[style_var_gen] Add BaseGenerator.Validate() test and fix bug.

This CL fixes a bug where Validate() wouldn't catch that a color wasn't
defined for the default mode. It also adds some tests.

Bug: 1018654
Change-Id: I226124d6a4fc51020b96e85309fda42a98132abd
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2251126Reviewed-by: Giovanni Ortuño Urquidi <ortuno@chromium.org>
Commit-Queue: calamity <calamity@chromium.org>
Cr-Commit-Position: refs/heads/master@{#780173}

tools/style_variable_generator/base_generator.py

@@ -75,10 +75,13 @@ class BaseGenerator:
     def AddJSONFileToModel(self, path):
         self.in_files.append(path)
         with open(path, 'r') as f:
-            # TODO(calamity): Add allow_duplicate_keys=False once pyjson5 is
-            # rolled.
-            data = json5.loads(
-                f.read(), object_pairs_hook=collections.OrderedDict)
+            self.AddJSONToModel(f.read())
+
+    def AddJSONToModel(self, json_string):
+        # TODO(calamity): Add allow_duplicate_keys=False once pyjson5 is
+        # rolled.
+        data = json5.loads(json_string,
+                           object_pairs_hook=collections.OrderedDict)
 
         try:
             for name, value in data['colors'].items():
@@ -103,7 +106,7 @@ class BaseGenerator:
         return template.render(params)
 
     def Validate(self):
-        def CheckIsInDefaultModel(name):
+        def CheckColorInDefaultMode(name):
             if name not in self._mode_variables[self._default_mode].colors:
                 raise ValueError(
                     "%s not defined in '%s' mode" % (name, self._default_mode))
@@ -112,10 +115,11 @@ class BaseGenerator:
         # default mode.
         for m in self._mode_variables.values():
             for name, value in m.colors.items():
+                CheckColorInDefaultMode(name)
                 if value.var:
-                    CheckIsInDefaultModel(value.var)
+                    CheckColorInDefaultMode(value.var)
                 if value.rgb_var:
-                    CheckIsInDefaultModel(value.rgb_var[:-4])
+                    CheckColorInDefaultMode(value.rgb_var[:-4])
 
         # TODO(calamity): Check for circular references.
 

tools/style_variable_generator/base_generator_test.py

+# Copyright 2019 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.
+
+from base_generator import BaseGenerator
+import unittest
+
+
+class BaseGeneratorTest(unittest.TestCase):
+    def setUp(self):
+        self.generator = BaseGenerator()
+
+    def testMissingColor(self):
+        # google_grey_900 is missing.
+        self.generator.AddJSONToModel('''
+{
+  colors: {
+    cros_default_text_color: {
+      light: "$google_grey_900",
+      dark: "rgb(255, 255, 255)",
+    },
+  },
+}
+        ''')
+        self.assertRaises(ValueError, self.generator.Validate)
+
+        # Add google_grey_900.
+        self.generator.AddJSONToModel('''
+{
+  colors: {
+    google_grey_900: "rgb(255, 255, 255)",
+  }
+}
+        ''')
+        self.generator.Validate()
+
+    def testMissingDefaultModeColor(self):
+        # google_grey_900 is missing in the default mode (light).
+        self.generator.AddJSONToModel('''
+{
+  colors: {
+    google_grey_900: { dark: "rgb(255, 255, 255)", },
+  }
+}
+        ''')
+        self.assertRaises(ValueError, self.generator.Validate)
+
+        # Add google_grey_900 to light mode.
+        self.generator.AddJSONToModel('''
+{
+  colors: {
+    google_grey_900: { light: "rgb(255, 255, 255)", }
+  }
+}
+        ''')
+        self.generator.Validate()
+
+
+if __name__ == '__main__':
+    unittest.main()