python
diff --git a/‎Include/pythonrun.h‎
Lines changed: 1 addition & 0 deletions b/‎Include/pythonrun.h‎
Lines changed: 1 addition & 0 deletions
diff --git a/‎Lib/site.py‎
Lines changed: 4 additions & 9 deletions b/‎Lib/site.py‎
Lines changed: 4 additions & 9 deletions
diff --git a/‎Lib/test/test_importhooks.py‎
Lines changed: 204 additions & 0 deletions b/‎Lib/test/test_importhooks.py‎
Lines changed: 204 additions & 0 deletions
@@ -99,6 +99,7 @@ PyAPI_FUNC(PyObject *) _PyBuiltin_Init(void);
 PyAPI_FUNC(PyObject *) _PySys_Init(void);
 PyAPI_FUNC(void) _PyImport_Init(void);
 PyAPI_FUNC(void) _PyExc_Init(void);
+PyAPI_FUNC(void) _PyImportHooks_Init(void);
 
 /* Various internal finalizers */
 PyAPI_FUNC(void) _PyExc_Fini(void);
 
@@ -73,16 +73,11 @@ def makepath(*paths):
 # only absolute pathnames, even if we're running from the build directory.
 L = []
 _dirs_in_sys_path = {}
+dir = dircase = None  # sys.path may be empty at this point
 for dir in sys.path:
-    # Filter out paths that don't exist, but leave in the empty string
-    # since it's a special case. We also need to special-case the Mac,
-    # as file names are allowed on sys.path there.
-    if sys.platform != 'mac':
-        if dir and not os.path.isdir(dir):
-            continue
-    else:
-        if dir and not os.path.exists(dir):
-            continue
+    # Filter out duplicate paths (on case-insensitive file systems also
+    # if they only differ in case); turn relative paths into absolute
+    # paths.
     dir, dircase = makepath(dir)
     if not dircase in _dirs_in_sys_path:
         L.append(dir)
 
