('fixes up children when intermediate logger is created', () => {
            const manager = makeManager();
            const leaf = manager.getLogger('a.b.c');
            const top = manager.getLogger('a');
            expect(top.parent).toBe(manager.root);
            const mid = manager.getLogger('a.b');
            expect(leaf.parent).toBe(mid);
        });
    });
    describe('disable', () => {
        test('defaults to 0', () => {
            const manager = makeManager();
            expect(manager.disable).toBe(0);
        });
        test('can be set to a level', () => {
            const manager = makeManager();
            manager.disable = WARNING;
            expect(manager.disable).toBe(WARNING);
        });
    });
    describe('loggerClass', () => {
        test('accepts Logger subclass', () => {
            const manager = makeManager();
            class CustomLogger extends Logger {}
            expect(() => { manager.loggerClass = CustomLogger as any }).not.toThrow();
        });
        test('rejects non-Logger class', () => {
            const manager = makeManager();
            class NotALogger {}
            expect(() => {
                manager.loggerClass = NotALogger as any;
            }).toThrow(TypeError);
        });
        test('accepts Logger itself', () => {
            const manager = makeManager();
            expect(() => { manager.loggerClass = Logger as any }).not.toThrow();
        });
    });
    describe('getLogger - manager assignment', () => {
        test('sets manager on newly created loggers', () => {
            const manager = makeManager();
            const logger = manager.getLogger('app');
            expect(logger.manager).toBe(manager);
        });
        test('sets manager on loggers created from placeholders', () => {
            const manager = makeManager();
            manager.getLogger('a.b.c');
            const mid = manager.getLogger('a.b');
            expect(mid.manager).toBe(manager);
        });
        test('isEnabledFor respects manager.disable via getLogger', () => {
            const manager = makeManager();
            const logger = manager.getLogger('app');
            logger.setLevel(DEBUG);
            expect(logger.isEnabledFor(DEBUG)).toBe(true);
            manager.disable = WARNING;
            logger.clear();
            expect(logger.isEnabledFor(DEBUG)).toBe(false);
            expect(logger.isEnabledFor(WARNING)).toBe(false);
        });
    });
    describe('propagation through hierarchy', () => {
        test('child logger propagates records to parent handler', () => {
            const manager = makeManager();
            const parent = manager.getLogger('app');
            const child = manager.getLogger('app.module');
            parent.setLevel(DEBUG);
            child.setLevel(DEBUG);
            const emitted: string[] = [];
            const handler = new (class extends Handler {
                emit(record: LogRecord) {
                    emitted.push(record.msg);
                }
            })(DEBUG);
            parent.addHandler(handler);
            child.info('propagated message');
            expect(emitted).toContain('propagated message');
        });
        test('child does not propagate to unrelated logger', () => {
            const manager = makeManager();
            const unrelated = manager.getLogger('other');
            const child = manager.getLogger('app.module');
            unrelated.setLevel(DEBUG);
            child.setLevel(DEBUG);
            const emitted: string[] = [];
            const handler = new (class extends Handler {
                emit(record: LogRecord) {
                    emitted.push(record.msg);
                }
            })(DEBUG);
            unrelated.addHandler(handler);
            child.info('should not reach');
            expect(emitted).not.toContain('should not reach');
        });
    });
    describe('clear', () => {
        test('clears logger caches', () => {
            const manager = makeManager();
