gh-135801: Improve filtering by module in warn_explicit() without module argument

Doc/library/warnings.rst

@@ -487,7 +487,14 @@ Available Functions
  ignored.
 
  *module*, if supplied, should be the module name.
- If no module is passed, the filename with ``.py`` stripped is used.
+ If no module is passed, the module regular expression in
+ :ref:`warnings filter <warning-filter>` will be tested against the module
+ names constructed from the path components starting from all parent
+ directories (with ``/__init__.py``, ``.py`` and, on Windows, ``.pyw``
+ stripped) and against the filename with ``.py`` stripped.
+ For example, when the filename is ``'/path/to/package/module.py'``, it will
+ be tested against ``'path.to.package.module'``, ``'to.package.module'``
+ ``'package.module'``, ``'module'``, and ``'/path/to/package/module'``.
 
  *registry*, if supplied, should be the ``__warningregistry__`` dictionary
  of the module.
@@ -506,6 +513,10 @@ Available Functions
  .. versionchanged:: 3.6
  Add the *source* parameter.
 
+ .. versionchanged:: next
+ If no module is passed, test the filter regular expression against
+ module names created from the path, not only the path itself.
+
 
 .. function:: showwarning(message, category, filename, lineno, file=None, line=None)
 

Doc/whatsnew/3.15.rst

@@ -611,6 +611,18 @@ unittest
  (Contributed by Garry Cairns in :gh:`134567`.)
 
 
+warnings
+--------
+
+* Improve filtering by module in :func:`warnings.warn_explicit` if no *module*
+ argument is passed.
+ It now tests the module regular expression in the warnings filter not only
+ against the filename with ``.py`` stripped, but also against module names
+ constructed starting from different parent directories of the filename
+ (with ``/__init__.py``, ``.py`` and, on Windows, ``.pyw`` stripped).
+ (Contributed by Serhiy Storchaka in :gh:`135801`.)
+
+
 venv
 ----
 

Lib/_py_warnings.py

@@ -520,20 +520,50 @@ def warn(message, category=None, stacklevel=1, source=None,
  )
 
 
+def _match_filename(pattern, filename, *, MS_WINDOWS=(sys.platform == 'win32')):
+ if not filename:
+ return pattern.match('<unknown>') is not None
+ if filename[0] == '<' and filename[-1] == '>':
+ return pattern.match(filename) is not None
+
+ is_py = (filename[-3:].lower() == '.py'
+ if MS_WINDOWS else
+ filename.endswith('.py'))
+ if is_py:
+ filename = filename[:-3]
+ if pattern.match(filename): # for backward compatibility
+ return True
+ if MS_WINDOWS:
+ if not is_py and filename[-4:].lower() == '.pyw':
+ filename = filename[:-4]
+ is_py = True
+ if is_py and filename[-9:].lower() in (r'\__init__', '/__init__'):
+ filename = filename[:-9]
+ filename = filename.replace('\\', '/')
+ else:
+ if is_py and filename.endswith('/__init__'):
+ filename = filename[:-9]
+ filename = filename.replace('/', '.')
+ i = 0
+ while True:
+ if pattern.match(filename, i):
+ return True
+ i = filename.find('.', i) + 1
+ if not i:
+ return False
+
+
 def warn_explicit(message, category, filename, lineno,
  module=None, registry=None, module_globals=None,
  source=None):
  lineno = int(lineno)
- if module is None:
- module = filename or "<unknown>"
- if module[-3:].lower() == ".py":
- module = module[:-3] # XXX What about leading pathname?
  if isinstance(message, Warning):
  text = str(message)
  category = message.__class__
  else:
  text = message
  message = category(message)
+ modules = None
  key = (text, category, lineno)
  with _wm._lock:
  if registry is None:
@@ -549,9 +579,11 @@ def warn_explicit(message, category, filename, lineno,
  action, msg, cat, mod, ln = item
  if ((msg is None or msg.match(text)) and
  issubclass(category, cat) and
- (mod is None or mod.match(module)) and
- (ln == 0 or lineno == ln)):
- break
+ (ln == 0 or lineno == ln) and
+ (mod is None or (_match_filename(mod, filename)
+ if module is None else
+ mod.match(module)))):
+ break
  else:
  action = _wm.defaultaction
  # Early exit actions

