Fix diffTypesFor() when using a file extension

src/constants/__tests__/diff-types.test.js

@@ -0,0 +1,21 @@
+/* eslint-env jest */
+
+import { diffTypes, diffTypesFor } from '../diff-types';
+import MediaType from '../../scripts/media-type';
+
+describe('diffTypesFor', () => {
+  it('accepts a file extension', () => {
+    const result = diffTypesFor('.html');
+    expect(result).toContain(diffTypes.HIGHLIGHTED_RENDERED);
+  });
+
+  it('accepts a media type string', () => {
+    const result = diffTypesFor('text/html');
+    expect(result).toContain(diffTypes.HIGHLIGHTED_RENDERED);
+  });
+
+  it('accepts a MediaType object', () => {
+    const result = diffTypesFor(MediaType('text', 'html'));
+    expect(result).toContain(diffTypes.HIGHLIGHTED_RENDERED);
+  });
+});

src/constants/diff-types.js

@@ -81,7 +81,7 @@ const diffTypesByMediaType = {
 export function diffTypesFor (mediaType) {
   let type = null;
   if (typeof mediaType === 'string' && mediaType.startsWith('.')) {
-    type = mediaTypeForExtension(mediaType) || unknownType;
+    type = mediaTypeForExtension[mediaType] || unknownType;
   }
   else {
     type = parseMediaType(mediaType);