testing ng-transclude doesn't work - angularjs

I'm writing two directives that wrap ui-bootstrap's tabset and tab directives.
In order for the content of my directives to be passed to the wrapped directives, I'm using transclusion in both of them.
This works quite well, the only problem is that I'm failing at writing a test that checks that. My test uses a replacement directive as a mock for the wrapped directive, which I replace using $compileProvider before each test.
The test code looks something like this:
beforeEach(module('myModule', function($compileProvider) {
// Mock the internally used 'tab' which is a third party and should not be tested here
$compileProvider.directive('tab', function() {
// Provide a directive with a high priority and 'terminal' set to true, makes sure that
// the mock directive will get executed, and that the real directive will not
var mock = {
priority: 100,
terminal: true,
restrict: 'EAC',
replace: true,
transclude: true,
template: '<div class="mock" ng-transclude></div>'
};
return mock;
});
}));
beforeEach(function() {
inject(function(_$compile_, _$rootScope_) {
$compile = _$compile_;
$rootScope = _$rootScope_;
});
});
beforeEach(function() {
$scope = $rootScope.$new();
});
afterEach(function() {
$scope.$destroy();
});
it('Places the enclosed html inside the tab body', function() {
element = $compile("<div><my-tab>test paragraph</my-tab></div>")($scope);
$scope.$digest();
console.log("element.html() = ", element.html());
expect(element.text().trim()).toEqual("test paragraph");
});
The template of my directive looks something like this:
<div><tab><div ng-transclude></div></tab></div>
The directive module looks something like this:
angular.module('myModule', ['ui.bootstrap'])
.directive('myTab', function() {
return {
restrict: 'E',
replace: true,
transclude: true,
templateUrl: 'templates/my-tab.tpl.html',
scope: {
}
};
});
The result of the print to the console is this:
LOG: 'element.html() = ', '<div class="ng-isolate-scope" id=""><div id="" heading="" class="mock"><ng-transclude></ng-transclude></div></div>'
Any ideas on why the transclusion doesn't take place (again, it works outside of the test just fine) ?
Update
I've since moved on to other things and directives, and ran into this issue again, but now it's more crucial, the reason being, that the directive I place inside the parent directive, requires the parent controller in its link function.
I've done more research into this, and it turns out that for some reason, compiling the mock directive doesn't create an instance of the transcluded content.
The reason I know that, is that I've placed a printout in every hook possible in both directives (both the mock and the transcluded one), i.e. compile, pre-link, post-link and controller constructor, and I see that the only printouts are from the mock directive.
Now, here's the really interesting part: I've tried using the transclude function in the mock directive's link function to "force" the compilation of the transcluded directive, which worked ! (another proof that it didn't take place implicitly).
Where's the catch you ask ? Well, it still doesn't work. This time, since the link function of the transcluded directive fails since it doesn't find the controller of the mock directive. What ?!
Here's the code:
Code
var mod = angular.module('MyModule', []);
mod.directive('parent', function() {
return {
restrict: 'E',
replace: true,
template: '<div class="parent">...</div>',
controller: function() {
this.foo = function() { ... };
}
};
});
mod.directive('child', function() {
return {
restrict: 'E',
require: '^parent',
link: function(scope, element, attrs, parentCtrl) {
parentCtrl.foo();
}
};
});
Test
describe('child directive', function() {
beforeEach(module('MyModule', function($compileProvider) {
$compileProvider.directive('parent', function() {
return {
priority: 100,
terminal: true,
restrict: 'E',
replace: true,
transclude: true,
template: '<div class="mock"><ng-transclude></ng-transclude></div>',
controller: function() {
this.foo = jasmine.createSpy();
},
link: function(scope, element, attrs, ctrls, transcludeFn) {
transcludeFn();
}
};
});
}));
});
This test fails with an error message such as:
Error: [$compile:ctreq] Controller 'parent', required by directive
'child', can't be found!
Any thoughts, ideas, suggestions would be highly appreciated.

