raise ResourceInvalidError when open() is called on a directory

fs/memoryfs.py

@@ -340,6 +340,8 @@ class MemoryFS(FS):
                 raise ResourceNotFoundError(path)
 
             file_dir_entry = parent_dir_entry.contents[filename]
+            if file_dir_entry.isdir():
+                raise ResourceInvalidError(path)
 
             if 'a' in mode:
                 if file_dir_entry.islocked():
@@ -567,4 +569,4 @@ class MemoryFS(FS):
     @synchronize
     def listxattrs(self, path):
         dir_entry = self._dir_entry(path)
-        return dir_entry.xattrs.keys()
+        return dir_entry.xattrs.keys()
\ No newline at end of file

fs/osfs/__init__.py

@@ -149,7 +149,14 @@ class OSFS(OSFSXAttrMixin, OSFSWatchMixin, FS):
     @convert_os_errors
     def open(self, path, mode="r", **kwargs):
         mode = filter(lambda c: c in "rwabt+",mode)
-        return open(self.getsyspath(path), mode, kwargs.get("buffering", -1))
+        sys_path = self.getsyspath(path)
+        try:
+            return open(sys_path, mode, kwargs.get("buffering", -1))
+        except EnvironmentError, e:
+            #  Win32 gives EACCES when opening a directory.
+            if sys.platform == "win32" and e.errno in (errno.EACCES,):
+                raise ResourceInvalidError(path)
+            raise
 
     @convert_os_errors
     def exists(self, path):
@@ -246,7 +253,7 @@ class OSFS(OSFSXAttrMixin, OSFSWatchMixin, FS):
                 #  a directory that doesn't exist.  We want ParentMissingError
                 #  in this case.
                 if e.errno == errno.ENOENT:
-                    if not os.path.exists(dirname(path_dst)):
+                    if not os.path.exists(os.path.dirname(path_dst)):
                         raise ParentDirectoryMissingError(dst)
             raise            
         

fs/tests/__init__.py

@@ -68,6 +68,10 @@ class FSTestCases(object):
         repr(self.fs)
         self.assert_(hasattr(self.fs, 'desc'))
 
+    def test_open_on_directory(self):
+        self.fs.makedir("testdir")
+        self.assertRaises(ResourceInvalidError,self.fs.open,"testdir")
+      
     def test_writefile(self):
         self.assertRaises(ResourceNotFoundError,self.fs.open,"test1.txt")
         f = self.fs.open("test1.txt","w")