diff --git a/‎lib/commit.js‎
Lines changed: 13 additions & 8 deletions b/‎lib/commit.js‎
Lines changed: 13 additions & 8 deletions
@@ -169,16 +169,21 @@ Commit.prototype.parents = function() {
 Commit.prototype.getDiff = function(callback) {
   var commit = this;
 
-  return commit.getParents().then(function(parents) {
-    var diffs = parents.map(function(parent) {
-      return parent.getTree().then(function(parentTree) {
-        return commit.getTree().then(function(thisTree) {
-          return thisTree.diff(parentTree);
+  return commit.getTree().then(function(thisTree) {
+    return commit.getParents().then(function(parents) {
+      var diffs;
+      if (parents.length) {
+        diffs = parents.map(function(parent) {
+          return parent.getTree().then(function(parentTree) {
+            return thisTree.diff(parentTree);
+          });
         });
-      });
-    });
+      } else {
+        diffs = [thisTree.diff(null)];
+      }
 
-    return Promise.all(diffs);
+      return Promise.all(diffs);
+    });
   }).then(function(diffs) {
     if (typeof callback === "function") {
       callback(null, diffs);