Fix: wrong prefix on PR files changed

lib/containers/pr-changed-files-container.js

@@ -59,7 +59,16 @@ export default class PullRequestChangedFilesContainer extends React.Component {
   }
 
   buildPatch(rawDiff) {
-    const diffs = parseDiff(rawDiff);
+    const diffs = parseDiff(rawDiff).map(diff => {
+      // diff coming from API will have the defaul git diff prefixes a/ and b/
+      // e.g. a/file1.js and b/file2.js
+      // see https://git-scm.com/docs/git-diff#_generating_patches_with_p
+      return {
+        ...diff,
+        newPath: diff.newPath ? diff.newPath.replace(/^[a|b]\//, '') : diff.newPath,
+        oldPath: diff.oldPath ? diff.oldPath.replace(/^[a|b]\//, '') : diff.oldPath,
+      };
+    });
     return buildMultiFilePatch(diffs);
   }
 

test/containers/pr-changed-files-container.test.js

@@ -2,7 +2,7 @@ import React from 'react';
 import {shallow} from 'enzyme';
 import {parse as parseDiff} from 'what-the-diff';
 
-import rawDiff from '../fixtures/diffs/raw-diff';
+import {rawDiff, rawDiffWithPathPrefix} from '../fixtures/diffs/raw-diff';
 import {buildMultiFilePatch} from '../../lib/models/patch';
 import {getEndpoint} from '../../lib/models/endpoint';
 
@@ -72,6 +72,13 @@ describe('PullRequestChangedFilesContainer', function() {
       assert.strictEqual(diffURL, 'https://api.github.com/repos/smashwilson/pushbot/pulls/12');
     });
 
+    it('builds multifilepatch without the a/ and b/ prefixes in file paths', function() {
+      const wrapper = shallow(buildApp());
+      const {filePatches} = wrapper.instance().buildPatch(rawDiffWithPathPrefix);
+      assert.notMatch(filePatches[0].newFile.path, /^[a|b]\//);
+      assert.notMatch(filePatches[0].oldFile.path, /^[a|b]\//);
+    });
+
     it('passes loaded diff data through to the controller', async function() {
       const wrapper = shallow(buildApp({
         token: '4321',

test/fixtures/diffs/raw-diff.js

@@ -1,4 +1,5 @@
 import dedent from 'dedent-js';
+
 const rawDiff = dedent`
   diff --git file.txt file.txt
   index 83db48f..bf269f4 100644
@@ -10,4 +11,15 @@ const rawDiff = dedent`
   +new line
    line3
 `;
-export default rawDiff;
+const rawDiffWithPathPrefix = dedent`
+  diff --git a/badpath.txt b/badpath.txt
+  index af607bb..cfac420 100644
+  --- a/badpath.txt
+  +++ b/badpath.txt
+  @@ -1,2 +1,3 @@
+    line0
+  -line1
+  +line1.5
+  +line2
+`;
+export {rawDiff, rawDiffWithPathPrefix};