import code from friendly_args branch to make filter take flexible args

ratbeard · Mar 1, 2010 · c68ec57 · c68ec57
1 parent 21f5d61
commit c68ec57
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Showing 4 changed files with 888 additions and 2 deletions.
diff --git a/test/flexargs.js b/test/flexargs.js
@@ -0,0 +1,39 @@
+$(document).ready(function() {
+
+  module("Flexargs");
+
+  test('collections: filter', function() {
+    var evens = _.select([1, 2, 3, 4, 5, 6], function(num){ return num % 2 == 0; });
+    equals(evens.join(', '), '2, 4, 6', 'selected each even number');
+
+    evens = _.filter([1, 2, 3, 4, 5, 6], function(num){ return num % 2 == 0; });
+    equals(evens.join(', '), '2, 4, 6', 'aliased as "filter"');
+
+    var dogs = [{name: 'bubbles', age: 5}, {name: 'lily', age: 5}, {name: 'ginger', age: 9}]
+
+    same(
+      _.filter(dogs, {age: 5}),
+      _.filter(dogs, function (dog) { return dog.age == 5; }),
+      'can filter by passing an object of properties to match');
+
+    same(
+      _.filter(dogs, {age: 5, name: 'lily'}),
+      _.filter(dogs, function (dog) { return dog.age == 5 && dog.name == 'lily'; }),
+      'can filter by passing an object of multiple properties to match');
+
+    same(
+      _.filter(dogs, 'age', 5),
+      _.filter(dogs, function (dog) { return dog.age == 5; }),
+      'can filter by passing a key and value to match');
+
+    same(
+      _.filter(dogs, 'name', /l/),
+      _.filter(dogs, function (dog) { return /l/.test(dog.name) }),
+      'passing a regex as a value calls regex.test()');
+
+    same(
+      _.filter(dogs, {name: /e/, age: 5}),
+      _.filter(dogs, function (dog) { return /e/.test(dog.name) && dog.age === 5}),
+      'can pass a regex in an object');
+  });
+});
diff --git a/test/test.html b/test/test.html
@@ -2,13 +2,16 @@
 <html>
 <head>
   <title>Underscore Test Suite</title>
+  <!-- vendor -->
   <link rel="stylesheet" href="vendor/qunit.css" type="text/css" media="screen" />
   <script src="vendor/jquery.js"></script>
   <script src="vendor/qunit.js"></script>
   <script src="vendor/jslitmus.js"></script>
   <script src="../underscore.js"></script>
-
-  <script src="underscore.scraps.js"></script>
+  <!-- code -->
+  <script src="../underscore.flexargs.js"></script>
+  <!-- tests -->
+  <script src="flexargs.js"></script>
 </head>
 <body>
   <h1 id="qunit-header">Underscore Test Suite</h1>

diff --git a/underscore.flexargs.js b/underscore.flexargs.js
@@ -0,0 +1,31 @@
+// Return all the elements that pass a truth test. 
+ // Delegates to JavaScript 1.6's native filter if available.
+ //
+ // TODO: 
+ //  abstract out iterator building code
+var origFilter = _.filter;
+
+ _.filter = function(obj, iterator, context) {
+   if (!_.isFunction(iterator)) {
+     if (typeof iterator === 'object') {  
+       // given props to check, e.g. {age: 5, name: 'h' }
+       // TODO: speed up if only one prop
+       var expected = iterator, iterator = function (item) { 
+         return _.every(expected, function (value, key) {
+           return _.isRegExp(value) ? value.test(item[key]) : value === item[key];
+         });
+       };
+     }
+     else {  
+       // given a key, value pair to check
+       // can totally ignore context arg as it makes no sense if we are building iterator fn.
+       var key = iterator, value = context;
+       iterator = _.isRegExp(value) ? 
+         function(item) { return value.test(item[key]);} :
+         function(item) { return item[key] === value; };
+     }
+   }
+
+   return origFilter(obj, iterator, context)
+
+ };