Ok, probably the shortest bounty ever in the history of SO ...
The problem was with the terminal: true and priority: 100 properties of the mock directive. I was under the impression (from an article I read online about how to mock directives), that these properties cause the compiler to stop compiling directives with the same name and prioritize the mock directive to be evaluated first.
I was obviously wrong. Looking at this and this, it becomes clear that:
'terminal' stops any other directives that were not processed yet from being processed
'priority' is used to make sure that the mock directive is processed before the directive it is mocking
The problem, is that this causes all other processing to stop, including the ng-transclude directive, which has the default priority of 0.
However, removing these properties causes all hell to break loose, since both directives have been registered, and so forth (I won't burden you with all the gory details). In order to be able to remove these properties, the two directives should reside in different modules, and there should be no dependency between them. In short, when testing the child directive, the only directive named parent that's evaluated should be the mock directive.
In order to support real life usage, I've introduced three modules to the system:
A module for the child directive (no dependencies)
A module for the parent directive (no dependencies)
A module that has no content, but has a dependency on both child and parent modules, which is the only module you'll ever need to add as a dependency in your code
That's pretty much it. I hope it helps anyone else that runs into such problems.

Related

How to access parent's controller function from within a custom directive using *parent's* ControllerAs?

I'm in need of building a transformation directive that transforms custom directives into html.
Input like: <link text="hello world"></link>
should output to: <a class="someclass" ng-click="linkClicked('hello world')"></a>
linkClicked should be called on the parent controller of the directive.
It would have been very easy if I was the one responsible for the html holding the 'link' directive (using isolated scope), but I'm not. It's an as-is input and I have to figure a way to still do it.
There are countless examples on how to do similar bindings using the default scope of the directive, but I'm writing my controllers using John Papa's recommendations with controllerAs, but don't want to create another instance on the controller in the directive.
This is what I have reached so far:
(function () {
'use strict';
angular
.module('app')
.directive('link', link);
link.$inject = ['$compile'];
function link($compile) {
return {
restrict: 'E',
replace: true,
template: '<a class="someclass"></a>',
terminal: true,
priority: 1000,
link: function (scope, element, attributes) {
element.removeAttr('link'); // Remove the attribute to avoid indefinite loop.
element.attr('ng-click', 'linkClicked(\'' + attributes.text + '\')');
$compile(element)(scope);
},
};
}
})();
$scope.linkClicked = function(text){...} in the parent controller works.
element.attr('ng-click', 'abc.linkClicked(..)') in the directive (where the parent's controllerAs is abc) - also works.
The problem is I don't know which controller will use my directive and can't hard-code the 'abc' name in it.
What do you suggest I should be doing?
It's difficult to understand from your question all the constraints that you are facing, but if the only HTML you get is:
<link text="some text">
and you need to generate a call to some function, then the function must either be:
assumed by the directive, or
conveyed to the directive
#1 is problematic because the user of the directive now needs to understand its internals. Still, it's possible if you assume that a function name is linkClicked (or whatever you want to call it), and the user of your directive would have to take special care to alias the function he really needs (could be done with "controllerAs" as well):
<div ng-controller="FooCtrl as foo" ng-init="linkClicked = foo.actualFunctionOfFoo">
...
<link text="some text">
...
</div>
app.directive("link", function($compile){
return {
transclude: "element", // remove the entire element
link: function(scope, element, attrs, ctrl){
var template = '<a class="someclass" ng-click="linkClicked(\'' +
attrs.text +
'\')">link</a>';
$compile(template)(scope, function(clone){
element.after(clone);
});
}
};
});
Demo
#2 is typically achieved via attributes, which isn't possible in your case. But you could also create a sort of "proxy" directive - let's call it onLinkClick - that could execute whatever expression you need:
<div ng-controller="FooCtrl as foo"
on-link-click="foo.actualFunctionOfFoo($data)">
...
<link text="some text">
...
</div>
The link directive now needs to require: "onLinkClick":
app.directive("link", function($compile){
return {
transclude: "element", // remove the entire element
scope: true,
require: "?^onLinkClick",
link: function(scope, element, attrs, ctrl){
if (!ctrl) return;
var template = '<a class="someclass" ng-click="localClick()">link</a>';
scope.localClick = function(){
ctrl.externalFn(attrs.text);
};
$compile(template)(scope, function(clone){
element.after(clone);
});
}
};
});
app.directive("onLinkClick", function($parse){
return {
restrict: "A",
controller: function($scope, $attrs){
var ctrl = this;
var expr = $parse($attrs.onLinkClick);
ctrl.externalFn = function(data){
expr($scope, {$data: data});
};
},
};
});
Demo
Notice that having a link directive would also execute on <link> inside <head>. So, make attempts to detect it and skip everything. For the demo purposes, I used a directive called blink to avoid this issue.

