optimize move item detection

Sergii.Kliuchnyk · Sergii.Kliuchnyk · commit 78ab13e10569 · 2016-08-04T10:43:57.000+03:00
diff --git a/README.md b/README.md
@@ -1,7 +1,7 @@
 simple-diff
 ===========
 
-Lib for simple diff with options
+Lib for simple diff with moved items in array detection
 
 [![Build Status](https://travis-ci.org/redexp/simple-diff.svg?branch=master)](https://travis-ci.org/redexp/simple-diff)
 
@@ -67,43 +67,46 @@ Output
         newValue: 'value01'
     },
     {
-        oldPath: ['prop1'],
-        newPath: ['prop1'],
-        type: 'move-item',
-        oldIndex: 0,
-        newIndex: 1
-    },
-    {
-        oldPath: ['prop1', 0, 'name'],
-        newPath: ['prop1', 1, 'name'],
-        type: 'change',
-        oldValue: 'name1',
-        newValue: 'name01'
+        oldPath: ['prop2'],
+        newPath: ['prop2'],
+        type: 'remove-item',
+        oldIndex: 2,
+        curIndex: 2,
+        newIndex: -1
     },
     {
-        oldPath: ['prop1', 1, 'name'],
-        newPath: ['prop1', 0, 'name'],
-        type: 'remove',
-        oldValue: 'name2',
-        newValue: undefined
+        oldPath: ['prop2'],
+        newPath: ['prop2'],
+        type: 'add-item',
+        oldIndex: -1,
+        curIndex: -1,
+        newIndex: 3,
+        newValue: {
+            id: 5, 
+            name: 'name5'
+        }
     },
     {
-        oldPath: ['prop1'],
-        newPath: ['prop1'],
+        oldPath: ['prop2'],
+        newPath: ['prop2'],
         type: 'move-item',
         oldIndex: 1,
+        curIndex: 1,
         newIndex: 0
     },
     {
-        oldPath: ['prop1'],
-        newPath: ['prop1'],
-        type: 'add-item',
-        oldIndex: -1,
-        newIndex: 3,
-        newValue: {
-            id: 5,
-            name: 'name5'
-        }
+        oldPath: ['prop2', 1, 'name'],
+        newPath: ['prop2', 0, 'name'],
+        type: 'remove',
+        oldValue: 'name2',
+        newValue: undefined
+    },
+    {
+        oldPath: ['prop2', 0, 'name'],
+        newPath: ['prop2', 1, 'name'],
+        type: 'change',
+        oldValue: 'name1',
+        newValue: 'name01'
     },
     {
         oldPath: ['prop3'],
@@ -114,22 +117,20 @@ Output
     }
 ]
 ```
-
- * Installation
- * Options
- * Examples
  
 # Installation
 
 `npm i simple-diff`
 
 `bower i simple-diff`
 
+Lib will look for CommonJS or AMD or will be added global function called `simpleDiff()`.
+
 # Options
 
  * `idProp` - id property for all arrays items. Default value: `id`
  * `idProps` - hash where key is path to array and value is id property. Path examples: `users.list`, `user.list.1.friends`, `users.list.*.friends`
- * `callback` - function which will be called for each "change event". When it used diff will return empty array. Useful for memory management.
+ * `callback` - function which will be called for each event. Useful for memory management because in this case diff will not create array of all events.
