feat(String): add Sting Helper functions

PSConfluencePublisher/String.Tests.ps1

@@ -0,0 +1,21 @@
+#!/usr/bin/env pwsh
+$ErrorActionPreference = "Stop"
+
+BeforeAll {
+    Import-Module (Join-Path $PSScriptRoot 'PSConfluencePublisher.psd1') -Force
+}
+
+Describe 'Get-StringHash' `
+{
+    Context 'default' `
+    {
+        It 'works' `
+        {
+             $result = Get-StringHash 'foobar'
+ 
+             $result.Hash | Should -Be (
+                'C3AB8FF13720E8AD9047DD3946' + `
+                '6B3C8974E592C2FA383D4A3960714CAEF0C4F2')
+        }
+    }
+}

PSConfluencePublisher/String.psm1

@@ -0,0 +1,42 @@
+#!/usr/bin/env pwsh
+
+function Get-StringHash
+{
+    <#
+        .SYNOPSIS
+            Get hash value of a string
+
+        .DESCRIPTION
+            The Get-StringHash function is just a wrapper around the
+            Get-FileHash function and utilizes a stream for providing said
+            function with proper input values.
+
+        .OUTPUTS
+            Same as the Get-FileHash function
+
+        .EXAMPLE
+            Get-StringHash 'foobar' -Algorithm 'SHA256'
+    #>
+    Param(
+        [Parameter(Mandatory, Position = 0)] [String] $InputString,
+        [Parameter()] [String] $Algorithm = 'SHA256'
+    )
+
+    Begin
+    {
+        $stream = [IO.MemoryStream]::New()
+
+        $writer = [IO.StreamWriter]::New($stream)
+
+        $writer.Write($InputString)
+
+        $writer.Flush()
+
+        $stream.Position = 0
+    }
+
+    Process
+    {
+         Get-FileHash -InputStream $stream -Algorithm $Algorithm
+    }
+}