Create a common utility for finding and running binaries in out/

tools/find_run_binary.py

+#!/usr/bin/python
+# Copyright (c) 2014 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.
+
+"""Module that finds and runs a binary by looking in the likely locations."""
+
+
+import os
+import subprocess
+import sys
+
+
+def run_command(args):
+  """Runs a program from the command line and returns stdout.
+
+  Args:
+    args: Command line to run, as a list of string parameters. args[0] is the
+          binary to run.
+
+  Returns:
+    stdout from the program, as a single string.
+
+  Raises:
+    Exception: the program exited with a nonzero return code.
+  """
+  proc = subprocess.Popen(args,
+                          stdout=subprocess.PIPE,
+                          stderr=subprocess.PIPE)
+  (stdout, stderr) = proc.communicate()
+  if proc.returncode is not 0:
+    raise Exception('command "%s" failed: %s' % (args, stderr))
+  return stdout
+
+
+def find_path_to_program(program):
+  """Returns path to an existing program binary.
+
+  Args:
+    program: Basename of the program to find (e.g., 'render_pictures').
+
+  Returns:
+    Absolute path to the program binary, as a string.
+
+  Raises:
+    Exception: unable to find the program binary.
+  """
+  trunk_path = os.path.abspath(os.path.join(os.path.dirname(__file__),
+                                            os.pardir))
+  possible_paths = [os.path.join(trunk_path, 'out', 'Release', program),
+                    os.path.join(trunk_path, 'out', 'Debug', program),
+                    os.path.join(trunk_path, 'out', 'Release',
+                                 program + '.exe'),
+                    os.path.join(trunk_path, 'out', 'Debug',
+                                 program + '.exe')]
+  for try_path in possible_paths:
+    if os.path.isfile(try_path):
+      return try_path
+  raise Exception('cannot find %s in paths %s; maybe you need to '
+                  'build %s?' % (program, possible_paths, program))
+