chore: import upstream snapshot with attribution

tests/test_errors.py

@@ -0,0 +1,67 @@
+"""Tests for the centralized error code / HTTP status mapping."""
+
+from __future__ import annotations
+
+import pytest
+
+from omnigent.errors import _CODE_TO_HTTP_STATUS, ErrorCode, OmnigentError
+
+
+def test_harness_protocol_violation_string_value() -> None:
+    """The error code's string value is what appears in JSON responses.
+
+    Clients dispatch on this string; renaming it is a wire-protocol
+    change. If this assertion flips, every external consumer that
+    branches on ``error.code == "harness_protocol_violation"`` breaks.
+    """
+    assert ErrorCode.HARNESS_PROTOCOL_VIOLATION == "harness_protocol_violation"
+
+
+def test_harness_protocol_violation_maps_to_500() -> None:
+    """Harness protocol violations are server-side bugs in the harness wrap.
+
+    They surface as HTTP 500 (no client action can fix them — the harness
+    implementation needs investigation). If this drifts to 4xx, callers
+    might mistakenly retry or attempt user-side remediation.
+    """
+    assert _CODE_TO_HTTP_STATUS[ErrorCode.HARNESS_PROTOCOL_VIOLATION] == 500
+
+
+def test_omnigent_error_with_harness_violation_code_returns_500() -> None:
+    """End-to-end: OmnigentError(code=HARNESS_PROTOCOL_VIOLATION).http_status == 500.
+
+    Exercises the public API path that FastAPI's exception handler uses
+    to map an error to an HTTP status. If this fails, harness protocol
+    violations would surface to clients as 500-with-default rather than
+    500-with-the-right-code, masking the bug class.
+    """
+    err = OmnigentError(
+        "harness emitted response.completed with outstanding elicitations",
+        code=ErrorCode.HARNESS_PROTOCOL_VIOLATION,
+    )
+    assert err.http_status == 500
+    assert err.code == ErrorCode.HARNESS_PROTOCOL_VIOLATION
+    assert "outstanding elicitations" in err.message
+
+
+@pytest.mark.parametrize(
+    "code,expected_status",
+    [
+        (ErrorCode.NOT_FOUND, 404),
+        (ErrorCode.INVALID_INPUT, 400),
+        (ErrorCode.ALREADY_EXISTS, 409),
+        (ErrorCode.CONFLICT, 409),
+        (ErrorCode.INTERNAL_ERROR, 500),
+        (ErrorCode.HARNESS_PROTOCOL_VIOLATION, 500),
+    ],
+)
+def test_all_error_codes_have_http_status_mapping(code: str, expected_status: int) -> None:
+    """Every public ErrorCode value MUST appear in the mapping.
+
+    A code without a mapping silently defaults to 500 in
+    OmnigentError.http_status — not wrong, but it hides drift.
+    This parametrized test makes adding a new ErrorCode without
+    updating the mapping a noisy failure rather than a silent
+    default.
+    """
+    assert _CODE_TO_HTTP_STATUS[code] == expected_status