Merge pull request #25 from gtt-project/test/locale-parity

Pin EN/JA locale parity with a test

Author: dkastl

test/unit/locales_test.rb

@@ -0,0 +1,26 @@
+require File.expand_path('../test_helper', __dir__)
+
+class LocalesTest < ActiveSupport::TestCase
+  LOCALE_DIR = File.expand_path('../../config/locales', __dir__)
+
+  # All leaf key paths of a locale file, e.g. "activerecord.attributes.
+  # issue_datetime.start_time". The files nest, so comparing top-level keys
+  # would miss a string missing deeper down.
+  def leaf_keys(locale)
+    tree = YAML.safe_load_file(File.join(LOCALE_DIR, "#{locale}.yml")).fetch(locale)
+    collect_leaves(tree).sort
+  end
+
+  def collect_leaves(node, prefix = [])
+    node.flat_map do |key, value|
+      path = prefix + [key]
+      value.is_a?(Hash) ? collect_leaves(value, path) : [path.join('.')]
+    end
+  end
+
+  test 'en and ja define the same keys' do
+    # Every string ships in both languages; a key added to one file only
+    # fails here instead of falling back silently in production.
+    assert_equal leaf_keys('en'), leaf_keys('ja')
+  end
+end