Reintroduce RunCommand cleanup and unit tests. Fixed previous issue, and

lib/cros_build_lib.py

 # Copyright (c) 2010 The Chromium OS Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """Common python commands used by various build scripts."""
 
 import inspect
 import os
 import re
 import subprocess
@@ skipping 32 matching lines @@
     input: input to pipe into this command through stdin.
     enter_chroot: this command should be run from within the chroot.  If set,
       cwd must point to the scripts directory.
     num_retries: the number of retries to perform before dying
 
   Returns:
     If exit_code is True, returns the return code of the shell command.
     Else returns the output of the shell command.
 
   Raises:
-    Exception:  Raises RunCommandException on error with optional error_message.
+    Exception:  Raises RunCommandException on error with optional error_message,
+                but only if exit_code, and error_ok are both False. 
   """
   # Set default for variables.
   stdout = None
   stderr = None
   stdin = None
   output = ''
 
   # Modify defaults based on parameters.
   if redirect_stdout:  stdout = subprocess.PIPE
   if redirect_stderr:  stderr = subprocess.PIPE
   if input:  stdin = subprocess.PIPE
   if enter_chroot:  cmd = ['./enter_chroot.sh', '--'] + cmd
 
   # Print out the command before running.
   if print_cmd:
     Info('PROGRAM(%s) -> RunCommand: %r in dir %s' %
          (GetCallerName(), cmd, cwd))
 
   for retry_count in range(num_retries + 1):
-    try:
-      proc = subprocess.Popen(cmd, cwd=cwd, stdin=stdin,
-                              stdout=stdout, stderr=stderr)
-      (output, error) = proc.communicate(input)
-      if exit_code and retry_count == num_retries:
-        return proc.returncode
 
-      if proc.returncode == 0:
-        break
+    # If it's not the first attempt, it's a retry
+    if retry_count > 0 and print_cmd:
+      Info('PROGRAM(%s) -> RunCommand: retrying %r in dir %s' %
+           (GetCallerName(), cmd, cwd))
 
+    proc = subprocess.Popen(cmd, cwd=cwd, stdin=stdin,
+                            stdout=stdout, stderr=stderr)
+    (output, error) = proc.communicate(input)
+
+    # if the command worked, don't retry any more.
+    if proc.returncode == 0:
+      break
+
+  # If they asked for an exit_code, give it to them on success or failure
+  if exit_code:
+    return proc.returncode
+
+  # If the command (and all retries) failed, handle error result
+  if proc.returncode != 0:
+    if error_ok:
+      Warning('Command "%r" failed.\n' % (cmd) +
+              (error_message or error or output or ''))
+    else:
       raise RunCommandException('Command "%r" failed.\n' % (cmd) +
                                 (error_message or error or output or ''))
-    except RunCommandException as e:
-      if not error_ok and retry_count == num_retries:
-        raise e
-      else:
-        Warning(str(e))
-        if print_cmd:
-          Info('PROGRAM(%s) -> RunCommand: retrying %r in dir %s' %
-               (GetCallerName(), cmd, cwd))
 
+  # return final result
   return output
 
 
 def RunCommandCaptureOutput(cmd, print_cmd=True, cwd=None, input=None,
                             enter_chroot=False,
                             combine_stdout_stderr=True,
                             verbose=False):
   """Runs a shell command. Differs from RunCommand, because it allows
      you to run a command and capture the exit code, output, and stderr
      all at the same time.
@@ skipping 153 matching lines @@
   either via a VM or remote machine on the same network.
   """
   ifconfig_output = RunCommand(['/sbin/ifconfig', device],
                                redirect_stdout=True, print_cmd=False)
   match = re.search('.*inet addr:(\d+\.\d+\.\d+\.\d+).*', ifconfig_output)
   if match:
     return match.group(1)
   else:
     Warning('Failed to find ip address in %s' % ifconfig_output)
     return None