Add tests for different configs in different directories

Author: Aleksey Petryankin

tests/config/test_per_directory_config.py

@@ -2,8 +2,16 @@
 # For details: https://github.com/pylint-dev/pylint/blob/main/LICENSE
 # Copyright (c) https://github.com/pylint-dev/pylint/blob/main/CONTRIBUTORS.txt
 
+from __future__ import annotations
+
+import os
+import os.path
 from pathlib import Path
 
+import pytest
+from pytest import CaptureFixture
+
+from pylint.lint import Run as LintRun
 from pylint.testutils._run import _Run as Run
 
 
@@ -21,3 +29,96 @@ def test_fall_back_on_base_config(tmp_path: Path) -> None:
         f.write("1")
     Run([str(test_file)], exit=False)
     assert id(runner.linter.config) == id(runner.linter._base_config)
+
+
+def _create_subconfig_test_fs(tmp_path: Path) -> tuple[Path, Path, Path]:
+    level1_dir = tmp_path / "level1_dir"
+    conf_file1 = level1_dir / "pylintrc"
+    test_file1 = level1_dir / "a.py"
+    subdir = level1_dir / "sub"
+    conf_file2 = subdir / "pylintrc"
+    test_file2 = subdir / "b.py"
+    os.makedirs(subdir)
+    test_file_text = "#NOTE_A\n#NOTE_B\n#TODO\n"
+    test_file1.write_text(test_file_text)
+    test_file2.write_text(test_file_text)
+    conf1 = "[MISCELLANEOUS]\nnotes=NOTE_A,NOTE_B"
+    conf2 = "[MISCELLANEOUS]\nnotes=NOTE_B"
+    conf_file1.write_text(conf1)
+    conf_file2.write_text(conf2)
+    return (level1_dir, test_file1, test_file2)
+
+
+def _create_parent_subconfig_fs(tmp_path: Path) -> Path:
+    level1_dir = tmp_path / "package"
+    conf_file = level1_dir / "pylintrc"
+    subdir = level1_dir / "sub"
+    test_file = subdir / "b.py"
+    os.makedirs(subdir)
+    test_file_text = "#NOTE_A\n#NOTE_B\n#TODO\n"
+    test_file.write_text(test_file_text)
+    conf = "[MISCELLANEOUS]\nnotes=NOTE_A,NOTE_B"
+    conf_file.write_text(conf)
+    return test_file
+
+
+@pytest.mark.parametrize(
+    "local_config_args",
+    [["--use-local-configs=y"], ["--use-local-configs=y", "--use-parent-configs=y"]],
+)
+@pytest.mark.parametrize("start_dir_modificator", [".", ".."])
+def test_subconfig_vs_root_config(
+    tmp_path: Path,
+    capsys: CaptureFixture,
+    local_config_args: list[str],
+    start_dir_modificator: str,
+) -> None:
+    """Test that each checked file uses config from its own
+    or closest parent directory.
+    """
+    level1_dir, test_file1, test_file2 = _create_subconfig_test_fs(tmp_path)
+    start_dir = (level1_dir / start_dir_modificator).resolve()
+    orig_cwd = os.getcwd()
+    os.chdir(start_dir)
+    # _Run adds --rcfile, which overrides config from cwd
+    LintRun([*local_config_args, str(test_file1)], exit=False)
+    output1 = capsys.readouterr().out.replace("\\n", "\n")
+    LintRun([*local_config_args, str(test_file2)], exit=False)
+    output2 = capsys.readouterr().out.replace("\\n", "\n")
+    os.chdir(orig_cwd)
+
+    # different results for identical files because of different configs
+    assert "NOTE_A" in output1
+    assert "NOTE_A" not in output2
+
+
+def test_subconfig_vs_cli_arg(tmp_path: Path, capsys: CaptureFixture) -> None:
+    """Test that cli args have priority over subconfigs."""
+    test_root, test_file1, test_file2 = _create_subconfig_test_fs(tmp_path)
+    orig_cwd = os.getcwd()
+    os.chdir(test_root)
+    Run(["--notes=FIXME", "--use-local-configs=y", str(test_file1)], exit=False)
+    output1 = capsys.readouterr().out.replace("\\n", "\n")
+    Run(["--notes=FIXME", "--use-local-configs=y", str(test_file2)], exit=False)
+    output2 = capsys.readouterr().out.replace("\\n", "\n")
+    os.chdir(orig_cwd)
+
+    # check that cli arg overrides default value
+    assert "TODO" not in output1
+    # notes=FIXME in cli should override all pylintrc configs
+    assert "NOTE_B" not in output1
+    assert "NOTE_B" not in output2
+
+
+def test_subconfig_in_parent(tmp_path: Path, capsys: CaptureFixture) -> None:
+    """Test that searching local configs in parent directories works."""
+    test_file = _create_parent_subconfig_fs(tmp_path)
+    orig_cwd = os.getcwd()
+    os.chdir(tmp_path)
+    Run(["--use-parent-configs=y", "--use-local-configs=y", str(test_file)], exit=False)
+    output1 = capsys.readouterr().out.replace("\\n", "\n")
+    os.chdir(orig_cwd)
+
+    # check that file is linted with config from ../, which is not a cwd
+    assert "TODO" not in output1
+    assert "NOTE_A" in output1