Fix the YCM tests on Mac.

tools/vim/tests/chromium.ycm_extra_conf_unittest.py

 #!/usr/bin/env python
 
 # Copyright 2015 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.
 
 """Tests for chromium.ycm_extra_conf.
 
 These tests should be getting picked up by the PRESUBMIT.py in /tools/vim.
 Currently the tests only run on Linux and require 'ninja' to be available on
@@ skipping 56 matching lines @@
       |   |  DEPS
       |   |  three.cc
       |   |
       |   +-- .git
       |
       +-- out
           |
           +-- gn
                 build.ninja
     """
-    self.chrome_root = os.path.abspath(os.path.normpath(
+    self.chrome_root = os.path.abspath(os.path.realpath(

[asanka, 2016/09/01 18:20:58]

Why is this necessary on Mac?

[Sidney San Martín, 2016/09/01 22:18:04]

The temp directories on Mac are symlinks (/tmp -> /private/tmp, /var ->
/private/var), and that triggers a couple of bugs in these scripts. The first
one relates to ninja_output.GetNinjaOutputDirectory(), which performs some path
transformations on lines 40-42:

    out = os.path.realpath(os.path.join(chrome_root, f))
    if os.path.isdir(out):
      output_dirs.append(os.path.relpath(out, start = chrome_root))

Those path transformations go like this:

    os.path.join('/tmp/chrome_root359/', 'out')
      -> '/tmp/chrome_root359/out'
    os.path.realpath('/tmp/chrome_root359/out')
      -> '/private/tmp/chrome_root359/out'
    os.path.relpath('/private/tmp/chrome_root359/out', start =
'/tmp/chrome_root359/')
      -> '../../private/tmp/chrome_root359/out'

Later, on line 46:

    os.path.join('/tmp/chrome_root359', '../../private/tmp/chrome_root359/out')
      -> '/tmp/chrome_root359/../../private/tmp/chrome_root359/out'

The os.listdir() on line 47 follows each .. link and effectively tries to list:

    /private/private/tmp/chrome_root359/out

…and throws. I fixed this in a new patchset, but there's still a second issue.
Chromium_ycmExtraConfTest.NormalizeString() looks like this:

    replace(self.chrome_root, '[SRC]').replace('\\', '/')

When self.chrome_root includes a symlink, the path returned by Ninja will have
resolved that symlink, so the replacement will fail (or, in this case, miss the
/private at the beginning and return "/private[SRC]"). This particular change to
resolve symlinks up front resolves that. I moved it to a better spot in the new
patchset, though.

         os.path.join(self.test_root, 'src')))
     self.out_dir = os.path.join(self.chrome_root, 'out', 'gn')
 
     os.makedirs(self.chrome_root)
     os.makedirs(os.path.join(self.chrome_root, '.git'))
     os.makedirs(self.out_dir)
 
     CreateFile(os.path.join(self.test_root, '.gclient'))
     CreateFile(os.path.join(self.chrome_root, 'DEPS'))
     CreateFile(os.path.join(self.chrome_root, 'three.cc'))
@@ skipping 297 matching lines @@
         '-Wno-unknown-warning-option',
         '-I[OUT]/a',
         '--sysroot=[SRC]/build/sysroot-image',
         ])
 
 if __name__ == '__main__':
   if not os.path.isfile('chromium.ycm_extra_conf.py'):
     print('The test must be run from src/tools/vim/ directory')
     sys.exit(1)
   unittest.main()