Build in callback context option

1 files changed, 44 insertions, 7 deletions

diff --git a/lib/dom-batch.js b/lib/dom-batch.js
index 1e1bcb4..2f80172 100644
--- a/lib/dom-batch.js
+++ b/lib/dom-batch.js
@@ -46,8 +46,8 @@
    * @param  {Function} fn
    * @api public
    */
-  DomBatch.prototype.read = function(fn) {
-    this.reads.push(fn);
+  DomBatch.prototype.read = function(fn, ctx) {
+    add(this.reads, fn, ctx);
     this.request('read');
   };
 
@@ -58,8 +58,8 @@
    * @param  {Function} fn
    * @api public
    */
-  DomBatch.prototype.write = function(fn) {
-    this.writes.push(fn);
+  DomBatch.prototype.write = function(fn, ctx) {
+    add(this.writes, fn, ctx);
     this.request('write');
   };
 
@@ -128,12 +128,22 @@
    * Calls each job in
    * the list passed.
    *
+   * If a context has been
+   * stored on the function
+   * then it is used, else the
+   * current `this` is used.
+   *
    * @param  {Array} list
    * @api private
    */
   DomBatch.prototype.run = function(list) {
+    var fn;
+    var ctx;
+
     while (list.length) {
-      list.shift().call(this);
+      fn = list.shift();
+      ctx = fn._dbctx || this;
+      fn.call(ctx);
     }
   };
 
@@ -167,8 +177,35 @@
    * Util
    */
 
-  function remove(array, item) {
-    var index = array.indexOf(item);
+  /**
+   * Adds a function to
+   * the given array.
+   *
+   * If a context is given
+   * it is stored on the
+   * function object for
+   * later.
+   *
+   * @param {Array}   array
+   * @param {Function} fn
+   * @param {Object}   ctx
+   * @api private
+   */
+  function add(array, fn, ctx) {
+    if (ctx) fn._dbctx = ctx;
+    array.push(fn);
+  }
+
+  /**
+   * Removes a function
+   * from the given array.
+   *
+   * @param  {Array} array
+   * @param  {Function} item
+   * @api private
+   */
+  function remove(array, fn) {
+    var index = array.indexOf(fn);
     if (~index) array.splice(index, 1);
   }