minLength option

docs/javascript.html

@@ -1495,7 +1495,6 @@ <h2>Example</h2>
 
   <hr class="bs-docs-separator">
 
-
   <h2>Usage</h2>
 
   <h3>Via data attributes</h3>
@@ -1529,6 +1528,12 @@ <h3>Options</h3>
        <td>8</td>
        <td>The max number of items to display in the dropdown.</td>
      </tr>
+     <tr>
+       <td>minLength</td>
+       <td>number</td>
+       <td>1</td>
+       <td>The min number of characters entered to start querying.</td>
+     </tr>
      <tr>
        <td>matcher</td>
        <td>function</td>

js/bootstrap-typeahead.js

@@ -33,6 +33,7 @@
     this.sorter = this.options.sorter || this.sorter
     this.highlighter = this.options.highlighter || this.highlighter
     this.updater = this.options.updater || this.updater
+    this.minLength = this.options.minLength || this.minLength
     this.$menu = $(this.options.menu).appendTo('body')
     this.source = this.options.source
     this.shown = false
@@ -78,10 +79,10 @@
 
   , lookup: function (event) {
       var items
-
+      
       this.query = this.$element.val()
 
-      if (!this.query) {
+      if (!this.query || this.query.length < this.minLength) {
         return this.shown ? this.hide() : this
       }
 
@@ -277,6 +278,7 @@
   $.fn.typeahead.defaults = {
     source: []
   , items: 8
+  , minLength: 1
   , menu: '<ul class="typeahead dropdown-menu"></ul>'
   , item: '<li><a href="#"></a></li>'
   }

js/tests/unit/bootstrap-typeahead.js

@@ -181,4 +181,24 @@ $(function () {
 
         typeahead.$menu.remove()
       })
+
+      test("should start querying when minLength is met", function () {
+        var $input = $('<input />').typeahead({
+              source: ['aaaa', 'aaab', 'aaac'],
+              minLength: 3
+            })
+          , typeahead = $input.data('typeahead')
+
+        $input.val('aa')
+        typeahead.lookup()
+
+        equals(typeahead.$menu.find('li').length, 0, 'has 0 items in menu')
+
+        $input.val('aaa')
+        typeahead.lookup()
+
+        equals(typeahead.$menu.find('li').length, 3, 'has 3 items in menu')
+
+        typeahead.$menu.remove()
+      })
 })