            const logger = manager.getLogger('test');
            logger.isEnabledFor(DEBUG);
            manager.clear();
        });
        test('does not throw when placeholders exist', () => {
            const manager = makeManager();
            manager.getLogger('a.b.c');
            expect(() => manager.clear()).not.toThrow();
        });
    });
 });
--- a/vendor/tiara-gitflow-spec
+++ b/vendor/tiara-gitflow-spec
@ -0,0 +1 @@
 Subproject commit ee93479edce1da28f4abf68a362427f8d3134f80
Author	SHA1	Message	Date
Tiara Rodney	34be2f8395	Merge branch 'feature/13' into dev	2026-03-14 05:02:56 +01:00
Tiara Rodney	5b29c67d0d	todo(13): done	2026-03-14 05:02:55 +01:00
Tiara Rodney	37fd6194c7	test(handler): add tests for LocalStorageHandler	2026-03-14 04:57:32 +01:00
Tiara Rodney	6fd8c22ceb	feat(handler): implement LocalStorageHandler with rotation	2026-03-14 04:55:37 +01:00
Tiara Rodney	7479931714	todo(13): in-progress	2026-03-14 04:39:24 +01:00
Tiara Rodney	768ff9263d	Merge branch 'feature/10' into dev	2026-03-14 04:34:13 +01:00
Tiara Rodney	b254922d3c	todo(10): done	2026-03-14 04:34:08 +01:00
Tiara Rodney	1a74f2afa4	docs: add user guide, cookbook, and rewrite README	2026-03-14 04:33:53 +01:00
Tiara Rodney	741b959820	todo(10): in-progress	2026-03-14 02:34:31 +01:00
Tiara Rodney	e50fccff8f	Merge branch 'feature/9' into dev	2026-03-14 02:32:40 +01:00
Tiara Rodney	743e8ffc3b	todo(9): done	2026-03-14 02:32:35 +01:00
Tiara Rodney	5022a1e0bc	test(manager): add tests for manager assignment and propagation	2026-03-14 02:32:20 +01:00
Tiara Rodney	94c7d4a1da	feat(manager): set manager on created loggers, fix clear for placeholders getLogger() now assigns manager on newly created loggers so isEnabledFor can check manager.disable. When replacing a Placeholder, _fixupParents is also called to establish the parent chain. clear() skips Placeholder entries that lack a clear method.	2026-03-14 00:23:09 +01:00
Tiara Rodney	cfda9902f7	todo(9): in-progress Set manager on loggers created by getLogger(), verify propagation works end-to-end through the hierarchy.	2026-03-14 00:11:36 +01:00
Tiara Rodney	1d5ded82ba	Merge branch 'feature/8' into dev	2026-03-14 00:00:50 +01:00
Tiara Rodney	672b692013	todo(8): done Added browser-compatible Writable interface with ConsoleWritable and StderrWritable implementations. StreamHandler.emit() writes to a Writable stream. ConsoleHandler maps levels to console.warn/error/log. StderrHandler emits via console.error. FileHandler throws on construction in browser. Handler.handleError() logs diagnostics. Writable interface designed for extensibility (issue 13).	2026-03-14 00:00:50 +01:00
Tiara Rodney	216d2b5892	test(handler): add tests for StreamHandler, ConsoleHandler, StderrHandler Cover StreamHandler emit to custom Writable, default stream fallback, and error handling on write failure. Cover ConsoleHandler level-to- method mapping (error/warn/log). Cover StderrHandler console.error output. Cover FileHandler browser rejection. Cover Handler base class handleError not throwing.	2026-03-14 00:00:34 +01:00
Tiara Rodney	3a6332a855	feat(handler): implement StreamHandler, ConsoleHandler, StderrHandler emit StreamHandler.emit() writes formatted output to a Writable stream. ConsoleHandler maps log levels to console.warn/error/log. StderrHandler emits via console.error. handleError() logs diagnostics instead of throwing. FileHandler throws NotImplementedError on construction. Removed Node.js stream import and conditional require() block.	2026-03-13 23:57:37 +01:00
Tiara Rodney	e6b7f02166	feat(helper/stream): add browser-compatible Writable interface Define Writable interface, ConsoleWritable (console.log), and StderrWritable (console.error) as browser-safe stream abstractions. Export DEFAULT_STREAM backed by StderrWritable to match Python's sys.stderr default.	2026-03-13 23:29:09 +01:00
Tiara Rodney	c297bb4499	todo(8): in-progress Implement StreamHandler.emit(), ConsoleHandler for browser console API, and a browser-compatible stream abstraction. Design handler base with issue 13 (localStorage handler) in mind.	2026-03-13 23:27:50 +01:00
