Ensure test directory ignore rules are only added if the /tests exists (#1232)

nathanjmcdougall · web-flow · commit de7274333235 · 2025-12-28T23:24:36.000+13:00
* Ensure test directory ignore rules are only added if the tests directory exists

* Rename test for clarity

* Update tests to reflect new behaviour

* Update tests to reflect new behaviour
diff --git a/src/usethis/_tool/impl/ruff.py b/src/usethis/_tool/impl/ruff.py
@@ -482,9 +482,11 @@ def apply_rule_config(self, rule_config: RuleConfig) -> None:
             alert_only=(is_selected or is_ignored) or usethis_config.alert_only,
             instruct_only=(is_selected or is_ignored) or usethis_config.instruct_only,
         ):
-            self.ignore_rules_in_glob(
-                rule_config.tests_unmanaged_ignored, glob="tests/**"
-            )
+            # Only add test directory ignore rules if the tests directory exists
+            if (usethis_config.cpd() / "tests").exists():
+                self.ignore_rules_in_glob(
+                    rule_config.tests_unmanaged_ignored, glob="tests/**"
+                )
 
     def remove_rule_config(self, rule_config: RuleConfig) -> None:
         """Remove the Ruff rules associated with a rule config from the project.
diff --git a/tests/usethis/_core/test_core_tool.py b/tests/usethis/_core/test_core_tool.py
@@ -1468,6 +1468,7 @@ def test_no_duplicate_inp_rules(self, tmp_path: Path):
 
             # Arrange
             (tmp_path / "ruff.toml").touch()
+            (tmp_path / "tests").mkdir()
 
             with change_cwd(tmp_path), files_manager():
                 # ... preparing for duplicate call
@@ -1496,6 +1497,7 @@ def test_inp_rules_not_selected_for_tests_dir(
         ):
             # Arrange
             (uv_init_dir / "ruff.toml").touch()
+            (uv_init_dir / "tests").mkdir()
 
             with change_cwd(uv_init_dir), files_manager():
                 # Act
@@ -1532,6 +1534,7 @@ def test_message_for_already_selected_but_needs_ignoring(
 [lint]
 select = ["INP"]
 """)
+            (uv_init_dir / "tests").mkdir()
 
             with change_cwd(uv_init_dir), files_manager():
                 # Act
@@ -1573,6 +1576,7 @@ def test_inp_rules_dont_break_config(self, uv_init_dir: Path):
 lint.select = [ "A", "C4", "E4", "E7", "E9", "F", "FLY", "FURB", "I", "INP", "PLE", "PLR", "PT", "RUF", "SIM", "UP" ]
 lint.ignore = [ "PLR2004", "SIM108" ]
 """)
+            (uv_init_dir / "tests").mkdir()
 
             with change_cwd(uv_init_dir), files_manager():
                 # Act
@@ -2718,6 +2722,7 @@ def test_import_linter_inp_rules(self, tmp_path: Path):
             with change_cwd(tmp_path), files_manager():
                 # Arrange
                 use_import_linter()
+                (tmp_path / "tests").mkdir()
 
                 # Act
                 (tmp_path / "ruff.toml").touch()
diff --git a/tests/usethis/_ui/interface/test_tool.py b/tests/usethis/_ui/interface/test_tool.py
@@ -229,6 +229,45 @@ def test_how(self, tmp_path: Path):
 """  # noqa: RUF001
         )
 
+    def test_when_test_dir_doesnt_exist(self, tmp_path: Path):
+        # Arrange
+        (tmp_path / "src").mkdir()
+        (tmp_path / "src" / "example").mkdir()
+        (tmp_path / "src" / "example" / "__init__.py").touch()
+        (tmp_path / "src" / "example" / "module.py").touch()
+        (tmp_path / "pyproject.toml").write_text("""\
+[project]
+name = "example"
+version = "0.1.0"
+
+[tool.ruff]
+line-length = 88
+""")
+        # Note: No tests directory created
+
+        # Act
+        runner = CliRunner()
+        with change_cwd(tmp_path):
+            result = runner.invoke_safe(app, ["import-linter", "--frozen"])
+
+            # Assert
+            assert result.exit_code == 0, result.output
+
+            with files_manager():
+                pyproject = PyprojectTOMLManager()
+                # Should not have per-file-ignores for tests/** since tests dir doesn't exist
+                if ["tool", "ruff", "lint", "per-file-ignores"] in pyproject:
+                    per_file_ignores = pyproject[
+                        ["tool", "ruff", "lint", "per-file-ignores"]
+                    ]
+                    assert "tests/**" not in per_file_ignores, (
+                        "Should not add tests/** ignore when tests directory doesn't exist"
+                    )
+                else:
+                    # If per-file-ignores doesn't exist at all, that's also correct
+                    # (no tests directory means no test-specific ignores needed)
+                    pass
+
 
 class TestPyprojectTOML:
     def test_add(self, tmp_path: Path):