@@ -0,0 +1,204 @@
+import sys
+import imp
+import os
+import unittest
+from test import test_support
+
+
+test_src = """\
+def get_name():
+    return __name__
+def get_file():
+    return __file__
+"""
+
+test_co = compile(test_src, "<???>", "exec")
+test_path = "!!!_test_!!!"
+
+
+class ImportTracker:
+    """Importer that only tracks attempted imports."""
+    def __init__(self):
+        self.imports = []
+    def find_module(self, fullname, path=None):
+        self.imports.append(fullname)
+        return None
+
+
+class TestImporter:
+
+    modules = {
+        "hooktestmodule": (False, test_co),
+        "hooktestpackage": (True, test_co),
+        "hooktestpackage.sub": (True, test_co),
+        "hooktestpackage.sub.subber": (False, test_co),
+    }
+
+    def __init__(self, path=test_path):
+        if path != test_path:
+            # if out class is on sys.path_hooks, we must raise
+            # ImportError for any path item that we can't handle.
+            raise ImportError
+        self.path = path
+
+    def _get__path__(self):
+        raise NotImplementedError
+
+    def find_module(self, fullname, path=None):
+        if fullname in self.modules:
+            return self
+        else:
+            return None
+
+    def load_module(self, fullname):
+        ispkg, code = self.modules[fullname]
+        mod = imp.new_module(fullname)
+        sys.modules[fullname] = mod
+        mod.__file__ = "<%s>" % self.__class__.__name__
+        mod.__loader__ = self
+        if ispkg:
+            mod.__path__ = self._get__path__()
+        exec code in mod.__dict__
+        return mod
+
+
+class MetaImporter(TestImporter):
+    def _get__path__(self):
+        return []
+
+class PathImporter(TestImporter):
+    def _get__path__(self):
+        return [self.path]
+
+
+class ImportBlocker:
+    """Place an ImportBlocker instance on sys.meta_path and you
+    can be sure the modules you specified can't be imported, even
+    if it's a builtin."""
+    def __init__(self, *namestoblock):
+        self.namestoblock = dict.fromkeys(namestoblock)
+    def find_module(self, fullname, path=None):
+        if fullname in self.namestoblock:
+            return self
+        return None
+    def load_module(self, fullname):
+        raise ImportError, "I dare you"
+
+
+class ImpWrapper:
+
+    def __init__(self, path=None):
+        if path is not None and not os.path.isdir(path):
+            raise ImportError
+        self.path = path
+
+    def find_module(self, fullname, path=None):
+        subname = fullname.split(".")[-1]
+        if subname != fullname and self.path is None:
+            return None
+        if self.path is None:
+            path = None
+        else:
+            path = [self.path]
+        try:
+            file, filename, stuff = imp.find_module(subname, path)
+        except ImportError:
+            return None
+        return ImpLoader(file, filename, stuff)
+
+
+class ImpLoader:
+
+    def __init__(self, file, filename, stuff):
+        self.file = file
+        self.filename = filename
+        self.stuff = stuff
+
+    def load_module(self, fullname):
+        mod = imp.load_module(fullname, self.file, self.filename, self.stuff)
+        if self.file:
+            self.file.close()
+        mod.__loader__ = self  # for introspection
+        return mod
+
+
+class ImportHooksBaseTestCase(unittest.TestCase):
+
+    def setUp(self):
+        self.path = sys.path[:]
+        self.meta_path = sys.meta_path[:]
+        self.path_hooks = sys.path_hooks[:]
+        sys.path_importer_cache.clear()
+        self.tracker = ImportTracker()
+        sys.meta_path.insert(0, self.tracker)
+
+    def tearDown(self):
+        sys.path[:] = self.path
+        sys.meta_path[:] = self.meta_path
+        sys.path_hooks[:] = self.path_hooks
+        sys.path_importer_cache.clear()
+        for fullname in self.tracker.imports:
+            if fullname in sys.modules:
+                del sys.modules[fullname]
+
+
+class ImportHooksTestCase(ImportHooksBaseTestCase):
+
+    def doTestImports(self, importer=None):
+        import hooktestmodule
+        import hooktestpackage
+        import hooktestpackage.sub
+        import hooktestpackage.sub.subber
+        self.assertEqual(hooktestmodule.get_name(),
+                         "hooktestmodule")
+        self.assertEqual(hooktestpackage.get_name(),
+                         "hooktestpackage")
+        self.assertEqual(hooktestpackage.sub.get_name(),
+                         "hooktestpackage.sub")
+        self.assertEqual(hooktestpackage.sub.subber.get_name(),
+                         "hooktestpackage.sub.subber")
+        if importer:
+            self.assertEqual(hooktestmodule.__loader__, importer)
+            self.assertEqual(hooktestpackage.__loader__, importer)
+            self.assertEqual(hooktestpackage.sub.__loader__, importer)
+            self.assertEqual(hooktestpackage.sub.subber.__loader__, importer)
+
+    def testMetaPath(self):
+        i = MetaImporter()
+        sys.meta_path.append(i)
+        self.doTestImports(i)
+
+    def testPathHook(self):
+        sys.path_hooks.append(PathImporter)
+        sys.path.append(test_path)
+        self.doTestImports()
+
+    def testBlocker(self):
+        mname = "exceptions"  # an arbitrary harmless builtin module
+        if mname in sys.modules:
+            del sys.modules[mname]
+        sys.meta_path.append(ImportBlocker(mname))
+        try:
+            __import__(mname)
+        except ImportError:
+            pass
+        else:
+            self.fail("'%s' was not supposed to be importable" % mname)
+
+    def testImpWrapper(self):
+        i = ImpWrapper()
+        sys.meta_path.append(i)
+        sys.path_hooks.append(ImpWrapper)
+        mnames = ("colorsys", "urlparse", "distutils.core", "compiler.misc")
+        for mname in mnames:
+            parent = mname.split(".")[0]
+            for n in sys.modules.keys():
+                if n.startswith(parent):
+                    del sys.modules[n]
+        for mname in mnames:
+            m = __import__(mname, globals(), locals(), ["__dummy__"])
+            m.__loader__  # to make sure we actually handled the import
+
+
+if __name__ == "__main__":
+    test_support.run_unittest(ImportHooksTestCase)