swev-id: pytest-dev__pytest-7982

src/_pytest/pathlib.py

@@ -1,5 +1,6 @@
 import atexit
 import contextlib
+import errno
 import fnmatch
 import importlib.util
 import itertools
@@ -549,17 +550,40 @@ def resolve_package_path(path: Path) -> Optional[Path]:
 
 
 def visit(
-    path: str, recurse: Callable[["os.DirEntry[str]"], bool]
+    path: str,
+    recurse: Callable[["os.DirEntry[str]"], bool],
+    *,
+    _seen: Optional[Set[str]] = None,
 ) -> Iterator["os.DirEntry[str]"]:
     """Walk a directory recursively, in breadth-first order.
 
     Entries at each directory level are sorted.
     """
+    if _seen is None:
+        _seen = set()
+
+    real_path = os.path.realpath(path)
+    if real_path in _seen:
+        return
+    _seen.add(real_path)
+
     entries = sorted(os.scandir(path), key=lambda entry: entry.name)
     yield from entries
     for entry in entries:
-        if entry.is_dir(follow_symlinks=False) and recurse(entry):
-            yield from visit(entry.path, recurse)
+        try:
+            is_directory = entry.is_dir(follow_symlinks=True)
+        except OSError as exc:
+            if exc.errno in (
+                errno.ENOENT,
+                errno.ENOTDIR,
+                errno.ELOOP,
+                errno.EACCES,
+                errno.EPERM,
+            ):
+                continue
+            raise
+        if is_directory and recurse(entry):
+            yield from visit(entry.path, recurse, _seen=_seen)
 
 
 def absolutepath(path: Union[Path, str]) -> Path:

testing/test_collection.py

@@ -1256,6 +1256,32 @@ def test_collect_sub_with_symlinks(use_pkg, testdir):
     )
 
 
+def test_collect_symlinked_directory_argument(testdir):
+    target = testdir.mkdir("real_dir")
+    target.join("test_linked.py").write("def test_linked(): pass")
+
+    link = testdir.tmpdir.join("link_dir")
+    symlink_or_skip(target, link, target_is_directory=True)
+
+    result = testdir.runpytest("-v", str(link))
+    result.stdout.fnmatch_lines(
+        ("link_dir/test_linked.py::test_linked PASSED*", "*1 passed in*",)
+    )
+
+
+def test_collect_symlinked_subdirectory(testdir):
+    target = testdir.mkdir("real_pkg")
+    target.join("test_inside.py").write("def test_inside(): pass")
+
+    root = testdir.mkdir("root")
+    symlink_or_skip(target, root.join("link_pkg"), target_is_directory=True)
+
+    result = testdir.runpytest("-v", str(root))
+    result.stdout.fnmatch_lines(
+        ("root/link_pkg/test_inside.py::test_inside PASSED*", "*1 passed in*",)
+    )
+
+
 def test_collector_respects_tbstyle(testdir):
     p1 = testdir.makepyfile("assert 0")
     result = testdir.runpytest(p1, "--tb=native")