Don't crash if .git is there but .git/HEAD isn't. Fixes #329

Author: tmcw

lib/git/url_prefix.js

@@ -12,14 +12,18 @@ var getRemoteOrigin = require('remote-origin-url');
  * @throws {Error} if the root is not a git repo
  */
 function getGithubURLPrefix(root) {
-  var head = fs.readFileSync(path.join(root, '.git', 'HEAD'), 'utf8');
-  var branch = head.match(/ref\: (.*)/);
-  if (branch) {
-    var sha = fs.readFileSync(path.join(root, '.git', branch[1]), 'utf8');
-  } else {
-    sha = head;
+  try {
+    var head = fs.readFileSync(path.join(root, '.git', 'HEAD'), 'utf8');
+    var branch = head.match(/ref\: (.*)/);
+    if (branch) {
+      var sha = fs.readFileSync(path.join(root, '.git', branch[1]), 'utf8');
+    } else {
+      sha = head;
+    }
+    return urlFromGit(getRemoteOrigin.sync(root)) + '/blob/' + sha.trim() + '/';
+  } catch (e) {
+    return null;
   }
-  return urlFromGit(getRemoteOrigin.sync(root)) + '/blob/' + sha.trim() + '/';
 }
 
 module.exports = getGithubURLPrefix;

lib/github.js

@@ -18,10 +18,12 @@ function getFileRoot(file) {
 module.exports = function (comment) {
   var root = getFileRoot(comment.context.file);
   var urlPrefix = getGithubURLPrefix(root);
-  comment.context.path = comment.context.file.replace(root + '/', '');
-  comment.context.github = urlPrefix +
-    comment.context.file.replace(root + '/', '') +
-    '#L' + comment.context.loc.start.line + '-' +
-    'L' + comment.context.loc.end.line;
+  if (urlPrefix) {
+    comment.context.path = comment.context.file.replace(root + '/', '');
+    comment.context.github = urlPrefix +
+      comment.context.file.replace(root + '/', '') +
+      '#L' + comment.context.loc.start.line + '-' +
+      'L' + comment.context.loc.end.line;
+  }
   return comment;
 };

test/lib/git/mock_repo.js

@@ -33,5 +33,15 @@ module.exports = {
         }
       }
     }
+  },
+  malformed: {
+    '/my': {
+      repository: {
+        path: {
+          '.git': {},
+          'index.js': 'module.exports = 42;'
+        }
+      }
+    }
   }
 };

test/lib/github.js

@@ -39,3 +39,22 @@ test('github', function (t) {
 
   t.end();
 });
+
+test('malformed repository', function (t) {
+
+  mock(mockRepo.malformed);
+
+  t.equal(evaluate(function () {
+    /**
+     * get one
+     * @returns {number} one
+     */
+    function getOne() {
+      return 1;
+    }
+  })[0].context.github, undefined, 'does not crash');
+
+  mock.restore();
+
+  t.end();
+});