feat(typeahead): add typeaheadSelectOnExact support

- Add support for `typeahead-select-on-exact` for exact matches

Closes #3365
Fixes #3310

src/typeahead/docs/readme.md

@@ -27,6 +27,10 @@ The typeahead directives provide several attributes:
 * `typeahead-editable` <i class="glyphicon glyphicon-eye-open"></i>
    _(Defaults: true)_ :
    Should it restrict model values to the ones selected from the popup only ?
+
+* `typeahead-focus-first`
+   _(Defaults: true)_ :
+   Should the first match automatically be focused as you type?
 
 * `typeahead-input-formatter` <i class="glyphicon glyphicon-eye-open"></i>
    _(Defaults: undefined)_ :
@@ -39,11 +43,15 @@ The typeahead directives provide several attributes:
 * `typeahead-min-length` <i class="glyphicon glyphicon-eye-open"></i>
    _(Defaults: 1)_ :
    Minimal no of characters that needs to be entered before typeahead kicks-in
-
+   
 * `typeahead-on-select($item, $model, $label)`
    _(Defaults: null)_ :
    A callback executed when a match is selected
 
+* `typeahead-select-on-exact`
+   _(Defaults: false)_ :
+   Should it automatically select an item when there is one option that exactly matches the user input?
+
 * `typeahead-template-url` <i class="glyphicon glyphicon-eye-open"></i>
    :
    Set custom item template
@@ -52,10 +60,6 @@ The typeahead directives provide several attributes:
    _(Defaults: 0)_ :
    Minimal wait time after last character typed before typeahead kicks-in
 
-* `typeahead-focus-first`
-   _(Defaults: true)_ :
-   Should the first match automatically be focused as you type?
-
 * `typeahead-select-on-blur`
    _(Defaults: false)_ :
    On blur, select the currently highlighted match

src/typeahead/test/typeahead.spec.js

@@ -456,6 +456,63 @@ describe('typeahead tests', function () {
       expect(inputEl.val()).toEqual('AL');
     });
   });
+
+  describe('select on exact match', function(){
+
+    it('should select on an exact match when set', function () {
+
+      $scope.onSelect = jasmine.createSpy('onSelect');
+      var element = prepareInputEl('<div><input ng-model="result" typeahead-editable="false" typeahead-on-select="onSelect()" typeahead="item for item in source | filter:$viewValue" typeahead-select-on-exact="true"></div>');
+      var inputEl = findInput(element);
+
+      changeInputValueTo(element, 'bar');
+
+      expect($scope.result).toEqual('bar');
+      expect(inputEl.val()).toEqual('bar');
+      expect(element).toBeClosed();
+      expect($scope.onSelect).toHaveBeenCalled();
+    });
+
+    it('should not select on an exact match by default', function () {
+
+      $scope.onSelect = jasmine.createSpy('onSelect');
+      var element = prepareInputEl('<div><input ng-model="result" typeahead-editable="false" typeahead-on-select="onSelect()" typeahead="item for item in source | filter:$viewValue"></div>');
+      var inputEl = findInput(element);
+
+      changeInputValueTo(element, 'bar');
+
+      expect($scope.result).toBeUndefined();
+      expect(inputEl.val()).toEqual('bar');
+      expect($scope.onSelect.calls.any()).toBe(false);
+    });
+
+    it('should not be case sensitive when select on an exact match', function () {
+
+      $scope.onSelect = jasmine.createSpy('onSelect');
+      var element = prepareInputEl('<div><input ng-model="result" typeahead-editable="false" typeahead-on-select="onSelect()" typeahead="item for item in source | filter:$viewValue" typeahead-select-on-exact="true"></div>');
+      var inputEl = findInput(element);
+
+      changeInputValueTo(element, 'BaR');
+
+      expect($scope.result).toEqual('bar');
+      expect(inputEl.val()).toEqual('bar');
+      expect(element).toBeClosed();
+      expect($scope.onSelect).toHaveBeenCalled();
+    });
+
+    it('should not auto select when not a match with one potential result left', function () {
+
+      $scope.onSelect = jasmine.createSpy('onSelect');
+      var element = prepareInputEl('<div><input ng-model="result" typeahead-editable="false" typeahead-on-select="onSelect()" typeahead="item for item in source | filter:$viewValue" typeahead-select-on-exact="true"></div>');
+      var inputEl = findInput(element);
+
+      changeInputValueTo(element, 'fo');
+
+      expect($scope.result).toBeUndefined();
+      expect(inputEl.val()).toEqual('fo');
+      expect($scope.onSelect.calls.any()).toBe(false);
+    });
+  });
 
   describe('pop-up interaction', function () {
     var element;

src/typeahead/typeahead.js

@@ -67,6 +67,9 @@ angular.module('ui.bootstrap.typeahead', ['ui.bootstrap.position', 'ui.bootstrap
       var appendToBody =  attrs.typeaheadAppendToBody ? originalScope.$eval(attrs.typeaheadAppendToBody) : false;
 
       var focusFirst = originalScope.$eval(attrs.typeaheadFocusFirst) !== false;
+
+      //If input matches an item of the list exactly, select it automatically
+      var selectOnExact = attrs.typeaheadSelectOnExact ? originalScope.$eval(attrs.typeaheadSelectOnExact) : false;
 
       //INTERNAL VARIABLES
 
@@ -133,6 +136,15 @@ angular.module('ui.bootstrap.typeahead', ['ui.bootstrap.position', 'ui.bootstrap
           element.attr('aria-activedescendant', getMatchId(index));
         }
       });
+
+      var inputIsExactMatch = function(inputValue, index) {
+
+        if (scope.matches.length > index && inputValue) {
+          return inputValue.toUpperCase() === scope.matches[index].label.toUpperCase();
+        }
+
+        return false;
+      };
 
       var getMatchesAsync = function(inputValue) {
 
@@ -166,6 +178,11 @@ angular.module('ui.bootstrap.typeahead', ['ui.bootstrap.position', 'ui.bootstrap
               recalculatePosition();
 
               element.attr('aria-expanded', true);
+
+              //Select the single remaining option if user input matches
+              if (selectOnExact && scope.matches.length === 1 && inputIsExactMatch(inputValue, 0)) {
+                scope.select(0);
+              }
             } else {
               resetMatches();
             }