Tiara Rodney	1cab520ba1	Merge branch 'feature/7' into dev	2026-03-13 23:26:40 +01:00
Tiara Rodney	67803747c4	todo(7): done Implemented %-style field substitution in PercentFormatterStyle, JS Date-based formatTime with strftime token support and ISO8601 fallback, Error.stack-based formatError, and LogRecord.getMessage. Added message, name, msg, args fields to LogRecord.	2026-03-13 23:26:39 +01:00
Tiara Rodney	3422cfb799	test(formatter): add tests for formatting, formatTime, formatError Cover %-style substitution with %(name)s, %(levelno)d, %(levelname)s, multiple placeholders, unknown field errors, asctime population, ISO8601 and custom datefmt time formatting, Error.stack formatting, usesTime detection, and LogRecord.getMessage with %s arg substitution.	2026-03-13 23:22:10 +01:00
Tiara Rodney	7b9e88ef59	feat(formatter): implement %-style formatting, formatTime, formatError PercentFormatterStyle._format() now performs %(key)s/d/f substitution against LogRecord attributes. Formatter.format() sets record.message via getMessage() and conditionally calls formatTime() for asctime. formatTime() uses JS Date with strftime-style tokens (%Y,%m,%d,%H, %M,%S) or ISO8601 fallback. formatError() returns Error.stack. BASIC_FORMAT updated to use %(levelname)s. Fixed datefmt type in config.ts.	2026-03-13 23:14:49 +01:00
Tiara Rodney	c0ced4cda2	feat(log-record): add message, name, msg, args fields and getMessage	2026-03-13 23:09:50 +01:00
Tiara Rodney	3dce9422ae	todo(7): in-progress Implement PercentFormatterStyle._format() with %-style field substitution, Formatter.formatTime() using JS Date/Intl, and Formatter.formatError() using Error.stack. Add datetime helpers.	2026-03-13 23:05:33 +01:00
Tiara Rodney	3f424137ac	chore: add roadmap issues 10-13 Add issues for documentation, async support, OCSF formatter, and browser local storage handler from the README roadmap.	2026-03-13 23:02:46 +01:00
Tiara Rodney	2bdcb17ee6	Merge branch 'feature/6' into dev	2026-03-13 22:56:16 +01:00
Tiara Rodney	fcfbd36153	todo(6): done Added info(), warning(), error(), and critical() methods to Logger, each gated by isEnabledFor(). All level methods tested including effective level filtering.	2026-03-13 22:56:15 +01:00
Tiara Rodney	d95c8d37da	test(logger): add tests for info, warning, error, and critical methods	2026-03-13 22:56:01 +01:00
Tiara Rodney	50df6b4c37	feat(logger): add info, warning, error, and critical methods	2026-03-13 22:55:17 +01:00
Tiara Rodney	7ef841ac43	todo(6): in-progress Add info(), warning(), error(), and critical() methods to Logger.	2026-03-13 22:53:09 +01:00
Tiara Rodney	72b92af5aa	Merge branch 'bugfix/5' into dev	2026-03-13 22:50:42 +01:00
Tiara Rodney	6e82574723	todo(5): done Fixed logic bugs across manager, config, logger, handler, and formatter modules. Manager.getLogger() now correctly creates and returns loggers with hierarchy setup. Config.basicConfig() reads the correct option fields and has proper control flow. Logger isEnabledFor() caches correctly, _log() calls handle(), makeRecord() uses Object.keys(). Handler has working formatter getter, format() returns a string, and level setter no longer recurses. Formatter has a format() method. Added unit tests for all four modules.	2026-03-13 22:50:37 +01:00
Tiara Rodney	3b6b116b00	test: add unit tests for handler, logger, manager, and config Cover Handler property accessors, format delegation, emit contract, and close lifecycle. Cover Logger level methods, isEnabledFor caching, manager property assignment, handler management, debug invocation, and makeRecord extra key collision. Cover Manager getLogger hierarchy setup, placeholder fixup, disable level, and loggerClass validation. Cover basicConfig option handling, force flag, mutual exclusion of stream/filename/handlers, and formatter assignment.	2026-03-13 22:49:12 +01:00
Tiara Rodney	0b87f5516a	fix(formatter,manager): add Formatter.format(), fix Placeholder access Add format() method to Formatter class to delegate to the style's format method. Change Placeholder.loggers to public so Manager can access it for hierarchy fixup.	2026-03-13 22:42:52 +01:00
