diff --git a/src/js/git/commands.js b/src/js/git/commands.js
index 2e5c8dad..0b6da0f3 100644
--- a/src/js/git/commands.js
+++ b/src/js/git/commands.js
@@ -22,6 +22,14 @@ var assertIsRef = function(engine, ref) {
   engine.resolveID(ref); // will throw git error if can't resolve
 };
 
+var assertRefNoModifiers = function(ref) {
+  if (/~|\^/.test(ref)) {
+    throw new GitError({
+      msg: intl.str('git-error-exist', {ref: ref})
+    });
+  }
+}
+
 var validateBranchName = function(engine, name) {
   return engine.validateBranchName(name);
 };
@@ -255,6 +263,7 @@ var commandConfig = {
       if (firstArg && isColonRefspec(firstArg)) {
         var refspecParts = firstArg.split(':');
         source = refspecParts[0];
+        assertRefNoModifiers(source);
         destination = validateBranchNameIfNeeded(
           engine,
           crappyUnescape(refspecParts[1])
@@ -264,7 +273,6 @@ var commandConfig = {
         source = firstArg;
         assertIsBranch(engine.origin, source);
         // get o/main locally if main is specified
-        destination = engine.origin.resolveID(source).getPrefixedID();
       } else {
         // can't be detached
         if (engine.getDetachedHead()) {
@@ -277,8 +285,7 @@ var commandConfig = {
         var branch = engine.getOneBeforeCommit('HEAD');
         var branchName = branch.get('id');
         assertBranchIsRemoteTracking(engine, branchName);
-        destination = branch.getRemoteTrackingBranchID();
-        source = destination.replace(ORIGIN_PREFIX, '');
+        source = branch.getRemoteTrackingBranchID().replace(ORIGIN_PREFIX, '');
       }
 
       engine.pull({
@@ -392,6 +399,7 @@ var commandConfig = {
       if (firstArg && isColonRefspec(firstArg)) {
         var refspecParts = firstArg.split(':');
         source = refspecParts[0];
+        assertRefNoModifiers(source);
         destination = validateBranchNameIfNeeded(
           engine,
           crappyUnescape(refspecParts[1])
@@ -405,7 +413,6 @@ var commandConfig = {
         source = firstArg;
         assertIsBranch(engine.origin, source);
         // get o/main locally if main is specified
-        destination = engine.origin.resolveID(source).getPrefixedID();
       }
       if (source) { // empty string fails this check
         assertIsRef(engine.origin, source);
diff --git a/src/js/git/index.js b/src/js/git/index.js
index b8fbafea..1e517c56 100644
--- a/src/js/git/index.js
+++ b/src/js/git/index.js
@@ -397,11 +397,8 @@ GitEngine.prototype.makeBranchIfNeeded = function(branchName) {
   if (this.doesRefExist(branchName)) {
     return;
   }
-  var where = this.findCommonAncestorForRemote(
-    this.getCommitFromRef('HEAD').get('id')
-  );
 
-  return this.validateAndMakeBranch(branchName, this.getCommitFromRef(where));
+  return this.validateAndMakeBranch(branchName, this.rootCommit);
 };
 
 GitEngine.prototype.makeRemoteBranchForRemote = function(branchName) {
@@ -1241,17 +1238,26 @@ GitEngine.prototype.fetch = function(options) {
       this.getCommitFromRef('HEAD')
     );
     return;
-  } else if (options.destination && options.source) {
+  } else if (options.source) {
+    var sourceDestPairs = [];
     didMakeBranch = didMakeBranch || this.makeRemoteBranchIfNeeded(options.source);
-    didMakeBranch = didMakeBranch || this.makeBranchIfNeeded(options.destination);
-    options.didMakeBranch = didMakeBranch;
-
-    return this.fetchCore([{
+    var source = this.origin.resolveID(options.source);
+    if (source.get('type') == 'branch') {
+      sourceDestPairs.push({
+        destination: this.origin.resolveID(options.source).getPrefixedID(),
+        source: options.source
+      });
+	}
+    if (options.destination) {
+      didMakeBranch = didMakeBranch || this.makeBranchIfNeeded(options.destination);
+      sourceDestPairs.push({
         destination: options.destination,
         source: options.source
-      }],
-      options
-    );
+      });
+    }
+    options.didMakeBranch = didMakeBranch;
+    options.dontThrowOnNoFetch = options.dontThrowOnNoFetch || didMakeBranch;
+    return this.fetchCore(sourceDestPairs, options);
   }
   // get all remote branches and specify the dest / source pairs
   var allBranchesOnRemote = this.origin.branchCollection.toArray();
@@ -1409,7 +1415,7 @@ GitEngine.prototype.pull = function(options) {
     return;
   }
 
-  var destBranch = this.resolveID(options.destination);
+  var destBranch = this.resolveID(options.destination || this.origin.resolveID(options.source).getPrefixedID());
   // then either rebase or merge
   if (options.isRebase) {
     this.pullFinishWithRebase(pendingFetch, localBranch, destBranch);