Fix GetNSExecutablePath for running tests with relative path

base/base_paths_mac.mm

 // Copyright (c) 2012 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.
 
 // Defines base::PathProviderMac which replaces base::PathProviderPosix for Mac
 // in base/path_service.cc.
 
 #include <dlfcn.h>
 #import <Foundation/Foundation.h>
 #include <mach-o/dyld.h>
@@ skipping 14 matching lines @@
   DCHECK(path);
   // Executable path can have relative references ("..") depending on
   // how the app was launched.
   uint32_t executable_length = 0;
   _NSGetExecutablePath(NULL, &executable_length);
   DCHECK_GT(executable_length, 1u);
   std::string executable_path;
   int rv = _NSGetExecutablePath(WriteInto(&executable_path, executable_length),
                                 &executable_length);
   DCHECK_EQ(rv, 0);
-  *path = base::FilePath(executable_path);
+
+  // _NSGetExecutablePath may return paths containing ./ or ../ which makes
+  // FilePath::DirName() work incorrectly, convert it to absolute path so that
+  // paths such as DIR_SOURCE_ROOT can work.
+  *path = base::MakeAbsoluteFilePath(base::FilePath(executable_path));

[Nico, 2013/07/10 18:02:31]

Hm, are you sure these paths never get persisted somewhere? Maybe callers of
this should normpath() instead?

…looks like win and linux return full paths too, so I suppose this is fine.

[brettw, 2013/08/06 04:52:06]

We do want an absolute path here. We should be sure this is the best solution. I
think MakeAbsoluteFilePath does I/O on Posix, which we'd want to avoid if
possible (since I think this function is called on the UI thread). But I don't
have any better ideas.

I think if we're sure this is best the comment would be better worded to just
say that we expect absolute paths to be returned here, since I think DirName()
is probably doing the right thing with the input we're giving it (or it not, we
should fix it).

 }
 
 // Returns true if the module for |address| is found. |path| will contain
 // the path to the module. Note that |path| may not be absolute.
 bool GetModulePathForAddress(base::FilePath* path,
                              const void* address) WARN_UNUSED_RESULT;
 
 bool GetModulePathForAddress(base::FilePath* path, const void* address) {
   Dl_info info;
   if (dladdr(address, &info) == 0)
@@ skipping 57 matching lines @@
       return base::mac::GetUserDirectory(NSCachesDirectory, result);
     case base::DIR_HOME:
       *result = base::mac::NSStringToFilePath(NSHomeDirectory());
       return true;
     default:
       return false;
   }
 }
 
 }  // namespace base