Fix the YCM tests on Mac.

tools/vim/tests/chromium.ycm_extra_conf_unittest.py

Index: tools/vim/tests/chromium.ycm_extra_conf_unittest.py
diff --git a/tools/vim/tests/chromium.ycm_extra_conf_unittest.py b/tools/vim/tests/chromium.ycm_extra_conf_unittest.py
index bb3dca421b8c3a05a66e9ae62d2d971ddc1a8e36..9f6b74589eea70df25fba44fbeb410f33ec9c9a6 100755
--- a/tools/vim/tests/chromium.ycm_extra_conf_unittest.py
+++ b/tools/vim/tests/chromium.ycm_extra_conf_unittest.py
@@ -74,7 +74,7 @@ class Chromium_ycmExtraConfTest(unittest.TestCase):
           +-- 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')