test: cover anchored exclude pattern behavior

yangfan-yf-yf · Aug 9, 2026 · Aug 9, 2026 · Sep 14, 2026 · Aug 9, 2026 · db3dfc930f030a8e387cf86b71a7643c5e38cedf
commit db3dfc930f030a8e387cf86b71a7643c5e38cedf
diff --git a/cpplint.py b/cpplint.py
@@ -270,7 +270,8 @@
     "exclude_files" allows to specify a regular expression to be matched against
     the file path relative to the CPPLINT.cfg directory. Paths use "/" as the
     separator on all platforms. If the expression matches, the file is skipped
-    and not run through the linter.
+    and not run through the linter. To exclude a directory subtree, use a prefix
+    pattern such as "^bar/" rather than an anchored directory pattern like "^bar$".
 
     "linelength" allows to specify the allowed line length for the project.
 

diff --git a/cpplint_unittest.py b/cpplint_unittest.py
@@ -7298,6 +7298,7 @@ def _write_file(path, content=""):
             ("baz.cc", "^baz[.]cc$", False),
             ("bar/baz.cc", "^bar/baz[.]cc$", False),
             ("bar/qux.cc", "^bar/baz[.]cc$", True),
+            ("bar/baz.cc", "^bar$", True),
             ("bar/baz.cc", "^bar/", False),
         ],
     )