Make mb take in multiple isolate maps.

Bug: 726431
Change-Id: Ia8b6e3ccbf2f66b1038c6a15be03899367859965
Reviewed-on: https://chromium-review.googlesource.com/896570Reviewed-by: John Budorick <jbudorick@chromium.org>
Commit-Queue: Zhiling Huang <hzl@chromium.org>
Cr-Commit-Position: refs/heads/master@{#534209}

tools/mb/mb.py

@@ -91,9 +91,11 @@ class MetaBuildWrapper(object):
                         help='path to config file '
                              '(default is %(default)s)')
       subp.add_argument('-i', '--isolate-map-file', metavar='PATH',
-                        default=self.default_isolate_map,
                         help='path to isolate map file '
-                             '(default is %(default)s)')
+                             '(default is %(default)s)',
+                        default=[],
+                        action='append',
+                        dest='isolate_map_files')
       subp.add_argument('-g', '--goma-dir',
                         help='path to goma directory')
       subp.add_argument('--android-version-code',
@@ -581,14 +583,26 @@ class MetaBuildWrapper(object):
     self.mixins = contents['mixins']
 
   def ReadIsolateMap(self):
-    if not self.Exists(self.args.isolate_map_file):
-      raise MBErr('isolate map file not found at %s' %
-                  self.args.isolate_map_file)
-    try:
-      return ast.literal_eval(self.ReadFile(self.args.isolate_map_file))
-    except SyntaxError as e:
-      raise MBErr('Failed to parse isolate map file "%s": %s' %
-                  (self.args.isolate_map_file, e))
+    if not self.args.isolate_map_files:
+      self.args.isolate_map_files = [self.default_isolate_map]
+
+    for f in self.args.isolate_map_files:
+      if not self.Exists(f):
+        raise MBErr('isolate map file not found at %s' % f)
+    isolate_maps = {}
+    for isolate_map in self.args.isolate_map_files:
+      try:
+        isolate_map = ast.literal_eval(self.ReadFile(isolate_map))
+        duplicates = set(isolate_map).intersection(isolate_maps)
+        if duplicates:
+          raise MBErr(
+              'Duplicate targets in isolate map files: %s.' %
+              ', '.join(duplicates))
+        isolate_maps.update(isolate_map)
+      except SyntaxError as e:
+        raise MBErr(
+            'Failed to parse isolate map file "%s": %s' % (isolate_map, e))
+    return isolate_maps
 
   def ConfigFromArgs(self):
     if self.args.config:

tools/mb/mb_unittest.py

@@ -437,6 +437,75 @@ class UnitTest(unittest.TestCase):
                   mbw.files)
 
 
+  def test_multiple_isolate_maps(self):
+    files = {
+      '/tmp/swarming_targets': 'cc_perftests\n',
+      '/fake_src/testing/buildbot/gn_isolate_map.pyl': (
+          "{'cc_perftests': {"
+          "  'label': '//cc:cc_perftests',"
+          "  'type': 'raw',"
+          "  'args': [],"
+          "}}\n"
+      ),
+      '/fake_src/testing/buildbot/gn_isolate_map2.pyl': (
+          "{'cc_perftests2': {"
+          "  'label': '//cc:cc_perftests',"
+          "  'type': 'raw',"
+          "  'args': [],"
+          "}}\n"
+      ),
+      'c:\\fake_src\out\Default\cc_perftests.exe.runtime_deps': (
+          "cc_perftests\n"
+      ),
+    }
+    mbw = self.fake_mbw(files=files, win32=True)
+    self.check(['gen',
+                '-c', 'debug_goma',
+                '--swarming-targets-file', '/tmp/swarming_targets',
+                '--isolate-map-file',
+                '/fake_src/testing/buildbot/gn_isolate_map.pyl',
+                '--isolate-map-file',
+                '/fake_src/testing/buildbot/gn_isolate_map2.pyl',
+                '//out/Default'], mbw=mbw, ret=0)
+    self.assertIn('c:\\fake_src\\out\\Default\\cc_perftests.isolate',
+                  mbw.files)
+    self.assertIn('c:\\fake_src\\out\\Default\\cc_perftests.isolated.gen.json',
+                  mbw.files)
+
+
+  def test_duplicate_isolate_maps(self):
+    files = {
+      '/tmp/swarming_targets': 'cc_perftests\n',
+      '/fake_src/testing/buildbot/gn_isolate_map.pyl': (
+          "{'cc_perftests': {"
+          "  'label': '//cc:cc_perftests',"
+          "  'type': 'raw',"
+          "  'args': [],"
+          "}}\n"
+      ),
+      '/fake_src/testing/buildbot/gn_isolate_map2.pyl': (
+          "{'cc_perftests': {"
+          "  'label': '//cc:cc_perftests',"
+          "  'type': 'raw',"
+          "  'args': [],"
+          "}}\n"
+      ),
+      'c:\\fake_src\out\Default\cc_perftests.exe.runtime_deps': (
+          "cc_perftests\n"
+      ),
+    }
+    mbw = self.fake_mbw(files=files, win32=True)
+    # Check that passing duplicate targets into mb fails.
+    self.check(['gen',
+                '-c', 'debug_goma',
+                '--swarming-targets-file', '/tmp/swarming_targets',
+                '--isolate-map-file',
+                '/fake_src/testing/buildbot/gn_isolate_map.pyl',
+                '--isolate-map-file',
+                '/fake_src/testing/buildbot/gn_isolate_map2.pyl',
+                '//out/Default'], mbw=mbw, ret=1)
+
+
   def test_isolate(self):
     files = {
       '/fake_src/out/Default/toolchain.ninja': "",