Add file permissions to filesystem_mock

third_party/WebKit/Tools/Scripts/webkitpy/common/system/filesystem_mock.py

Index: third_party/WebKit/Tools/Scripts/webkitpy/common/system/filesystem_mock.py
diff --git a/third_party/WebKit/Tools/Scripts/webkitpy/common/system/filesystem_mock.py b/third_party/WebKit/Tools/Scripts/webkitpy/common/system/filesystem_mock.py
index 44c7d8043d507f9dad2c683232b2e28ea01e5dd7..00eb93503463ec29a9f50ca2eb4bf1ccf13857e8 100644
--- a/third_party/WebKit/Tools/Scripts/webkitpy/common/system/filesystem_mock.py
+++ b/third_party/WebKit/Tools/Scripts/webkitpy/common/system/filesystem_mock.py
@@ -39,7 +39,7 @@ class MockFileSystem(object):
     sep = '/'
     pardir = '..'
 
-    def __init__(self, files=None, dirs=None, cwd='/'):
+    def __init__(self, files=None, dirs=None, cwd='/', permissions=None):
         """Initializes a "mock" filesystem that can be used to completely
         stub out a filesystem.
 
@@ -49,6 +49,7 @@ class MockFileSystem(object):
                 not exist.
         """
         self.files = files or {}
+        self.permissions = permissions or {}
         self.written_files = {}
         self.last_tmpdir = None
         self.current_tmpno = 0
@@ -56,11 +57,13 @@ class MockFileSystem(object):
         self.dirs = set(dirs or [])
         self.dirs.add(cwd)
         for f in self.files:
+            while f not in self.permissions:
+                self.permissions[f] = False
+        for f in self.files:

[qyearsley, 2016/06/15 21:54:25]

Depending on how is_executable is implemented, this may be unnecessary.

For example, if is_executable is:

    def is_executable(self, path):
        return self.permissions.get(path, False)

In this case, self.permissions is just a dict of paths to True for all paths
where the file is executable -- which behaves just the same as a set. In Python,
sets are also a basic type (like lists, tuples and dicts), so you could also do
this:

    def __init__(...):
        ...
        self.executable_files = set()
        ...

    def is_executable(path):
        return path in self.executable_files

             d = self.dirname(f)
             while not d in self.dirs:
                 self.dirs.add(d)
                 d = self.dirname(d)
-
     def clear_written_files(self):
         # This function can be used to track what is written between steps in a test.
         self.written_files = {}
@@ -75,6 +78,11 @@ class MockFileSystem(object):
             return path.rsplit(self.sep, 1)
         return ('', path)
 
+    def chmod(self, file_path, mode):

[qyearsley, 2016/06/15 21:54:25]

In the MockFileSystem class, we still want to have is_exectuable and
make_executable (and not chmod), since the API of the mock class should look
just like that of the real class.

+        # To be used to fix http://crbug.com/574461

[qyearsley, 2016/06/15 21:54:25]

This kind of thing might be more useful to put in the CL description, to answer
the question: "why is this CL being uploaded now?" If this is committed and then
later the way code is used changes, then the comment would be out of sync with
reality. (This would be "comment rot").

+        self.permissions[file_path] = True
+        mode = mode

[qyearsley, 2016/06/15 21:54:25]

Note, this statement does nothing.

+
     def abspath(self, path):
         if os.path.isabs(path):
             return self.normpath(path)