  * `addEvent` - name of event when new property added to object. Default value: `add`
  * `changeEvent` - name of event when property value changed. Default value: `change`
  * `removeEvent` - name of event when property removed from object. Default value: `remove`
diff --git a/bower.json b/bower.json
@@ -1,7 +1,7 @@
 {
   "name": "backbone-dom-view",
   "main": "backbone-dom-view.js",
-  "version": "1.1.0",
+  "version": "1.2.0",
   "homepage": "https://github.com/redexp/simple-diff",
   "authors": [
     "Sergii Kliuchnyk <sergiikliuchnyk@gmail.com>"
diff --git a/package.json b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "simple-diff",
-  "version": "1.1.0",
+  "version": "1.2.0",
   "description": "simple diff for object and arrays with options",
   "main": "simple-diff.js",
   "scripts": {
diff --git a/simple-diff.js b/simple-diff.js
@@ -28,7 +28,7 @@
             callback = ops.callback || function (item) {
                 changes.push(item);
             },
-            i, len, prop, id, newIndex;
+            i, len, prop, id;
 
         if (!isObject(oldObj) || !isObject(newObj)) {
             if (oldObj !== newObj) {
@@ -55,99 +55,87 @@
 
             if (sample === UNDEFINED) return changes;
 
-            if (typeof sample === 'object') {
-                var idProp =
-                        (ops.idProps &&
-                        (
-                            ops.idProps[oldPath.map(numberToAsterisk).join('.')] ||
-                            ops.idProps[oldPath.join('.')]
-                        )) || ID_PROP,
-                    oldHash = indexBy(oldObj, idProp),
-                    newHash = indexBy(newObj, idProp);
-
-                for (i = 0, len = oldObj.length; i < len; i++) {
-                    id = oldObj[i][idProp];
-                    newIndex = newObj.indexOf(newHash[id]);
-
-                    if (_DEV_) {
-                        if (typeof id === 'undefined') {
-                            console.error('item #%s do not has "%s" property in array %s', i, idProp, oldPath.join('.'));
-                        }
-                    }
+            var objective = typeof sample === 'object';
 
-                    if (newIndex === -1 || i >= newObj.length || id !== newObj[i][idProp]) {
-                        callback({
-                            oldPath: oldPath,
-                            newPath: newPath,
-                            type: newIndex === -1 ? REMOVE_ITEM_EVENT : MOVE_ITEM_EVENT,
-                            oldIndex: i,
-                            newIndex: newIndex
-                        });
-                    }
+            var idProp =
+                    (objective && ops.idProps &&
+                    (
+                        ops.idProps[oldPath.map(numberToAsterisk).join('.')] ||
+                        ops.idProps[oldPath.join('.')]
+                    )) || ID_PROP,
+                oldHash = objective ? indexBy(oldObj, idProp) : hashOf(oldObj),
+                newHash = objective ? indexBy(newObj, idProp) : hashOf(newObj),
+                curArray = [].concat(oldObj),
+                curIndex, oldIndex;
 
-                    if (newHash.hasOwnProperty(id)) {
-                        diff(oldObj[i], newHash[id], extend({}, ops, {
-                            callback: callback,
-                            oldPath: oldPath.concat(i),
-                            newPath: newPath.concat(newIndex)
-                        }));
-                    }
-                }
+            for (i = 0, len = oldObj.length; i < len; i++) {
+                id = objective ? oldObj[i][idProp] : oldObj[i];
 
-                for (i = 0, len = newObj.length; i < len; i++) {
-                    if (_DEV_) {
-                        if (typeof newObj[i][idProp] === 'undefined') {
-                            console.error('item #%s do not has "%s" property in array %s', i, idProp, newPath.join('.'));
-                        }
-                    }
+                if (!newHash.hasOwnProperty(id)) {
+                    curIndex = curArray.indexOf(oldObj[i]);
+                    curArray.splice(curIndex, 1);
 
-                    if (!oldHash.hasOwnProperty(newObj[i][idProp])) {
-                        callback({
-                            oldPath: oldPath,
-                            newPath: newPath,
-                            type: ADD_ITEM_EVENT,
-                            oldIndex: -1,
-                            newIndex: i,
-                            newValue: newObj[i]
-                        });
-                    }
+                    callback({
