Issue 4195: Restore the ability to execute packages with the -m switch (but this time in a way that leaves the import machinery in a valid state). (Original patch by Andi Vajda)

2 files changed, 75 insertions, 6 deletions

diff --git a/Lib/runpy.py b/Lib/runpy.py
index fea6104..f9a29ad 100755
--- a/Lib/runpy.py
+++ b/Lib/runpy.py
@@ -80,13 +80,19 @@ def _get_module_details(mod_name):
     if loader is None:
         raise ImportError("No module named %s" % mod_name)
     if loader.is_package(mod_name):
-        raise ImportError(("%s is a package and cannot " +
-                          "be directly executed") % mod_name)
+        if mod_name == "__main__" or mod_name.endswith(".__main__"):
+            raise ImportError(("Cannot use package as __main__ module"))
+        try:
+            pkg_main_name = mod_name + ".__main__"
+            return _get_module_details(pkg_main_name)
+        except ImportError, e:
+            raise ImportError(("%s; %r is a package and cannot " +
+                               "be directly executed") %(e, mod_name))
     code = loader.get_code(mod_name)
     if code is None:
         raise ImportError("No code object available for %s" % mod_name)
     filename = _get_filename(loader, mod_name)
-    return loader, code, filename
+    return mod_name, loader, code, filename
 
 
 # XXX ncoghlan: Should this be documented and made public?
@@ -101,12 +107,12 @@ def _run_module_as_main(mod_name, set_argv0=True):
            __loader__
     """
     try:
-        loader, code, fname = _get_module_details(mod_name)
+        mod_name, loader, code, fname = _get_module_details(mod_name)
     except ImportError as exc:
         # Try to provide a good error message
         # for directories, zip files and the -m switch
         if set_argv0:
-            # For -m switch, just disply the exception
+            # For -m switch, just display the exception
             info = str(exc)
         else:
             # For directories/zipfiles, let the user
@@ -127,7 +133,7 @@ def run_module(mod_name, init_globals=None,
 
        Returns the resulting top level namespace dictionary
     """
-    loader, code, fname = _get_module_details(mod_name)
+    mod_name, loader, code, fname = _get_module_details(mod_name)
     if run_name is None:
         run_name = mod_name
     pkg_name = mod_name.rpartition('.')[0]
diff --git a/Lib/test/test_cmd_line_script.py b/Lib/test/test_cmd_line_script.py
index 995d4a8..29c92fa 100644
--- a/Lib/test/test_cmd_line_script.py
+++ b/Lib/test/test_cmd_line_script.py
@@ -158,6 +158,16 @@ class CmdLineTest(unittest.TestCase):
         self.assert_(printed_package in data)
         self.assert_(printed_argv0 in data)
 
+    def _check_import_error(self, script_name, expected_msg,
+                            *cmd_line_switches):
+        run_args = cmd_line_switches + (script_name,)
+        exit_code, data = _run_python(*run_args)
+        if verbose:
+            print 'Output from test script %r:' % script_name
+            print data
+            print 'Expected output: %r' % expected_msg
+        self.assert_(expected_msg in data)
+
     def test_basic_script(self):
         with temp_dir() as script_dir:
             script_name = _make_test_script(script_dir, 'script')
@@ -182,6 +192,11 @@ class CmdLineTest(unittest.TestCase):
             os.remove(script_name)
             self._check_script(script_dir, compiled_name, script_dir, '')
 
+    def test_directory_error(self):
+        with temp_dir() as script_dir:
+            msg = "can't find '__main__.py' in %r" % script_dir
+            self._check_import_error(script_dir, msg)
+
     def test_zipfile(self):
         with temp_dir() as script_dir:
             script_name = _make_test_script(script_dir, '__main__')
@@ -195,6 +210,13 @@ class CmdLineTest(unittest.TestCase):
             zip_name, run_name = _make_test_zip(script_dir, 'test_zip', compiled_name)
             self._check_script(zip_name, run_name, zip_name, '')
 
+    def test_zipfile_error(self):
+        with temp_dir() as script_dir:
+            script_name = _make_test_script(script_dir, 'not_main')
+            zip_name, run_name = _make_test_zip(script_dir, 'test_zip', script_name)
+            msg = "can't find '__main__.py' in %r" % zip_name
+            self._check_import_error(zip_name, msg)
+
     def test_module_in_package(self):
         with temp_dir() as script_dir:
             pkg_dir = os.path.join(script_dir, 'test_pkg')
@@ -215,6 +237,47 @@ class CmdLineTest(unittest.TestCase):
             launch_name = _make_launch_script(script_dir, 'launch', 'test_pkg.test_pkg.script', zip_name)
             self._check_script(launch_name, run_name, run_name, 'test_pkg.test_pkg')
 
+    def test_package(self):
+        with temp_dir() as script_dir:
+            pkg_dir = os.path.join(script_dir, 'test_pkg')
+            _make_test_pkg(pkg_dir)
+            script_name = _make_test_script(pkg_dir, '__main__')
+            launch_name = _make_launch_script(script_dir, 'launch', 'test_pkg')
+            self._check_script(launch_name, script_name,
+                               script_name, 'test_pkg')
+
+    def test_package_compiled(self):
+        with temp_dir() as script_dir:
+            pkg_dir = os.path.join(script_dir, 'test_pkg')
+            _make_test_pkg(pkg_dir)
+            script_name = _make_test_script(pkg_dir, '__main__')
+            compiled_name = _compile_test_script(script_name)
+            os.remove(script_name)
+            launch_name = _make_launch_script(script_dir, 'launch', 'test_pkg')
+            self._check_script(launch_name, compiled_name,
+                               compiled_name, 'test_pkg')
+
+    def test_package_error(self):
+        with temp_dir() as script_dir:
+            pkg_dir = os.path.join(script_dir, 'test_pkg')
+            _make_test_pkg(pkg_dir)
+            msg = ("'test_pkg' is a package and cannot "
+                   "be directly executed")
+            launch_name = _make_launch_script(script_dir, 'launch', 'test_pkg')
+            self._check_import_error(launch_name, msg)
+
+    def test_package_recursion(self):
+        with temp_dir() as script_dir:
+            pkg_dir = os.path.join(script_dir, 'test_pkg')
+            _make_test_pkg(pkg_dir)
+            main_dir = os.path.join(pkg_dir, '__main__')
+            _make_test_pkg(main_dir)
+            msg = ("Cannot use package as __main__ module; "
+                   "'test_pkg' is a package and cannot "
+                   "be directly executed")
+            launch_name = _make_launch_script(script_dir, 'launch', 'test_pkg')
+            self._check_import_error(launch_name, msg)
+
 
 def test_main():
     test.test_support.run_unittest(CmdLineTest)