Make MB clobber build directories when switching between GYP and GN.

tools/mb/mb_unittest.py

 #!/usr/bin/python
 # Copyright 2015 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.
 
 """Tests for mb.py."""
 
 import json
 import StringIO
 import sys
 import unittest
 
 import mb
 
 
 class FakeMBW(mb.MetaBuildWrapper):
   def __init__(self):
     super(FakeMBW, self).__init__()
     self.files = {}
     self.calls = []
     self.cmds = []
     self.cross_compile = None
     self.out = ''
     self.err = ''
     self.platform = 'linux2'
     self.chromium_src_dir = '/fake_src'
     self.default_config = '/fake_src/tools/mb/mb_config.pyl'
+    self.rmdirs = []
 
   def ExpandUser(self, path):
     return '$HOME/%s' % path
 
   def Exists(self, path):
     return self.files.get(path) is not None
 
   def MaybeMakeDirectory(self, path):
-    pass
+    self.files[path] = True
 
   def ReadFile(self, path):
     return self.files[path]
 
   def WriteFile(self, path, contents):
     self.files[path] = contents
 
   def Call(self, cmd, env=None):
     if env:
       self.cross_compile = env.get('GYP_CROSSCOMPILE')
@@ skipping 10 matching lines @@
       self.err += sep.join(args) + end
     else:
       self.out += sep.join(args) + end
 
   def TempFile(self, mode='w'):
     return FakeFile(self.files)
 
   def RemoveFile(self, path):
     del self.files[path]
 
+  def RemoveDirectory(self, path):
+    self.rmdirs.append(path)
+    files_to_delete = [f for f in self.files if f.startswith(path)]
+    for f in files_to_delete:
+      self.files[f] = None
+
 
 class FakeFile(object):
   def __init__(self, files):
     self.name = '/tmp/file'
     self.buf = ''
     self.files = files
 
   def write(self, contents):
     self.buf += contents
 
   def close(self):
      self.files[self.name] = self.buf
 
 
 TEST_CONFIG = """\
 {
   'common_dev_configs': ['gn_debug'],
   'configs': {
     'gyp_rel_bot': ['gyp', 'rel', 'goma'],
     'gn_debug': ['gn', 'debug'],
+    'gyp_debug': ['gyp', 'debug'],
     'gn_rel_bot': ['gn', 'rel', 'goma'],
     'private': ['gyp', 'rel', 'fake_feature1'],
     'unsupported': ['gn', 'fake_feature2'],
   },
   'masters': {
     'fake_master': {
       'fake_builder': 'gyp_rel_bot',
       'fake_gn_builder': 'gn_rel_bot',
+      'fake_gyp_builder': 'gyp_debug',
     },
   },
   'mixins': {
     'fake_feature1': {
       'gn_args': 'enable_doom_melon=true',
       'gyp_crosscompile': True,
       'gyp_defines': 'doom_melon=1',
     },
     'fake_feature2': {
       'gn_args': 'enable_doom_melon=false',
       'gyp_defaults': 'doom_melon=0',
     },
     'gyp': {'type': 'gyp'},
     'gn': {'type': 'gn'},
     'goma': {
       'gn_args': 'use_goma=true goma_dir="$(goma_dir)"',
       'gyp_defines': 'goma=1 gomadir="$(goma_dir)"',
     },
     'rel': {
       'gn_args': 'is_debug=false',
       'gyp_config': 'Release',
     },
     'debug': {
       'gn_args': 'is_debug=true',
+      'gyp_config': 'Debug',
     },
   },
   'private_configs': ['private'],
   'unsupported_configs': ['unsupported'],
 }
 """
 
 
 class UnitTest(unittest.TestCase):
   def fake_mbw(self, files=None):
@@ skipping 10 matching lines @@
     mbw.ParseArgs(args)
     actual_ret = mbw.args.func()
     if ret is not None:
       self.assertEqual(actual_ret, ret)
     if out is not None:
       self.assertEqual(mbw.out, out)
     if err is not None:
       self.assertEqual(mbw.err, err)
     return mbw
 
+  def test_clobber(self):
+    files = {
+      '/fake_src/out/Debug': None,
+      '/fake_src/out/Debug/mb_type': None,
+    }
+    mbw = self.fake_mbw(files)
+
+    # The first time we run this, the build dir doesn't exist, so no clobber.
+    self.check(['gen', '-c', 'gn_debug', '//out/Debug'], mbw=mbw, ret=0)
+    self.assertEqual(mbw.rmdirs, [])
+    self.assertTrue(mbw.files['/fake_src/out/Debug/mb_type'], 'gn')
+
+    # The second time we run this, the build dir exists and matches, so no
+    # clobber.
+    self.check(['gen', '-c', 'gn_debug', '//out/Debug'], mbw=mbw, ret=0)
+    self.assertEqual(mbw.rmdirs, [])
+    self.assertEqual(mbw.files['/fake_src/out/Debug/mb_type'], 'gn')
+
+    # Now we switch build types; this should result in a clobber.
+    self.check(['gen', '-c', 'gyp_debug', '//out/Debug'], mbw=mbw, ret=0)
+    self.assertEqual(mbw.rmdirs, ['/fake_src/out/Debug'])
+    self.assertEqual(mbw.files['/fake_src/out/Debug/mb_type'], 'gyp')
+
+    # Now we delete mb_type; this checks the case where the build dir
+    # exists but wasn't populated by mb; this should also result in a clobber.
+    del mbw.files['/fake_src/out/Debug/mb_type']
+    self.check(['gen', '-c', 'gyp_debug', '//out/Debug'], mbw=mbw, ret=0)
+    self.assertEqual(mbw.rmdirs,
+                     ['/fake_src/out/Debug', '/fake_src/out/Debug'])
+    self.assertEqual(mbw.files['/fake_src/out/Debug/mb_type'], 'gyp')
+
   def test_gn_analyze(self):
     files = {'/tmp/in.json': """{\
                "files": ["foo/foo_unittest.cc"],
                "targets": ["foo_unittests", "bar_unittests"]
              }"""}
 
     mbw = self.fake_mbw(files)
     mbw.Call = lambda cmd, env=None: (0, 'out/Default/foo_unittests\n', '')
 
     self.check(['analyze', '-c', 'gn_debug', '//out/Default',
@@ skipping 116 matching lines @@
     finally:
       sys.stdout = orig_stdout
 
 
   def test_validate(self):
     self.check(['validate'], ret=0)
 
 
 if __name__ == '__main__':
   unittest.main()