Properly handle .keep_dir files

Handle ValueError when trying to parse .keep_dir files that hold
no package atom, also add some tests.

Signed-off-by: gcarq <[email protected]>

lostfiles.py

@@ -4,6 +4,7 @@
 import argparse
 import itertools
 import os
+import sys
 from glob import glob
 
 import portage
@@ -347,10 +348,9 @@ def process_directory(dirpath: str, filenames: list[str], strict: bool, tracked:
         if not name.startswith(".keep_"):
             continue
 
-        atom = resolve_pkg_from_keepfile(name)
-        if is_pkg_installed(atom):
-            raise IgnoreDirectory()
-        break
+        if atom := resolve_pkg_from_keepfile(name):
+            if is_pkg_installed(atom):
+                raise IgnoreDirectory()
 
     if not strict:
         paths = resolve_symlinks(dirpath)
@@ -383,14 +383,22 @@ def resolve_symlinks(*paths: str) -> set[str]:
     return set(itertools.chain.from_iterable((path, os.path.realpath(path)) for path in paths))
 
 
-def resolve_pkg_from_keepfile(filename: str) -> str:
+def resolve_pkg_from_keepfile(filename: str) -> str | None:
     """
     Returns the package atom from the given .keep file,
+    or None if the keepfile cannot be parsed.
     for example: .keep_net-print_cups-0 -> net-print/cups
     """
-    _, category, remainder = filename.split("_", maxsplit=2)
-    package, _ = remainder.rsplit("-", maxsplit=1)
-    return f"{category}/{package}"
+    if filename == '.keep_dir':
+        return None
+
+    try:
+        _, category, remainder = filename.split("_", maxsplit=2)
+        package, _ = remainder.rsplit("-", maxsplit=1)
+        return f"{category}/{package}"
+    except ValueError:
+        print(f"Failed to parse package from keepfile: {filename}, this is a bug", file=sys.stderr)
+        return None
 
 
 def is_pkg_installed(atom: str) -> bool:

pyproject.toml

@@ -10,6 +10,9 @@ authors = [
   {name = 'Michael Egger', email = '[email protected]'},
 ]
 
+[dev-dependencies]
+test = ["pytest"]
+
 [project.scripts]
 lostfiles = "lostfiles:main"
 

tests/test_lostfiles.py

@@ -0,0 +1,16 @@
+from unittest.mock import patch
+
+from lostfiles import resolve_pkg_from_keepfile, should_ignore_path
+
+
+def test_resolve_pkg_from_keepfile():
+    assert resolve_pkg_from_keepfile(".keep_net-print_cups-0") == "net-print/cups"
+    assert resolve_pkg_from_keepfile(".keep_sys-apps_systemd-0") == "sys-apps/systemd"
+    assert resolve_pkg_from_keepfile(".keep_dir") is None
+
+
+@patch("lostfiles.IGNORED_PATHS", {"/ignored"})
+def test_should_ignore_path(*args, **kwargs):
+    assert should_ignore_path("/ignored") is True
+    assert should_ignore_path("/not_ignored") is False
+    assert should_ignore_path("/not_ignored/.keep") is True