gclient: in managed mode, warn if .gclient has a mismatched URL

gclient.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.
 
 """Meta checkout manager supporting both Subversion and GIT."""
 # Files
 #   .gclient      : Current client configuration, written by 'config' command.
 #                   Format is a Python script defining 'solutions', a list whose
 #                   entries each are maps binding the strings "name" and "url"
@@ skipping 60 matching lines @@
 #
 #   If the "target_os_only" key is also present and true, then *only* the
 #   operating systems listed in "target_os" will be used.
 #
 #   Example:
 #     target_os = [ "ios" ]
 #     target_os_only = True
 
 __version__ = '0.7'
 
+import atexit

[borenet, 2014/03/14 13:30:57]

Is atexit acceptable for this? It would be nice to have a way to gather
warnings/errors as we run and dump them all out at the end. That'd be especially
good for https://codereview.chromium.org/189913020/, to warn more loudly that
we've moved directories around.

[iannucci, 2014/03/17 17:38:40]

Hm. I would probably wrap atexit instead of directly registering callbacks, if
only because atexit works in LIFO order, which could be weird. Having a
print_on_exit(...) function could register a single atexit and then keep a queue
internally for messages to print.

[borenet, 2014/03/17 17:41:33]

Alternatively, I can just call the _CheckConfig method right before finishing,
rather than at the beginning.

 import copy
 import json
 import logging
 import optparse
 import os
 import platform
 import posixpath
 import pprint
 import re
 import sys
@@ skipping 946 matching lines @@
     if options.deps_os:
       enforced_os = options.deps_os.split(',')
     else:
       enforced_os = [self.DEPS_OS_CHOICES.get(sys.platform, 'unix')]
     if 'all' in enforced_os:
       enforced_os = self.DEPS_OS_CHOICES.itervalues()
     self._enforced_os = tuple(set(enforced_os))
     self._root_dir = root_dir
     self.config_content = None
 
+  def _CheckConfig(self):
+    """Verify that the config matches any existing checkout."""
+    for dep in self.dependencies:
+      if dep.managed:
+        scm = gclient_scm.CreateSCM(dep.url, self.root_dir, dep.name)
+        actual_url = scm.GetActualRemoteURL()
+        if actual_url and not scm.DoesRemoteURLMatch():
+          def print_warning():
+            print >> sys.stderr, ('''
+################################################################################
+################################### WARNING! ###################################
+################################################################################
+
+Your .gclient file seems to be broken. The requested URL is different from what
+is actually checked out in %(checkout_path)s. In the future this will be an
+error.
+
+Expected: %(expected_url)s (%(expected_scm)s)
+Actual:   %(actual_url)s (%(actual_scm)s)
+
+You should ensure that the URL listed in .gclient is correct and either change
+it or fix the checkout. If you're managing your own git checkout in
+%(checkout_path)s but the URL in .gclient is for an svn repository, you probably
+want to set 'managed': False in .gclient.
+
+################################################################################
+################################################################################
+################################################################################
+'''  % {'checkout_path': os.path.join(self.root_dir, dep.name),
+        'expected_url': dep.url,
+        'expected_scm': gclient_scm.GetScmName(dep.url),
+        'actual_url': actual_url,
+        'actual_scm': gclient_scm.GetScmName(actual_url)})
+
+          atexit.register(print_warning)
+
   def SetConfig(self, content):
     assert not self.dependencies
     config_dict = {}
     self.config_content = content
     try:
       exec(content, config_dict)
     except SyntaxError, e:
       gclient_utils.SyntaxErrorToError('.gclient', e)
 
     # Append any target OS that is not already being enforced to the tuple.
@@ skipping 18 matching lines @@
             s.get('managed', True),
             s.get('custom_deps', {}),
             s.get('custom_vars', {}),
             s.get('custom_hooks', []),
             s.get('deps_file', 'DEPS'),
             True))
       except KeyError:
         raise gclient_utils.Error('Invalid .gclient file. Solution is '
                                   'incomplete: %s' % s)
     self.add_dependencies_and_close(deps_to_add, config_dict.get('hooks', []))
+    self._CheckConfig()
     logging.info('SetConfig() done')
 
   def SaveConfig(self):
     gclient_utils.FileWrite(os.path.join(self.root_dir,
                                          self._options.config_filename),
                             self.config_content)
 
   @staticmethod
   def LoadCurrentConfig(options):
     """Searches for and loads a .gclient file relative to the current working
@@ skipping 592 matching lines @@
     raise gclient_utils.Error('client not configured; see \'gclient config\'')
 
   if options.revisions and options.head:
     # TODO(maruel): Make it a parser.error if it doesn't break any builder.
     print('Warning: you cannot use both --head and --revision')
 
   if options.verbose:
     # Print out the .gclient file.  This is longer than if we just printed the
     # client dict, but more legible, and it might contain helpful comments.
     print(client.config_content)
+
   ret = client.RunOnDeps('update', args)
   if options.output_json:
     slns = {}
     for d in client.subtree(True):
       normed = d.name.replace('\\', '/').rstrip('/') + '/'
       slns[normed] = {
           'revision': d.got_revision,
           'scm': d.used_scm.name if d.used_scm else None,
       }
     with open(options.output_json, 'wb') as f:
@@ skipping 214 matching lines @@
     raise
   except (gclient_utils.Error, subprocess2.CalledProcessError), e:
     print >> sys.stderr, 'Error: %s' % str(e)
     return 1
 
 
 if '__main__' == __name__:
   sys.exit(Main(sys.argv[1:]))
 
 # vim: ts=2:sw=2:tw=80:et: