Remove component-emitter dependency

bibimbap.js

@@ -1,6 +1,5 @@
 'use strict';
 
-var emitter       = require('component-emitter');
 var assign        = require('object-assign');
 var flatten       = require('array-flatten');
 var isPlainObject = require('is-plain-object');
@@ -12,10 +11,37 @@ module.exports = Bibimbap;
  */
 function Bibimbap(tree) {
   if (!(this instanceof Bibimbap)) return new Bibimbap(tree);
-  emitter(this);
   this.tree = tree;
+  this.listeners = [];
 }
 
+/**
+ * Subscribe to state changes
+ */
+Bibimbap.prototype.subscribe = function(listener) {
+  this.listeners.push(listener);
+  var isSubscribed = true;
+
+  return function unsubscribe() {
+    if (!isSubscribed) {
+      return;
+    }
+
+    isSubscribed = false;
+    var index = this.listeners.indexOf(listener);
+    this.listeners.splice(index, 1);
+  }
+};
+
+/**
+ * Publish a state change
+ */
+Bibimbap.prototype.publishCommit = function(tree, prev, cursor) {
+  this.listeners.slice().forEach(function(listener) {
+    listener(tree, prev, cursor);
+  });
+};
+
 /**
  * Commit a cursor
  */
@@ -29,7 +55,7 @@ Bibimbap.prototype.commit = function(cursor) {
   // applied to the tree
   cursor.operations = [];
 
-  this.emit('commit', this.tree, prev, cursor);
+  this.publishCommit(this.tree, prev, cursor);
 };
 
 function runOperations(tree, operations) {

package.json

@@ -6,7 +6,6 @@
   "author": "",
   "license": "MIT",
   "dependencies": {
-    "component-emitter": "^1.2.0",
     "array-flatten": "^2.0.0",
     "object-assign": "^4.0.1",
     "is-plain-object": "^2.0.1"

test/bibimbap.js

@@ -143,7 +143,7 @@ describe('Bibimbap', function() {
         var state = new Bibimbap({
           test: 'original'
         });
-        state.on('commit', function(tree, prev, cursor) {
+        state.subscribe(function(tree, prev, cursor) {
           assert.equal('hello', tree.test);
           assert.equal('hello', cursor.get());
           assert.equal('original', prev.test);
@@ -156,7 +156,7 @@ describe('Bibimbap', function() {
         var state = new Bibimbap({
           test: 'original'
         });
-        state.on('commit', function(tree, prev, cursor) {
+        state.subscribe(function(tree, prev, cursor) {
           assert.equal('second', tree.test);
           assert.equal('second', cursor.get());
           assert.equal('original', prev.test);