bpo-33375: Get filename for warnings from frame.f_code.co_filename (GH-6622)

More consistent with how other parts of Python find the filename (e.g. tracebacks and pdb).

2 files changed, 11 insertions, 89 deletions

diff --git a/Lib/test/test_warnings/__init__.py b/Lib/test/test_warnings/__init__.py
index b48debd..71f6a30 100644
--- a/Lib/test/test_warnings/__init__.py
+++ b/Lib/test/test_warnings/__init__.py
@@ -441,78 +441,14 @@ class WarnTests(BaseTest):
                 self.assertEqual(len(w), 1)
                 self.assertEqual(w[0].filename, __file__)
 
-    def test_missing_filename_not_main(self):
-        # If __file__ is not specified and __main__ is not the module name,
-        # then __file__ should be set to the module name.
-        filename = warning_tests.__file__
-        try:
-            del warning_tests.__file__
-            with warnings_state(self.module):
-                with original_warnings.catch_warnings(record=True,
-                        module=self.module) as w:
-                    warning_tests.inner("spam8", stacklevel=1)
-                    self.assertEqual(w[-1].filename, warning_tests.__name__)
-        finally:
-            warning_tests.__file__ = filename
-
-    @unittest.skipUnless(hasattr(sys, 'argv'), 'test needs sys.argv')
-    def test_missing_filename_main_with_argv(self):
-        # If __file__ is not specified and the caller is __main__ and sys.argv
-        # exists, then use sys.argv[0] as the file.
-        filename = warning_tests.__file__
-        module_name = warning_tests.__name__
-        try:
-            del warning_tests.__file__
-            warning_tests.__name__ = '__main__'
-            with warnings_state(self.module):
-                with original_warnings.catch_warnings(record=True,
-                        module=self.module) as w:
-                    warning_tests.inner('spam9', stacklevel=1)
-                    self.assertEqual(w[-1].filename, sys.argv[0])
-        finally:
-            warning_tests.__file__ = filename
-            warning_tests.__name__ = module_name
-
-    def test_missing_filename_main_without_argv(self):
-        # If __file__ is not specified, the caller is __main__, and sys.argv
-        # is not set, then '__main__' is the file name.
-        filename = warning_tests.__file__
-        module_name = warning_tests.__name__
-        argv = sys.argv
-        try:
-            del warning_tests.__file__
-            warning_tests.__name__ = '__main__'
-            del sys.argv
-            with warnings_state(self.module):
-                with original_warnings.catch_warnings(record=True,
-                        module=self.module) as w:
-                    warning_tests.inner('spam10', stacklevel=1)
-                    self.assertEqual(w[-1].filename, '__main__')
-        finally:
-            warning_tests.__file__ = filename
-            warning_tests.__name__ = module_name
-            sys.argv = argv
-
-    def test_missing_filename_main_with_argv_empty_string(self):
-        # If __file__ is not specified, the caller is __main__, and sys.argv[0]
-        # is the empty string, then '__main__ is the file name.
-        # Tests issue 2743.
-        file_name = warning_tests.__file__
-        module_name = warning_tests.__name__
-        argv = sys.argv
-        try:
-            del warning_tests.__file__
-            warning_tests.__name__ = '__main__'
-            sys.argv = ['']
-            with warnings_state(self.module):
-                with original_warnings.catch_warnings(record=True,
-                        module=self.module) as w:
-                    warning_tests.inner('spam11', stacklevel=1)
-                    self.assertEqual(w[-1].filename, '__main__')
-        finally:
-            warning_tests.__file__ = file_name
-            warning_tests.__name__ = module_name
-            sys.argv = argv
+    def test_exec_filename(self):
+        filename = "<warnings-test>"
+        codeobj = compile(("import warnings\n"
+                           "warnings.warn('hello', UserWarning)"),
+                          filename, "exec")
+        with original_warnings.catch_warnings(record=True) as w:
+            exec(codeobj)
+        self.assertEqual(w[0].filename, filename)
 
     def test_warn_explicit_non_ascii_filename(self):
         with original_warnings.catch_warnings(record=True,
@@ -1245,9 +1181,7 @@ class A:
 a=A()
         """
         rc, out, err = assert_python_ok("-c", code)
-        # note: "__main__" filename is not correct, it should be the name
-        # of the script
-        self.assertEqual(err.decode(), '__main__:7: UserWarning: test')
+        self.assertEqual(err.decode(), '<string>:7: UserWarning: test')
 
     def test_late_resource_warning(self):
         # Issue #21925: Emitting a ResourceWarning late during the Python
diff --git a/Lib/warnings.py b/Lib/warnings.py
index 81f9864..6830b60 100644
--- a/Lib/warnings.py
+++ b/Lib/warnings.py
@@ -303,28 +303,16 @@ def warn(message, category=None, stacklevel=1, source=None):
                     raise ValueError
     except ValueError:
         globals = sys.__dict__
+        filename = "sys"
         lineno = 1
     else:
         globals = frame.f_globals
+        filename = frame.f_code.co_filename
         lineno = frame.f_lineno
     if '__name__' in globals:
         module = globals['__name__']
     else:
         module = "<string>"
-    filename = globals.get('__file__')
-    if filename:
-        fnl = filename.lower()
-        if fnl.endswith(".pyc"):
-            filename = filename[:-1]
-    else:
-        if module == "__main__":
-            try:
-                filename = sys.argv[0]
-            except AttributeError:
-                # embedded interpreters don't have sys.argv, see bug #839151
-                filename = '__main__'
-        if not filename:
-            filename = module
     registry = globals.setdefault("__warningregistry__", {})
     warn_explicit(message, category, filename, lineno, module, registry,
                   globals, source)