Add tests

pylint/lint/expand_modules.py

@@ -37,14 +37,13 @@ def discover_package_path(
     for source_root in source_roots:
         source_root = os.path.realpath(os.path.expanduser(source_root))
         if os.path.commonpath([source_root, dirname]) == source_root:
-            #return cast(Sequence[str], [source_root])
             return [source_root]
 
     if len(source_roots) != 0:
         return source_roots
 
     # Fall back to legacy discovery by looking for __init__.py upwards as
-    # it's the only way given that source root was not found or was not provided
+    # source_roots was not provided
     while True:
         if not os.path.exists(os.path.join(dirname, "__init__.py")):
             return [dirname]

tests/lint/unittest_expand_modules.py

@@ -14,7 +14,7 @@
 import pytest
 
 from pylint.checkers import BaseChecker
-from pylint.lint.expand_modules import _is_in_ignore_list_re, expand_modules
+from pylint.lint.expand_modules import _is_in_ignore_list_re, discover_package_path, expand_modules
 from pylint.testutils import CheckerTestCase, set_config
 from pylint.typing import MessageDefinitionTuple, ModuleDescriptionDict
 
@@ -306,3 +306,13 @@ def test_expand_modules_with_ignore(
         )
         assert modules == expected
         assert not errors
+
+def test_discover_package_path_no_source_root_overlap(tmp_path):
+    """Test whether source_roots is returned even if module doesn't overlap
+       with source_roots"""
+    source_roots = [tmp_path]
+    package_paths = discover_package_path(__file__, source_roots)
+
+    expected = source_roots
+    assert(package_paths == expected)
+

tests/regrtest_data/source_roots_implicit_namespace_pkg/tests/test_app.py

@@ -0,0 +1,3 @@
+""" Test for source-roots import for implicit namespace package. The following 
+    should succeed."""
+import namespacepkg.pkg.app

tests/regrtest_data/source_roots_src_layout/tests/test_app.py

@@ -0,0 +1,2 @@
+""" Test for import. The following import should work if source-roots is setup correctly """
+import mypkg.app

tests/test_self.py

@@ -208,6 +208,16 @@ def test_exit_zero(self) -> None:
             ["--exit-zero", join(HERE, "regrtest_data", "syntax_error.py")], code=0
         )
 
+    @pytest.mark.parametrize(
+        "repo", ["source_roots_src_layout", "source_roots_implicit_namespace_pkg"]
+    )
+    def test_source_roots_src_layout(self, repo: str) -> None:
+        repo = join(HERE, "regrtest_data",repo)
+        src_path = join(repo, "src")
+        self._runtest(
+            ["-d", "unused-import", f"--source-roots={src_path}", repo], code=0
+        )
+
     def test_nonexistent_config_file(self) -> None:
         self._runtest(["--rcfile=/tmp/this_file_does_not_exist"], code=32)