Primer tests "à la mypy" (#5173)

* Add changelog and warning about unstable API in testutil

* Add primer tests, (running pylint on external libs during tests)

In order to anticipate crash/fatal messages, false positives are harder
to anticipate. Follow-up will be #5359 and later on #5364 

Add '__tracebackhide__ = True' so the traceback is manageable

Co-authored-by: Daniël van Noord <13665637+DanielNoord@users.noreply.github.com>

1 files changed, 48 insertions, 0 deletions

diff --git a/tests/testutils/test_package_to_lint.py b/tests/testutils/test_package_to_lint.py
new file mode 100644
index 000000000..bf90db3e7
--- /dev/null
+++ b/tests/testutils/test_package_to_lint.py
@@ -0,0 +1,48 @@
+# Licensed under the GPL: https://www.gnu.org/licenses/old-licenses/gpl-2.0.html
+# For details: https://github.com/PyCQA/pylint/blob/main/LICENSE
+
+from pylint.testutils.primer import PRIMER_DIRECTORY_PATH, PackageToLint
+
+
+def test_package_to_lint() -> None:
+    """Test that the PackageToLint is instantiated correctly."""
+    expected_dir_path = PRIMER_DIRECTORY_PATH / "vimeo" / "graph-explorer"
+    expected_path_to_lint = expected_dir_path / "graph_explorer"
+    expected_pylintrc_path = expected_dir_path / ".pylintrcui"
+
+    args = ["--ignore-pattern='re*'"]
+    package_to_lint = PackageToLint(
+        url="https://github.com/vimeo/graph-explorer.git",
+        branch="main",
+        directories=["graph_explorer"],
+        pylintrc_relpath=".pylintrcui",
+        pylint_additional_args=args,
+    )
+
+    assert package_to_lint.url == "https://github.com/vimeo/graph-explorer.git"
+    assert package_to_lint.branch == "main"
+    assert package_to_lint.directories == ["graph_explorer"]
+    assert package_to_lint.pylintrc_relpath == ".pylintrcui"
+    assert package_to_lint.pylint_additional_args == args
+    assert package_to_lint.paths_to_lint == [str(expected_path_to_lint)]
+    assert package_to_lint.clone_directory == expected_dir_path
+    assert package_to_lint.pylintrc == expected_pylintrc_path
+    expected_args = [
+        str(expected_path_to_lint),
+        f"--rcfile={expected_pylintrc_path}",
+    ] + args
+    assert package_to_lint.pylint_args == expected_args
+
+
+def test_package_to_lint_default_value() -> None:
+    """Test that the PackageToLint is instantiated correctly with default value."""
+    package_to_lint = PackageToLint(
+        url="https://github.com/pallets/flask.git",
+        branch="main",
+        directories=["src/flask"],  # Must work on Windows (src\\flask)
+    )
+    assert package_to_lint.pylintrc is None
+    expected_path_to_lint = (
+        PRIMER_DIRECTORY_PATH / "pallets" / "flask" / "src" / "flask"
+    )
+    assert package_to_lint.pylint_args == [str(expected_path_to_lint)]