Include all files with 0% coverage in report

spec/javascripts/test_bundle.js

@@ -42,3 +42,38 @@ testsContext.keys().forEach(function (path) {
     });
   }
 });
+
+// workaround: include all source files to find files with 0% coverage
+// see also https://github.com/deepsweet/istanbul-instrumenter-loader/issues/15
+describe('Uncovered files', function () {
+  // the following files throw errors because of undefined variables
+  const troubleMakers = [
+    './blob_edit/blob_edit_bundle.js',
+    './cycle_analytics/components/stage_plan_component.js',
+    './cycle_analytics/components/stage_staging_component.js',
+    './cycle_analytics/components/stage_test_component.js',
+    './diff_notes/components/jump_to_discussion.js',
+    './diff_notes/components/resolve_count.js',
+    './merge_conflicts/components/inline_conflict_lines.js',
+    './merge_conflicts/components/parallel_conflict_lines.js',
+    './network/branch_graph.js',
+  ];
+
+  const sourceFiles = require.context('~', true, /^\.\/(?!application\.js).*\.(js|es6)$/);
+  sourceFiles.keys().forEach(function (path) {
+    // ignore if there is a matching spec file
+    if (testsContext.keys().indexOf(`${path.replace(/\.js(\.es6)?$/, '')}_spec`) > -1) {
+      return;
+    }
+
+    it(`includes '${path}'`, function () {
+      try {
+        sourceFiles(path);
+      } catch (err) {
+        if (troubleMakers.indexOf(path) === -1) {
+          expect(err).toBeNull();
+        }
+      }
+    });
+  });
+});