Use runpy.run_path for 'python -m gevent.monkey'.

This lets us run packages and compiled files, as well as automatically taking care of all the import related globals like __file__ and __package__.

Fixes #1157

CHANGES.rst

@@ -60,6 +60,10 @@ Enhancements
   time-sensitive parts of the hub itself. Please report any
   compatibility issues.
 
+- ``python -m gevent.monkey <script>`` accepts more values for
+  ``<script>``, including paths to packages or compiled bytecode.
+  Reported in :issue:`1157` by Eddie Linder.
+
 Monitoring and Debugging
 ------------------------
 

src/gevent/monkey.py

@@ -766,13 +766,13 @@ def main():
     patch_all(**args)
     if argv:
         sys.argv = argv
-        __package__ = None
-        assert __package__ is None
-        globals()['__file__'] = sys.argv[0]  # issue #302
-        globals()['__package__'] = None # issue #975: make script be its own package
-        with open(sys.argv[0]) as f:
-            # Be sure to exec in globals to avoid import pollution. Also #975.
-            exec(f.read(), globals())
+        import runpy
+        # Use runpy.run_path to closely (exactly) match what the
+        # interpreter does given 'python <path>'. This includes allowing
+        # passing .pyc/.pyo files and packages with a __main__ and
+        # potentially even zip files. Previously we used exec, which only
+        # worked if we directly read a python source file.
+        runpy.run_path(sys.argv[0], run_name='__main__')
     else:
         print(script_help)
 
@@ -795,6 +795,12 @@ You can exclude a module with --no-module, e.g. --no-thread. You can
 specify a module to patch with --module, e.g. --socket. In the latter
 case only the modules specified on the command line will be patched.
 
+.. versionchanged:: 1.3b1
+    The *script* argument can now be any argument that can be passed to `runpy.run_path`,
+    just like the interpreter itself does, for example a package directory containing ``__main__.py``.
+    Previously it had to be the path to
+    a .py source file.
+
 MONKEY OPTIONS: --verbose %s""" % ', '.join('--[no-]%s' % m for m in modules)
     return script_help, patch_all_args, modules
 

src/greentest/monkey_package/__main__.py

+from __future__ import print_function
+# This file makes this directory into a package.
+# it exists to test 'python -m gevent.monkey monkey_package'
+print(__file__)
+print(__name__)

src/greentest/test__monkey_scope.py

@@ -3,11 +3,24 @@ import sys
 
 if 'gevent' not in sys.modules:
     from subprocess import Popen
+    from subprocess import PIPE
+    # Run a simple script
     args = [sys.executable, '-m', 'gevent.monkey', __file__]
     p = Popen(args)
     code = p.wait()
     assert code == 0, code
 
+    # Run a __main__ inside a package.
+    args = [sys.executable, '-m', 'gevent.monkey', 'monkey_package']
+    p = Popen(args, stdout=PIPE, stderr=PIPE)
+    out, err = p.communicate()
+    lines = out.splitlines()
+    assert lines[0].endswith(b'__main__.py'), (out, err)
+    assert lines[1] == b'__main__', (lines, out, err)
+    # Python 3.7 tends to produce some inscrutable
+    # warning from importlib._bootstrap.py on stderr
+    # "ImportWarning: can't resolve package from __spec__ or __package__".
+    # So we don't check that err is empty.
 else:
     from textwrap import dedent