Fixed a bug where patcher was leaving crap in sys.modules, added a unit test that is huuuge but works correctly.

eventlet/patcher.py

@@ -33,6 +33,8 @@ def inject(module_name, new_globals, *additional_modules):
     for name, mod in additional_modules:
         if saved[name] is not None:
             sys.modules[name] = saved[name]
+        else:
+            del sys.modules[name]
 
     return module
 

tests/patcher_test.py

@@ -0,0 +1,72 @@
+import os
+import tempfile
+import subprocess
+import sys
+
+from tests import LimitedTestCase
+
+base_module_contents = """
+import socket
+import urllib
+print "base", socket, urllib
+"""
+
+patching_module_contents = """
+from eventlet.green import socket
+from eventlet.green import urllib
+from eventlet import patcher
+print 'patcher', socket, urllib
+patcher.inject('%s', globals(), ('socket', socket), ('urllib', urllib))
+del patcher
+"""
+
+import_module_contents = """
+import %(mod)s
+import httplib
+print "importing", %(mod)s, httplib, %(mod)s.socket, %(mod)s.urllib
+"""
+
+class Patcher(LimitedTestCase):
+    TEST_TIMEOUT=3 # starting processes is time-consuming
+    def setUp(self):
+        self._saved_syspath = sys.path
+        self.tempfiles = []
+        
+    def tearDown(self):
+        sys.path = self._saved_syspath
+        for tf in self.tempfiles:
+            os.remove(tf)
+        
+    def write_to_tempfile(self, contents):
+        fn, filename = tempfile.mkstemp('_patcher_test.py')
+        fd = os.fdopen(fn, 'w')
+        fd.write(contents)
+        fd.close()
+        self.tempfiles.append(filename)
+        return os.path.dirname(filename), os.path.basename(filename)
+
+    def test_patch_a_module(self):
+        base = self.write_to_tempfile(base_module_contents)
+        base_modname = os.path.splitext(base[1])[0]
+        patching = self.write_to_tempfile(patching_module_contents % base_modname)
+        patching_modname = os.path.splitext(patching[1])[0]
+        importing = self.write_to_tempfile(
+            import_module_contents % dict(mod=patching_modname))
+        
+        python_path = os.pathsep.join(sys.path)
+        python_path += os.pathsep.join((base[0], patching[0], importing[0]))
+        new_env = os.environ.copy()
+        new_env['PYTHONPATH'] = python_path
+        p = subprocess.Popen([sys.executable, 
+                    os.path.join(importing[0], importing[1])],
+                stdout=subprocess.PIPE, env=new_env)
+        output = p.communicate()
+        lines = output[0].split("\n")
+        self.assert_(lines[0].startswith('patcher'))
+        self.assert_(lines[1].startswith('base'))
+        self.assert_(lines[2].startswith('importing'))
+        self.assert_('eventlet.green.socket' in lines[1])
+        self.assert_('eventlet.green.urllib' in lines[1])
+        self.assert_('eventlet.green.socket' in lines[2])
+        self.assert_('eventlet.green.urllib' in lines[2])
+        self.assert_('eventlet.green.httplib' not in lines[2])