Lib/test/test_ast/test_ast.py

@@ -13,6 +13,7 @@
 import textwrap
 import types
 import unittest
+import warnings
 import weakref
 from io import StringIO
 from pathlib import Path
@@ -1069,6 +1070,19 @@ def test_tstring(self):
  self.assertIsInstance(tree.body[0].value.values[0], ast.Constant)
  self.assertIsInstance(tree.body[0].value.values[1], ast.Interpolation)
 
+ def test_filter_syntax_warnings_by_module(self):
+ filename = support.findfile('test_import/data/syntax_warnings.py')
+ with open(filename, 'rb') as f:
+ source = f.read()
+ with warnings.catch_warnings(record=True) as wlog:
+ warnings.simplefilter('error')
+ warnings.filterwarnings('always', module=r'<unknown>\z')
+ ast.parse(source)
+ self.assertEqual(sorted(wm.lineno for wm in wlog), [4, 7, 10])
+ for wm in wlog:
+ self.assertEqual(wm.filename, '<unknown>')
+ self.assertIs(wm.category, SyntaxWarning)
+
 
 class CopyTests(unittest.TestCase):
  """Test copying and pickling AST nodes."""

Lib/test/test_builtin.py

@@ -1088,6 +1088,28 @@ def four_freevars():
  three_freevars.__globals__,
  closure=my_closure)
 
+ def test_exec_filter_syntax_warnings_by_module(self):
+ filename = support.findfile('test_import/data/syntax_warnings.py')
+ with open(filename, 'rb') as f:
+ source = f.read()
+ with warnings.catch_warnings(record=True) as wlog:
+ warnings.simplefilter('error')
+ warnings.filterwarnings('always', module=r'<string>\z')
+ exec(source, {})
+ self.assertEqual(sorted(wm.lineno for wm in wlog), [4, 7, 10, 13, 14, 21])
+ for wm in wlog:
+ self.assertEqual(wm.filename, '<string>')
+ self.assertIs(wm.category, SyntaxWarning)
+
+ with warnings.catch_warnings(record=True) as wlog:
+ warnings.simplefilter('error')
+ warnings.filterwarnings('always', module=r'<string>\z')
+ exec(source, {'__name__': 'package.module', '__file__': filename})
+ self.assertEqual(sorted(wm.lineno for wm in wlog), [4, 7, 10, 13, 14, 21])
+ for wm in wlog:
+ self.assertEqual(wm.filename, '<string>')
+ self.assertIs(wm.category, SyntaxWarning)
+
 
  def test_filter(self):
  self.assertEqual(list(filter(lambda c: 'a' <= c <= 'z', 'Hello World')), list('elloorld'))

Lib/test/test_cmd_line_script.py

@@ -810,6 +810,19 @@ def test_script_as_dev_fd(self):
  out, err = p.communicate()
  self.assertEqual(out, b"12345678912345678912345\n")
 
+ def test_filter_syntax_warnings_by_module(self):
+ filename = support.findfile('test_import/data/syntax_warnings.py')
+ rc, out, err = assert_python_ok(
+ '-Werror',
+ '-Walways:::test.test_import.data.syntax_warnings',
+ filename)
+ self.assertEqual(err.count(b': SyntaxWarning: '), 6)
+
+ rc, out, err = assert_python_ok(
+ '-Werror',
+ '-Walways:::syntax_warnings',
+ filename)
+ self.assertEqual(err.count(b': SyntaxWarning: '), 6)
 
 
 def tearDownModule():

Lib/test/test_compile.py

@@ -1745,6 +1745,20 @@ def test_compile_warning_in_finally(self):
  self.assertEqual(wm.category, SyntaxWarning)
  self.assertIn("\"is\" with 'int' literal", str(wm.message))
 
+ def test_filter_syntax_warnings_by_module(self):
+ filename = support.findfile('test_import/data/syntax_warnings.py')
+ with open(filename, 'rb') as f:
+ source = f.read()
+ module_re = r'test\.test_import\.data\.syntax_warnings\z'
+ with warnings.catch_warnings(record=True) as wlog:
+ warnings.simplefilter('error')
+ warnings.filterwarnings('always', module=module_re)
+ compile(source, filename, 'exec')
+ self.assertEqual(sorted(wm.lineno for wm in wlog), [4, 7, 10, 13, 14, 21])
+ for wm in wlog:
+ self.assertEqual(wm.filename, filename)
+ self.assertIs(wm.category, SyntaxWarning)
+
  @support.subTests('src', [
  textwrap.dedent("""
  def f():

