Allow specificying that only target_os should be used in a gclient file

This allows specificying that a target OS list should override the base
list instead of adding to it. This is useful for iOS builds, where the
desired behavior is to pull only the iOS deps, not the union of the Mac
and iOS deps.


Review URL: https://chromiumcodereview.appspot.com/11363036

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@165671 0039d316-1c4b-4281-b951-d872f2087c98

gclient.py

@@ -55,6 +55,13 @@ Specifying a target OS
 
   Example:
     target_os = [ "android" ]
+
+  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__ = "0.6.4"
@@ -886,7 +893,14 @@ solutions = [
 
     # Append any target OS that is not already being enforced to the tuple.
     target_os = config_dict.get('target_os', [])
-    self._enforced_os = tuple(set(self._enforced_os).union(target_os))
+    if config_dict.get('target_os_only', False):
+      self._enforced_os = tuple(set(target_os))
+    else:
+      self._enforced_os = tuple(set(self._enforced_os).union(target_os))
+
+    if not target_os and config_dict.get('target_os_only', False):
+      raise gclient_utils.Error('Can\'t use target_os_only if target_os is '
+                                'not specified')
 
     deps_to_add = []
     for s in config_dict.get('solutions', []):

tests/gclient_test.py

@@ -307,6 +307,73 @@ class GclientTest(trial_dir.TestCase):
     obj = gclient.GClient.LoadCurrentConfig(options)
     self.assertEqual(['baz', 'unix'], sorted(obj.enforced_os))
 
+  def testTargetOsWithTargetOsOnly(self):
+    """Verifies that specifying a target_os and target_os_only pulls in only
+    the relevant dependencies.
+
+    The target_os variable allows specifying the name of an additional OS which
+    should be considered when selecting dependencies from a DEPS' deps_os. With
+    target_os_only also set, the _enforced_os tuple will be set to only the
+    target_os value.
+    """
+
+    write(
+        '.gclient',
+        'solutions = [\n'
+        '  { "name": "foo",\n'
+        '    "url": "svn://example.com/foo",\n'
+        '  }]\n'
+        'target_os = ["baz"]\n'
+        'target_os_only = True')
+    write(
+        os.path.join('foo', 'DEPS'),
+        'deps = {\n'
+        '  "foo/dir1": "/dir1",'
+        '}\n'
+        'deps_os = {\n'
+        '  "unix": { "foo/dir2": "/dir2", },\n'
+        '  "baz": { "foo/dir3": "/dir3", },\n'
+        '}')
+
+    parser = gclient.Parser()
+    options, _ = parser.parse_args(['--jobs', '1'])
+    options.deps_os = "unix"
+
+    obj = gclient.GClient.LoadCurrentConfig(options)
+    self.assertEqual(['baz'], sorted(obj.enforced_os))
+
+  def testTargetOsOnlyWithoutTargetOs(self):
+    """Verifies that specifying a target_os_only without target_os_only raises
+    an exception.
+    """
+
+    write(
+        '.gclient',
+        'solutions = [\n'
+        '  { "name": "foo",\n'
+        '    "url": "svn://example.com/foo",\n'
+        '  }]\n'
+        'target_os_only = True')
+    write(
+        os.path.join('foo', 'DEPS'),
+        'deps = {\n'
+        '  "foo/dir1": "/dir1",'
+        '}\n'
+        'deps_os = {\n'
+        '  "unix": { "foo/dir2": "/dir2", },\n'
+        '}')
+
+    parser = gclient.Parser()
+    options, _ = parser.parse_args(['--jobs', '1'])
+    options.deps_os = "unix"
+
+    exception_raised = False
+    try:
+      gclient.GClient.LoadCurrentConfig(options)
+    except gclient_utils.Error:
+      exception_raised = True
+    self.assertTrue(exception_raised)
+
   def testTargetOsInDepsFile(self):
     """Verifies that specifying a target_os value in a DEPS file pulls in all
     relevant dependencies.