"""Unit tests for pylint parsers module."""
import json
from mcp_code_checker.code_checker_pylint.parsers import parse_pylint_json_output
class TestParsePylintJsonOutput:
"""Test cases for parse_pylint_json_output function."""
def test_parse_valid_json_output(self) -> None:
"""Test parsing valid JSON output from pylint."""
json_data = [
{
"type": "error",
"module": "test_module",
"obj": "test_function",
"line": 10,
"column": 5,
"path": "/path/to/file.py",
"symbol": "undefined-variable",
"message": "Undefined variable 'x'",
"message-id": "E0602",
},
{
"type": "warning",
"module": "test_module",
"obj": "test_function2",
"line": 20,
"column": 10,
"path": "/path/to/file.py",
"symbol": "unused-variable",
"message": "Unused variable 'y'",
"message-id": "W0612",
},
]
raw_output = json.dumps(json_data)
messages, error = parse_pylint_json_output(raw_output)
assert error is None
assert len(messages) == 2
# Check first message
assert messages[0].type == "error"
assert messages[0].module == "test_module"
assert messages[0].obj == "test_function"
assert messages[0].line == 10
assert messages[0].column == 5
assert messages[0].path == "/path/to/file.py"
assert messages[0].symbol == "undefined-variable"
assert messages[0].message == "Undefined variable 'x'"
assert messages[0].message_id == "E0602"
# Check second message
assert messages[1].type == "warning"
assert messages[1].message_id == "W0612"
def test_parse_empty_output(self) -> None:
"""Test parsing empty output."""
messages, error = parse_pylint_json_output("")
assert error is None
assert messages == []
def test_parse_whitespace_only_output(self) -> None:
"""Test parsing whitespace-only output."""
messages, error = parse_pylint_json_output(" \n \t ")
assert error is None
assert messages == []
def test_parse_empty_json_array(self) -> None:
"""Test parsing empty JSON array."""
messages, error = parse_pylint_json_output("[]")
assert error is None
assert messages == []
def test_parse_invalid_json(self) -> None:
"""Test parsing invalid JSON."""
raw_output = "This is not valid JSON"
messages, error = parse_pylint_json_output(raw_output)
assert messages == []
assert error is not None
assert "Failed to parse Pylint JSON output" in error
assert "This is not valid JSON" in error
def test_parse_json_object_instead_of_array(self) -> None:
"""Test parsing JSON object instead of expected array."""
raw_output = json.dumps({"type": "error", "message": "test"})
messages, error = parse_pylint_json_output(raw_output)
assert messages == []
assert error is not None
assert "Expected JSON array from pylint, got dict" in error
def test_parse_json_with_non_dict_items(self) -> None:
"""Test parsing JSON array with non-dict items."""
json_data = [
{
"type": "error",
"module": "test_module",
"obj": "",
"line": 1,
"column": 1,
"path": "test.py",
"symbol": "test",
"message": "Test message",
"message-id": "E0001",
},
"This is a string, not a dict",
42,
{
"type": "warning",
"module": "test_module2",
"obj": "",
"line": 2,
"column": 1,
"path": "test2.py",
"symbol": "test2",
"message": "Test message 2",
"message-id": "W0001",
},
]
raw_output = json.dumps(json_data)
messages, error = parse_pylint_json_output(raw_output)
assert error is None
assert len(messages) == 2 # Only dict items are processed
assert messages[0].message_id == "E0001"
assert messages[1].message_id == "W0001"
def test_parse_json_with_missing_fields(self) -> None:
"""Test parsing JSON with missing fields."""
json_data = [
{
"type": "error",
# Missing most fields
},
{
"type": "warning",
"module": "test_module",
"line": 10,
# Missing other fields
},
]
raw_output = json.dumps(json_data)
messages, error = parse_pylint_json_output(raw_output)
assert error is None
assert len(messages) == 2
# Check default values for missing fields
assert messages[0].type == "error"
assert messages[0].module == ""
assert messages[0].obj == ""
assert messages[0].line == -1
assert messages[0].column == -1
assert messages[0].path == ""
assert messages[0].symbol == ""
assert messages[0].message == ""
assert messages[0].message_id == ""
def test_parse_very_long_output(self) -> None:
"""Test parsing very long output (error message truncation)."""
raw_output = "x" * 300 # Invalid JSON, longer than 200 chars
messages, error = parse_pylint_json_output(raw_output)
assert messages == []
assert error is not None
assert "Failed to parse Pylint JSON output" in error
assert "First 200 chars of output:" in error
assert "xxx..." in error # Should be truncated
