Invoke event listener with several arguments in array #13

modules/eventlisteners.js

@@ -1,11 +1,14 @@
 var is = require('../is');
 
 function arrInvoker(arr) {
-  return function() { arr[0](arr[1]); };
+  return function() {
+    // Special case when length is two, for performance
+    arr.length === 2 ? arr[0](arr[1]) : arr[0].apply(undefined, arr.splice(1));
+  };
 }
 
-function fnInvoker(arr) {
-  return function(ev) { arr[0](ev); };
+function fnInvoker(o) {
+  return function(ev) { o.fn(ev); };
 }
 
 function updateEventListeners(oldVnode, vnode) {
@@ -19,16 +22,17 @@ function updateEventListeners(oldVnode, vnode) {
       if (is.array(cur)) {
         elm.addEventListener(name, arrInvoker(cur));
       } else {
-        cur = [cur];
+        cur = {fn: cur};
         on[name] = cur;
         elm.addEventListener(name, fnInvoker(cur));
       }
-    } else if (old.length === 2) {
-      old[0] = cur[0]; // Deliberately modify old array since it's
-      old[1] = cur[1]; // captured in closure created with `arrInvoker`
+    } else if (is.array(old)) {
+      // Deliberately modify old array since it's captured in closure created with `arrInvoker`
+      old.length = cur.length;
+      for (var i = 0; i < old.length; ++i) old[i] = cur[i];
       on[name]  = old;
     } else {
-      old[0] = cur;
+      old.fn = cur;
       on[name] = old;
     }
   }

package.json

@@ -1,6 +1,6 @@
 {
   "name": "snabbdom",
-  "version": "0.2.3",
+  "version": "0.2.4",
   "description": "A virtual DOM library with focus on simplicity, modularity, powerful features and performance.",
   "main": "snabbdom.js",
   "directories": {

snabbdom.js

@@ -29,7 +29,7 @@ function createKeyToOldIdx(children, beginIdx, endIdx) {
   return map;
 }
 
-function createRmCb(parentElm, childElm, listeners) {
+function createRmCb(childElm, listeners) {
   return function() {
     if (--listeners === 0) childElm.parentElement.removeChild(childElm);
   };
@@ -109,7 +109,7 @@ function init(modules) {
         if (isDef(ch.sel)) {
           invokeDestroyHook(ch);
           listeners = cbs.remove.length + 1;
-          rm = createRmCb(parentElm, ch.elm, listeners);
+          rm = createRmCb(ch.elm, listeners);
           for (i = 0; i < cbs.remove.length; ++i) cbs.remove[i](ch, rm);
           if (isDef(i = ch.data) && isDef(i = i.hook) && isDef(i = i.remove)) {
             i(ch, rm);

test/core.js

@@ -416,63 +416,6 @@ describe('snabbdom', function() {
       });
     });
   });
-  describe('event handling', function() {
-    it('attaches click event handler to element', function() {
-      var result = [];
-      function clicked(ev) { result.push(ev); }
-      var vnode = h('div', {on: {click: clicked}}, [
-        h('a', 'Click my parent'),
-      ]);
-      patch(vnode0, vnode);
-      elm.click();
-      assert.equal(1, result.length);
-    });
-    it('does not attach new listener', function() {
-      var result = [];
-      //function clicked(ev) { result.push(ev); }
-      var vnode1 = h('div', {on: {click: function(ev) { result.push(1); }}}, [
-        h('a', 'Click my parent'),
-      ]);
-      var vnode2 = h('div', {on: {click: function(ev) { result.push(2); }}}, [
-        h('a', 'Click my parent'),
-      ]);
-      patch(vnode0, vnode1);
-      elm.click();
-      patch(vnode1, vnode2);
-      elm.click();
-      assert.deepEqual(result, [1, 2]);
-    });
-    it('does calls handler for function in array', function() {
-      var result = [];
-      function clicked(ev) { result.push(ev); }
-      var vnode = h('div', {on: {click: [clicked, 1]}}, [
-        h('a', 'Click my parent'),
-      ]);
-      patch(vnode0, vnode);
-      elm.click();
-      assert.deepEqual(result, [1]);
-    });
-    it('handles changed value in array', function() {
-      var result = [];
-      function clicked(ev) { result.push(ev); }
-      var vnode1 = h('div', {on: {click: [clicked, 1]}}, [
-        h('a', 'Click my parent'),
-      ]);
-      var vnode2 = h('div', {on: {click: [clicked, 2]}}, [
-        h('a', 'Click my parent'),
-      ]);
-      var vnode3 = h('div', {on: {click: [clicked, 3]}}, [
-        h('a', 'Click my parent'),
-      ]);
-      patch(vnode0, vnode1);
-      elm.click();
-      patch(vnode1, vnode2);
-      elm.click();
-      patch(vnode2, vnode3);
-      elm.click();
-      assert.deepEqual(result, [1, 2, 3]);
-    });
-  });
   describe('hooks', function() {
     describe('element hooks', function() {
       it('calls `create` listener before inserted into parent but after children', function() {