+                        oldPath: oldPath,
+                        newPath: newPath,
+                        type: REMOVE_ITEM_EVENT,
+                        oldIndex: i,
+                        curIndex: curIndex,
+                        newIndex: -1
+                    });
                 }
             }
-            else {
-                var oldObjHash = {}, offset = 0;
-
-                for (i = 0, len = oldObj.length; i < len; i++) {
-                    oldObjHash[oldObj[i]] = i;
-
-                    newIndex = newObj.indexOf(oldObj[i]);
-
-                    if (newIndex === -1 || (oldObj[i] !== newObj[i] && oldObj[i] !== newObj[i - offset])) {
-                        callback({
-                            oldPath: oldPath,
-                            newPath: newPath,
-                            type: newIndex === -1 ? REMOVE_ITEM_EVENT : MOVE_ITEM_EVENT,
-                            oldIndex: i,
-                            newIndex: newIndex
-                        });
-                    }
 
-                    if (newIndex === -1) {
-                        offset++;
+            for (i = 0, len = newObj.length; i < len; i++) {
+                id = objective ? newObj[i][idProp] : newObj[i];
+
+                if (!oldHash.hasOwnProperty(id)) {
+                    callback({
+                        oldPath: oldPath,
+                        newPath: newPath,
+                        type: ADD_ITEM_EVENT,
+                        oldIndex: -1,
+                        curIndex: -1,
+                        newIndex: i,
+                        newValue: newObj[i]
+                    });
+
+                    if (i >= curArray.length) {
+                        curArray.push(newObj[i]);
+                    }
+                    else {
+                        curArray.splice(i, 0, newObj[i]);
                     }
                 }
+            }
 
-                for (i = 0, len = newObj.length; i < len; i++) {
-                    if (!oldObjHash.hasOwnProperty(newObj[i])) {
-                        callback({
-                            oldPath: oldPath,
-                            newPath: newPath,
-                            type: ADD_ITEM_EVENT,
-                            oldIndex: -1,
-                            newIndex: i,
-                            newValue: newObj[i]
-                        });
-                    }
+            for (i = 0, len = newObj.length; i < len; i++) {
+                id = objective ? newObj[i][idProp] : newObj[i];
+
+                if (!oldHash.hasOwnProperty(id)) continue;
+
+                oldIndex = oldObj.indexOf(oldHash[id]);
+                curIndex = curArray.indexOf(oldHash[id]);
+
+                if (i !== curIndex) {
+                    callback({
+                        oldPath: oldPath,
+                        newPath: newPath,
+                        type: MOVE_ITEM_EVENT,
+                        oldIndex: oldIndex,
+                        curIndex: curIndex,
+                        newIndex: i
+                    });
+
+                    curArray.splice(curIndex, 1);
+                    curArray.splice(i, 0, oldHash[id]);
                 }
+
+                diff(oldHash[id], newObj[i], extend({}, ops, {
+                    callback: callback,
+                    oldPath: oldPath.concat(oldIndex),
+                    newPath: newPath.concat(i)
+                }));
             }
         }
         else {
@@ -224,6 +212,16 @@
         return hash;
     }
 
+    function hashOf(array) {
+        var hash = {};
+
+        for (var i = 0, len = array.length; i < len; i++) {
+            hash[array[i]] = array[i];
+        }
+
+        return hash;
+    }
+
     function extend(target) {
         for (var i = 1, len = arguments.length; i < len; i++) {
             var source = arguments[i];
diff --git a/simple-diff.min.js b/simple-diff.min.js
diff --git a/test/test.js b/test/test.js

Original file line number	Diff line number	Diff line change
`@@ -1,7 +1,7 @@`
`1`	`1`	`{`
`2`	`2`	`"name": "backbone-dom-view",`
`3`	`3`	`"main": "backbone-dom-view.js",`
`4`		`- "version": "1.1.0",`
	`4`	`+ "version": "1.2.0",`
`5`	`5`	`"homepage": "https://github.com/redexp/simple-diff",`
`6`	`6`	`"authors": [`
`7`	`7`	`"Sergii Kliuchnyk <[email protected]>"`
Original file line number	Diff line number	Diff line change
`@@ -1,6 +1,6 @@`
`1`	`1`	`{`
`2`	`2`	`"name": "simple-diff",`
`3`		`- "version": "1.1.0",`
	`3`	`+ "version": "1.2.0",`
`4`	`4`	`"description": "simple diff for object and arrays with options",`
`5`	`5`	`"main": "simple-diff.js",`
`6`	`6`	`"scripts": {`