Lib/test/test_import/__init__.py

@@ -15,6 +15,7 @@
 import os
 import py_compile
 import random
+import re
 import shutil
 import stat
 import subprocess
@@ -23,6 +24,7 @@
 import threading
 import time
 import types
+import warnings
 import unittest
 from unittest import mock
 import _imp
@@ -51,7 +53,7 @@
  TESTFN, rmtree, temp_umask, TESTFN_UNENCODABLE)
 from test.support import script_helper
 from test.support import threading_helper
-from test.test_importlib.util import uncache
+from test.test_importlib.util import uncache, temporary_pycache_prefix
 from types import ModuleType
 try:
  import _testsinglephase
@@ -412,7 +414,6 @@ def test_from_import_missing_attr_path_is_canonical(self):
  self.assertIsNotNone(cm.exception)
 
  def test_from_import_star_invalid_type(self):
- import re
  with ready_to_import() as (name, path):
  with open(path, 'w', encoding='utf-8') as f:
  f.write("__all__ = [b'invalid_type']")
@@ -1250,6 +1251,35 @@ class Spec2:
  origin = "a\x00b"
  _imp.create_dynamic(Spec2())
 
+ def test_filter_syntax_warnings_by_module(self):
+ module_re = r'test\.test_import\.data\.syntax_warnings\z'
+ unload('test.test_import.data.syntax_warnings')
+ with (os_helper.temp_dir() as tmpdir,
+ temporary_pycache_prefix(tmpdir),
+ warnings.catch_warnings(record=True) as wlog):
+ warnings.simplefilter('error')
+ warnings.filterwarnings('always', module=module_re)
+ import test.test_import.data.syntax_warnings
+ self.assertEqual(sorted(wm.lineno for wm in wlog), [4, 7, 10, 13, 14, 21])
+ filename = test.test_import.data.syntax_warnings.__file__
+ for wm in wlog:
+ self.assertEqual(wm.filename, filename)
+ self.assertIs(wm.category, SyntaxWarning)
+
+ module_re = r'syntax_warnings\z'
+ unload('test.test_import.data.syntax_warnings')
+ with (os_helper.temp_dir() as tmpdir,
+ temporary_pycache_prefix(tmpdir),
+ warnings.catch_warnings(record=True) as wlog):
+ warnings.simplefilter('error')
+ warnings.filterwarnings('always', module=module_re)
+ import test.test_import.data.syntax_warnings
+ self.assertEqual(sorted(wm.lineno for wm in wlog), [4, 7, 10, 13, 14, 21])
+ filename = test.test_import.data.syntax_warnings.__file__
+ for wm in wlog:
+ self.assertEqual(wm.filename, filename)
+ self.assertIs(wm.category, SyntaxWarning)
+
 
 @skip_if_dont_write_bytecode
 class FilePermissionTests(unittest.TestCase):

Lib/test/test_import/data/syntax_warnings.py

@@ -0,0 +1,21 @@
+# Syntax warnings emitted in different parts of the Python compiler.
+
+# Parser/lexer/lexer.c
+x = 1or 0 # line 4
+
+# Parser/tokenizer/helpers.c
+'\z' # line 7
+
+# Parser/string_parser.c
+'\400' # line 10
+
+# _PyCompile_Warn() in Python/codegen.c
+assert(x, 'message') # line 13
+x is 1 # line 14
+
+# _PyErr_EmitSyntaxWarning() in Python/ast_preprocess.c
+def f():
+ try:
+ pass
+ finally:
+ return 42 # line 21

Lib/test/test_symtable.py

@@ -5,6 +5,7 @@
 import re
 import textwrap
 import symtable
+import warnings
 import unittest
 
 from test import support
@@ -586,6 +587,20 @@ def test__symtable_refleak(self):
  # check error path when 'compile_type' AC conversion failed
  self.assertRaises(TypeError, symtable.symtable, '', mortal_str, 1)
 
