feat(typeahead): add 'select on blur' option.

- Add `select-on-blur` option

Closes #3445

src/typeahead/docs/readme.md

@@ -55,3 +55,7 @@ The typeahead directives provide several attributes:
 * `typeahead-focus-first`
    _(Defaults: true)_ :
    Should the first match automatically be focused as you type?
+
+* `select-on`blur`
+   _(Defaults: false)_ :
+   On blur, select the currently highlighted match

src/typeahead/test/typeahead.spec.js

@@ -384,6 +384,32 @@ describe('typeahead tests', function () {
       expect(element).toBeClosed();
     });
 
+    it('should not select any match on blur without \'select-on-blur=true\' option', function () {
+
+      var element = prepareInputEl('<div><input ng-model="result" typeahead="item for item in source | filter:$viewValue"></div>');
+      var inputEl = findInput(element);
+
+      changeInputValueTo(element, 'b');
+      inputEl.blur(); // input loses focus
+
+      // no change
+      expect($scope.result).toEqual('b');
+      expect(inputEl.val()).toEqual('b');
+    });
+
+    it('should select a match on blur with \'select-on-blur=true\' option', function () {
+
+      var element = prepareInputEl('<div><input ng-model="result" typeahead="item for item in source | filter:$viewValue" typeahead-select-on-blur="true"></div>');
+      var inputEl = findInput(element);
+
+      changeInputValueTo(element, 'b');
+      inputEl.blur(); // input loses focus
+
+      // first element should be selected
+      expect($scope.result).toEqual('bar');
+      expect(inputEl.val()).toEqual('bar');
+    });
+
     it('should select match on click', function () {
 
       var element = prepareInputEl('<div><input ng-model="result" typeahead="item for item in source | filter:$viewValue"></div>');

src/typeahead/typeahead.js

@@ -59,6 +59,9 @@ angular.module('ui.bootstrap.typeahead', ['ui.bootstrap.position', 'ui.bootstrap
       //a callback executed when a match is selected
       var onSelectCallback = $parse(attrs.typeaheadOnSelect);
 
+      //should it select highlighted popup value when losing focus?
+      var isSelectOnBlur = angular.isDefined(attrs.typeaheadSelectOnBlur) ? originalScope.$eval(attrs.typeaheadSelectOnBlur) : false;
+
       var inputFormatter = attrs.typeaheadInputFormatter ? $parse(attrs.typeaheadInputFormatter) : undefined;
 
       var appendToBody =  attrs.typeaheadAppendToBody ? originalScope.$eval(attrs.typeaheadAppendToBody) : false;
@@ -357,6 +360,11 @@ angular.module('ui.bootstrap.typeahead', ['ui.bootstrap.position', 'ui.bootstrap
       });
 
       element.bind('blur', function (evt) {
+        if (isSelectOnBlur && scope.activeIdx >= 0) {
+          scope.$apply(function () {
+            scope.select(scope.activeIdx);
+          });
+        }
         hasFocus = false;
       });