Makes copy_ex handle directories

build/android/gyp/copy_ex.py

 #!/usr/bin/env python
 #
 # Copyright 2014 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """Copies files to a directory."""
 
 import optparse
+import os
 import shutil
 import sys
 
 from util import build_utils
 
 
 def main(args):
   args = build_utils.ExpandFileArgs(args)
 
   parser = optparse.OptionParser()
@@ skipping 12 matching lines @@
 
   if options.clear:
     build_utils.DeleteDirectory(options.dest)
     build_utils.MakeDirectory(options.dest)
 
   files = []
   for file_arg in options.files:
     files += build_utils.ParseGypList(file_arg)
 
   for f in files:
-    shutil.copy(f, options.dest)
+    if os.path.isdir(f):
+      shutil.copytree(f, os.path.join(options.dest, os.path.basename(f)))

[cjhopman, 2015/05/08 22:58:55]

I would require that options.clear be set if any directories are copied.

[sky, 2015/05/08 23:38:31]

Why is it different than with files? The same problem exists in either case, you
may not realize there are stale files around. Seems to me you're arguing for
always clearing, which seems separate from adding support for directories.

I had started adding the warning, but then realized it starts sounding very
weird. Basically it comes down to something like "we don't trust you, use
clear=true when copying directories."

[cjhopman, 2015/05/08 23:57:05]

Yeah, exactly, I don't trust people (including myself) to do this correctly.

In the case where you are only copying files, I would expect that you will be
able to pass your actual outputs to the consumer (because you were able to tell
copy_ex your actual inputs).

The problem is that if you are copying a directory here, then you are probably
telling whoever uses the outputs to look in a directory (because if you can tell
the consumer the exact files, then why not just tell the copy step the exact
files). If you're doing that, then it's really difficult for the consumer to
detect and ignore stale files.

I would consider requiring options.stamp, too, but that's really only necessary
in gyp, not GN. The issue is that you need to be able to specify some sort of
output that is an input to the consumer so that the build knows the consumer
needs to run. In GN, just having a dependency is enough for that.

+    else:
+      shutil.copy(f, options.dest)
 
   if options.depfile:
     build_utils.WriteDepfile(
         options.depfile,
         files + build_utils.GetPythonDependencies())

[cjhopman, 2015/05/08 22:58:55]

The depfile should list the entire contents of the directories that were copied.

[sky, 2015/05/08 23:38:31]

I totally missed that. I believe I've fixed it.

 
   if options.stamp:
     build_utils.Touch(options.stamp)
 
 
 if __name__ == '__main__':
   sys.exit(main(sys.argv[1:]))