test/eventlisteners.js

@@ -0,0 +1,90 @@
+var assert = require('assert');
+
+var snabbdom = require('../snabbdom');
+var patch = snabbdom.init([
+  require('../modules/eventlisteners.js'),
+]);
+var h = require('../h');
+
+describe('event listeners', function() {
+  var elm, vnode0;
+  beforeEach(function() {
+    elm = document.createElement('div');
+    vnode0 = elm;
+  });
+  it('attaches click event handler to element', function() {
+    var result = [];
+    function clicked(ev) { result.push(ev); }
+    var vnode = h('div', {on: {click: clicked}}, [
+      h('a', 'Click my parent'),
+    ]);
+    patch(vnode0, vnode);
+    elm.click();
+    assert.equal(1, result.length);
+  });
+  it('does not attach new listener', function() {
+    var result = [];
+    //function clicked(ev) { result.push(ev); }
+    var vnode1 = h('div', {on: {click: function(ev) { result.push(1); }}}, [
+      h('a', 'Click my parent'),
+    ]);
+    var vnode2 = h('div', {on: {click: function(ev) { result.push(2); }}}, [
+      h('a', 'Click my parent'),
+    ]);
+    patch(vnode0, vnode1);
+    elm.click();
+    patch(vnode1, vnode2);
+    elm.click();
+    assert.deepEqual(result, [1, 2]);
+  });
+  it('does calls handler for function in array', function() {
+    var result = [];
+    function clicked(ev) { result.push(ev); }
+    var vnode = h('div', {on: {click: [clicked, 1]}}, [
+      h('a', 'Click my parent'),
+    ]);
+    patch(vnode0, vnode);
+    elm.click();
+    assert.deepEqual(result, [1]);
+  });
+  it('handles changed value in array', function() {
+    var result = [];
+    function clicked(ev) { result.push(ev); }
+    var vnode1 = h('div', {on: {click: [clicked, 1]}}, [
+      h('a', 'Click my parent'),
+    ]);
+    var vnode2 = h('div', {on: {click: [clicked, 2]}}, [
+      h('a', 'Click my parent'),
+    ]);
+    var vnode3 = h('div', {on: {click: [clicked, 3]}}, [
+      h('a', 'Click my parent'),
+    ]);
+    patch(vnode0, vnode1);
+    elm.click();
+    patch(vnode1, vnode2);
+    elm.click();
+    patch(vnode2, vnode3);
+    elm.click();
+    assert.deepEqual(result, [1, 2, 3]);
+  });
+  it('handles changed several values in array', function() {
+    var result = [];
+    function clicked() { result.push([].slice.call(arguments)); }
+    var vnode1 = h('div', {on: {click: [clicked, 1, 2, 3]}}, [
+      h('a', 'Click my parent'),
+    ]);
+    var vnode2 = h('div', {on: {click: [clicked, 1, 2]}}, [
+      h('a', 'Click my parent'),
+    ]);
+    var vnode3 = h('div', {on: {click: [clicked, 2, 3]}}, [
+      h('a', 'Click my parent'),
+    ]);
+    patch(vnode0, vnode1);
+    elm.click();
+    patch(vnode1, vnode2);
+    elm.click();
+    patch(vnode2, vnode3);
+    elm.click();
+    assert.deepEqual(result, [[1, 2, 3], [1, 2], [2, 3]]);
+  });
+});

test/index.js

@@ -1,4 +1,5 @@
 require('./core');
 require('./style');
+require('./eventlisteners');
 require('./attachto');
 require('./thunk');