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(
-        os.path.join(self.test_root, 'src')))
+    self.chrome_root = 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 12 matching lines @@
     return [self.NormalizeString(s) for s in list_of_strings]
 
   def setUp(self):
     self.actual_chrome_root = os.path.normpath(
         os.path.join(os.path.dirname(os.path.abspath(__file__)), '../../..'))
     sys.path.append(os.path.join(self.actual_chrome_root, 'tools', 'vim'))
     self.test_data_path = os.path.join(self.actual_chrome_root, 'tools', 'vim',
                                        'tests', 'data')
     self.ycm_extra_conf = imp.load_source('ycm_extra_conf',
                                           'chromium.ycm_extra_conf.py')
-    self.test_root = tempfile.mkdtemp()
+    self.test_root = os.path.realpath(tempfile.mkdtemp())

[asanka, 2016/09/02 15:05:13]

Shall we avoid calling realpath() here and try to get rid of .relpath() uses
elsewhere? I think we could end up masking similar bugs if we call realpath()
here. Optionally I'd suggest explicitly setting things up so that self.test_root
contains a symlink somewhere so that we can smoke out similar issues.

[Sidney San Martín, 2016/09/09 14:55:49]

I like it :). See the latest patch set — some uses of relpath are useful, like
getting the path of a file relative to the out dir, but it turns out that
realpath was *not* useful.

     self.SetUpFakeChromeTreeBelowPath()
 
   def tearDown(self):
     if self.test_root:
       shutil.rmtree(self.test_root)
 
   def testNinjaIsAvailable(self):
     p = subprocess.Popen(['ninja', '--version'], stdout=subprocess.PIPE)
     _, _ = p.communicate()
     self.assertFalse(p.returncode)
@@ skipping 263 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()