Converts absolute paths in the command to relative path.

tools/isolate/isolate.py

 #!/usr/bin/env python
 # 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.
 
 """Does one of the following depending on the --mode argument:
   check     Verifies all the inputs exist, touches the file specified with
             --result and exits.
   hashtable Puts a manifest file and hard links each of the inputs into the
             output directory.
@@ skipping 19 matching lines @@
 
 
 def relpath(path, root):
   """os.path.relpath() that keeps trailing slash."""
   out = os.path.relpath(path, root)
   if path.endswith('/'):
     out += '/'
   return out
 
 
+def to_relative(path, root, relative):
+  """Converts any absolute path to a relative path, only if under root."""
+  if path.startswith(root):
+    logging.info('%s starts with %s' % (path, root))
+    path = os.path.relpath(path, relative)
+  else:
+    logging.info('%s not under %s' % (path, root))
+  return path
+
+
 def separate_inputs_command(args, root, files):
   """Strips off the command line from the inputs.
 
   gyp provides input paths relative to cwd. Convert them to be relative to root.
   OptionParser kindly strips off '--' from sys.argv if it's provided and that's
   the first non-arg value. Manually look up if it was present in sys.argv.
   """
   cmd = []
   if '--' in args:
     i = args.index('--')
@@ skipping 21 matching lines @@
 
   infiles = tree_creator.expand_directories(
         indir, infiles, lambda x: re.match(r'.*\.(svn|pyc)$', x))
 
   # Note the relative current directory.
   # In general, this path will be the path containing the gyp file where the
   # target was defined. This relative directory may be created implicitely if a
   # file from this directory is needed to run the test. Otherwise it won't be
   # created and the process creation will fail. It's up to the caller to create
   # this directory manually before starting the test.
-  relative_cwd = os.path.relpath(os.getcwd(), indir)
+  cwd = os.getcwd()
+  relative_cwd = os.path.relpath(cwd, indir)
+
+  # Workaround make behavior of passing absolute paths.
+  cmd = [to_relative(i, indir, cwd) for i in cmd]
 
   if not cmd:
     # Note that it is exactly the reverse of relative_cwd.
-    cmd = [os.path.join(os.path.relpath(indir, os.getcwd()), infiles[0])]
+    cmd = [os.path.join(os.path.relpath(indir, cwd), infiles[0])]
   if cmd[0].endswith('.py'):
     cmd.insert(0, sys.executable)
 
   # Only hashtable mode really needs the sha-1.
   dictfiles = tree_creator.process_inputs(
       indir, infiles, mode == 'hashtable', read_only)
 
   if not outdir:
     outdir = os.path.dirname(resultfile)
   result = mode_fn(outdir, indir, dictfiles, read_only, cmd, relative_cwd)
@@ skipping 132 matching lines @@
         options.mode,
         options.read_only,
         cmd)
   except tree_creator.MappingError, e:
     print >> sys.stderr, str(e)
     return 1
 
 
 if __name__ == '__main__':
   sys.exit(main())