feat(string): init ChunkedRollingHash

tests/unit/byteb4rb1e_utils/string/test_chunked_hash.py

@@ -0,0 +1,56 @@
+import unittest
+
+from byteb4rb1e_utils.string import (
+    ChunkedRollingHash,
+    ChunkedRollingHashOptions,
+    RollingHash,
+)
+
+class test___init__(unittest.TestCase):
+    """ChunkedRollingHash.__init__()"""
+    def test_default(self):
+        """default options"""
+        result = ChunkedRollingHash(b'abcdefgh')
+
+        self.assertEqual(result._mod, ChunkedRollingHashOptions.mod)
+        self.assertEqual(result._base, ChunkedRollingHashOptions.base)
+        self.assertEqual(result._max_chunk_size, ChunkedRollingHashOptions.max_chunk_size)
+
+        control_hash = RollingHash.compute_initial_hash(
+            b'abcdefgh',
+            base = result._base,
+            mod = result._mod
+        )
+
+        self.assertEqual(result._length, 8)
+        self.assertEqual(result._chunk_count, 1)
+        self.assertEqual(len(result._chunks_hash), result._chunk_count)
+        self.assertEqual(result._hash, control_hash)
+        self.assertEqual(result._chunks_hash[0], control_hash)
+
+    def test_override(self):
+        """override of options"""
+        options = ChunkedRollingHashOptions(
+            mod = 4,
+            base = 10,
+            max_chunk_size = 5,
+        )
+        result = ChunkedRollingHash(b'abcdefgh', options)
+
+        self.assertEqual(result._mod, options.mod)
+        self.assertEqual(result._base, options.base)
+        self.assertEqual(result._max_chunk_size, options.max_chunk_size)
+
+        control_hash1 = RollingHash.compute_initial_hash(
+            b'abcde',
+            base = result._base,
+            mod = result._mod
+        )
+        control_hash2 = RollingHash.compute_initial_hash(
+            b'fgh',
+            base = result._base,
+            mod = result._mod
+        )
+
+        self.assertEqual(result._chunks_hash[0], control_hash1)
+        self.assertEqual(result._chunks_hash[1], control_hash2)