chunker and ui

tests/chunker/test_exceptions.py

@@ -0,0 +1,69 @@
+"""
+Tests for exception hierarchy — catch patterns, attributes.
+
+Demonstrates: TDD (Interview Topic 8) — testing exception design.
+"""
+
+import pytest
+
+from core.chunker.exceptions import (
+    ChunkChecksumError,
+    ChunkError,
+    ChunkReadError,
+    PipelineError,
+    ProcessingError,
+    ProcessorFailureError,
+    ProcessorTimeoutError,
+    ReassemblyError,
+)
+
+
+class TestExceptionHierarchy:
+    """Verify the exception class hierarchy and catch patterns."""
+
+    def test_pipeline_error_is_base(self):
+        """All chunker exceptions inherit from PipelineError."""
+        assert issubclass(ChunkError, PipelineError)
+        assert issubclass(ProcessingError, PipelineError)
+        assert issubclass(ReassemblyError, PipelineError)
+
+    def test_chunk_error_subtypes(self):
+        """ChunkReadError and ChunkChecksumError are ChunkErrors."""
+        assert issubclass(ChunkReadError, ChunkError)
+        assert issubclass(ChunkChecksumError, ChunkError)
+
+    def test_processing_error_subtypes(self):
+        """ProcessorTimeoutError and ProcessorFailureError are ProcessingErrors."""
+        assert issubclass(ProcessorTimeoutError, ProcessingError)
+        assert issubclass(ProcessorFailureError, ProcessingError)
+
+    def test_catch_pipeline_error_catches_all(self):
+        """Catching PipelineError catches any subtype."""
+        with pytest.raises(PipelineError):
+            raise ChunkReadError("test")
+
+        with pytest.raises(PipelineError):
+            raise ReassemblyError("test")
+
+    def test_checksum_error_attributes(self):
+        """ChunkChecksumError carries sequence, expected, actual."""
+        err = ChunkChecksumError(sequence=5, expected="aaa", actual="bbb")
+        assert err.sequence == 5
+        assert err.expected == "aaa"
+        assert err.actual == "bbb"
+        assert "5" in str(err)
+
+    def test_timeout_error_attributes(self):
+        """ProcessorTimeoutError carries sequence and timeout."""
+        err = ProcessorTimeoutError(sequence=3, timeout=30.0)
+        assert err.sequence == 3
+        assert err.timeout == 30.0
+
+    def test_failure_error_attributes(self):
+        """ProcessorFailureError carries sequence, retries, original error."""
+        original = RuntimeError("boom")
+        err = ProcessorFailureError(sequence=1, retries=3, original_error=original)
+        assert err.sequence == 1
+        assert err.retries == 3
+        assert err.original_error is original
+        assert "boom" in str(err)