Tiara Rodney	9fed1ffe6b	fix(config): correct basicConfig option assignments and control flow Fix dateformat and style variables reading from wrong option fields (filemode instead of datefmt/style). Restructure control flow to match CPython logic: early return when handlers exist and force is not set, proper mutual exclusion of stream/filename/handlers args. Remove unreachable code block.	2026-03-13 22:41:29 +01:00
Tiara Rodney	e76d8fb77b	fix(logger): fix isEnabledFor, _log, makeRecord, and manager property Fix isEnabledFor() to correctly cache and return level check results instead of always caching false. Fix _log() to call handle() after creating the LogRecord. Fix makeRecord() to use Object.keys() and template literal. Add manager getter and fix setter to actually assign the value.	2026-03-13 22:40:46 +01:00
Tiara Rodney	340b31bc50	fix(handler): add formatter getter, fix format() return, fix level setter Add missing getter for formatter property. Fix format() to return the formatted string instead of discarding it. Fix level setter to assign to _level instead of recursing infinitely.	2026-03-13 22:40:05 +01:00
Tiara Rodney	03e3641e03	fix(manager): correct getLogger and implement hierarchy setup Fix inverted type check in getLogger() and add missing return statement. Implement _fixupParents() and _fixupChildren() to establish parent-child logger relationships based on dot-separated scope names.	2026-03-13 22:39:35 +01:00
Tiara Rodney	df0126693e	todo(5): in-progress Fix logic bugs across manager, config, logger, and handler modules. Manager.getLogger() has inverted type check and missing return. Config.basicConfig() assigns wrong option fields. Logger.isEnabledFor() always caches false, _log() never calls handle(). Handler.format() missing return and formatter getter.	2026-03-13 22:39:02 +01:00
Tiara Rodney	04e9768e89	chore: convert TODO to MIME TODO format and add issues 5-9	2026-03-13 22:38:48 +01:00
Tiara Rodney	25ec89c3b4	fix: correct jest roots and test import path	2026-03-13 22:38:41 +01:00
Tiara Rodney	0cea450c0a	chore: add eslint with typescript-eslint, align package.json scripts	2026-03-13 22:38:36 +01:00
Tiara Rodney	b7c6937219	chore: add tiara-gitflow-spec as vendor submodule	2026-03-13 22:38:27 +01:00
Rodney, Tiara	31f2d6e6f9	chore: move existing tests to sub-directory introducing sub-directories for each type of tests, so that they're easier to seperate.	2025-05-01 22:50:34 +02:00
Rodney, Tiara	e6beeec594	chore: update typedoc	2025-05-01 22:50:34 +02:00
Rodney, Tiara	b50586db8f	test(log_level): refactor	2025-05-01 22:50:34 +02:00
Rodney, Tiara	bcb65bfec5	chore: fix package namespacing	2025-05-01 22:50:33 +02:00
Rodney, Tiara	f069a0f2e4	refactor(src): introduce submodules	2025-05-01 22:50:33 +02:00
Rodney, Tiara	ab4ef2baab	doc(README): init rudimentary README	2025-05-01 22:50:33 +02:00
Rodney, Tiara	9f4d9336d2	style(ci): add commands for removing test-reports Bitbucket Pipelines has some weird default behavior on how artifacts are archived and JUnit test-reports are parsed on every subsequent run, if the output was once an artifact. It's confusing to look at via the dashboard, hence I'm adding an override to remove them beforehand.	2025-05-01 22:50:33 +02:00
Rodney, Tiara	f45e75aa50	to-do(4): in-progress	2025-05-01 22:50:14 +02:00
Rodney, Tiara	07b1228ac0	to-do(4): open	2025-05-01 22:49:51 +02:00
Rodney, Tiara	72248008b9	to-do(3): in-progress	2025-05-01 22:27:00 +02:00
Rodney, Tiara	f38f62f53e	todo(3): open	2025-05-01 22:26:30 +02:00
Rodney, Tiara	fcf45f22a3	todo(1): in-progress	2025-05-01 17:49:34 +02:00
Rodney, Tiara	15e4a5f0e1	doc(TODO): add issue #2	2025-05-01 17:49:34 +02:00
Rodney, Tiara	b159b44f7b	doc(TODO): init my poor-man's issue tracker, as I don't want to worry about the overhead of using a third-party service for this at the moment.	2025-05-01 17:49:34 +02:00
		`@ -0,0 +1 @@`
							`Subproject commit ee93479edce1da28f4abf68a362427f8d3134f80`