+ def test_filter_syntax_warnings_by_module(self):
+ filename = support.findfile('test_import/data/syntax_warnings.py')
+ with open(filename, 'rb') as f:
+ source = f.read()
+ module_re = r'test\.test_import\.data\.syntax_warnings\z'
+ with warnings.catch_warnings(record=True) as wlog:
+ warnings.simplefilter('error')
+ warnings.filterwarnings('always', module=module_re)
+ symtable.symtable(source, filename, 'exec')
+ self.assertEqual(sorted(wm.lineno for wm in wlog), [4, 7, 10])
+ for wm in wlog:
+ self.assertEqual(wm.filename, filename)
+ self.assertIs(wm.category, SyntaxWarning)
+
 
 class ComprehensionTests(unittest.TestCase):
  def get_identifiers_recursive(self, st, res):

Lib/test/test_warnings/__init__.py

@@ -249,10 +249,23 @@ def test_filter_module(self):
  self.module.warn_explicit('msg', UserWarning, 'filename', 42,
  module='package.module')
  self.assertEqual(len(w), 1)
+ self.module.warn_explicit('msg', UserWarning, '/path/to/package/module', 42)
+ self.assertEqual(len(w), 2)
+ self.module.warn_explicit('msg', UserWarning, '/path/to/package/module.py', 42)
+ self.assertEqual(len(w), 3)
+ self.module.warn_explicit('msg', UserWarning, '/path/to/package/module/__init__.py', 42)
+ self.assertEqual(len(w), 4)
  with self.assertRaises(UserWarning):
- self.module.warn_explicit('msg', UserWarning, '/path/to/package/module', 42)
- with self.assertRaises(UserWarning):
- self.module.warn_explicit('msg', UserWarning, '/path/to/package/module.py', 42)
+ self.module.warn_explicit('msg', UserWarning, '/path/to/package/module/__init__', 42)
+ if MS_WINDOWS:
+ self.module.warn_explicit('msg', UserWarning, r'C:\path\to\package\module.PY', 42)
+ self.assertEqual(len(w), 5)
+ self.module.warn_explicit('msg', UserWarning, r'C:\path\to\package\module\__INIT__.PY', 42)
+ self.assertEqual(len(w), 6)
+ self.module.warn_explicit('msg', UserWarning, r'C:\path\to\package\module.PYW', 42)
+ self.assertEqual(len(w), 7)
+ self.module.warn_explicit('msg', UserWarning, r'C:\path\to\package\module\__INIT__.PYW', 42)
+ self.assertEqual(len(w), 8)
 
  with self.module.catch_warnings(record=True) as w:
  self.module.simplefilter('error')
@@ -276,9 +289,8 @@ def test_filter_module(self):
  with self.assertRaises(UserWarning):
  self.module.warn_explicit('msg', UserWarning, '/PATH/TO/PACKAGE/MODULE', 42)
  if MS_WINDOWS:
- if self.module is py_warnings:
- self.module.warn_explicit('msg', UserWarning, r'/path/to/package/module.PY', 42)
- self.assertEqual(len(w), 3)
+ self.module.warn_explicit('msg', UserWarning, r'/path/to/package/module.PY', 42)
+ self.assertEqual(len(w), 3)
  with self.assertRaises(UserWarning):
  self.module.warn_explicit('msg', UserWarning, r'/path/to/package/module/__init__.py', 42)
  with self.assertRaises(UserWarning):
@@ -302,9 +314,8 @@ def test_filter_module(self):
  self.assertEqual(len(w), 1)
  self.module.warn_explicit('msg', UserWarning, r'C:\path\to\package\module.py', 42)
  self.assertEqual(len(w), 2)
- if self.module is py_warnings:
- self.module.warn_explicit('msg', UserWarning, r'C:\path\to\package\module.PY', 42)
- self.assertEqual(len(w), 3)
+ self.module.warn_explicit('msg', UserWarning, r'C:\path\to\package\module.PY', 42)
+ self.assertEqual(len(w), 3)
  with self.assertRaises(UserWarning):
  self.module.warn_explicit('msg', UserWarning, r'C:\path\to\package\module.pyw', 42)
  with self.assertRaises(UserWarning):
@@ -399,7 +410,7 @@ def test_message_matching(self):
 
  def test_mutate_filter_list(self):
  class X:
- def match(self, a):
+ def match(self, a, start=0):
  L[:] = []
 
  L = [("default",X(),UserWarning,X(),0) for i in range(2)]