Why is the post link function executed before the transcluded child link functions?

The timing of (pre/post)link functions in AngularJS are well defined in the documentation
Pre-linking function
Executed before the child elements are linked. Not safe to do DOM
transformation since the compiler linking function will fail to locate
the correct elements for linking.
Post-linking function
Executed after the child elements are linked. It is safe to do DOM
transformation in the post-linking function.
and this blog post clearly illustrates this expected order.
But this order does not seem to apply when using ng-transclude and nested directives.
Here is an example for a dropright element (See the Plunkr)
<!-- index.html -->
<dropright>
<col1-item name="a">
<col2-item>1</col2-item>
<col2-item>2</col2-item>
</col1-item>
<col1-item name="b">
...
</col1-item>
</dropright>
// dropright-template.html
<div id="col1-el" ng-transclude></div>
<div id="col2-el">
<!-- Only angularJS will put elements in there -->
</div>
// col1-item-template.html
<p ng-transclude></p>
// col2-item-template.html
<div ng-transclude></div>
The dropright looks like
The directives write a log in the console when their link and controller functions are called.
It usually displays:
But sometimes (after few refreshes), the order is not as expected:
The dropright post-link function is executed before the post-link function of its children.
It may be because, in my particular case, I am calling the dropright controller in the children's directives (See the Plunkr)
angular.module('someApp', [])
.directive('dropright', function() {
return {
restrict: 'E',
transclude: 'true',
controller: function($scope, $element, $attrs) {
console.info('controller - dropright');
$scope.col1Tab = [];
$scope.col2Tab = [];
this.addCol1Item = function(el) {
console.log('(col1Tab pushed)');
$scope.col1Tab.push(el);
};
this.addCol2Item = function(el) {
console.log('(col2Tab pushed)');
$scope.col2Tab.push(el);
};
},
link: {
post: function(scope, element, attrs) {
console.info('post-link - dropright');
// Here, I want to move some of the elements of #col1-el
// into #col2-el
}
},
templateUrl: 'dropright-tpl.html'
};
})
.directive('col1Item', function($interpolate) {
return {
require: '^dropright',
restrict: 'E',
transclude: true,
controller: function() {
console.log('-- controller - col1Item');
},
link: {
post: function(scope, element, attrs, droprightCtrl) {
console.log('-- post-link - col1Item');
droprightCtrl.addCol1Item(element.children()[0]);
}
},
templateUrl: 'col1-tpl.html'
};
})
.directive('col2Item', function() {
var directiveDefinitionObject = {
require: '^dropright',
restrict: 'E',
transclude: true,
controller: function() {
console.log('---- controller - col2Item');
},
link: {
post: function(scope, element, attrs, droprightCtrl) {
console.log('---- post-link - col2Item');
droprightCtrl.addCol2Item(element.children()[0]);
}
},
templateUrl: 'col2-tpl.html'
};
return directiveDefinitionObject;
});
Is there any clean way to execute the link function of a directive after all the link functions of its children while using transclusion?
This is my theory - its not the transclude aspect that is causing the sequence issue but rather the template being a templateUrl. The template needs to be resolved before the post link function get to act on it - hence we say post link function is safe to do DOM manipulation. While we are getting 304s for all the 3 templates - we do have to read them and it ultimately resolves the template promise.
I created a plunker with template instead of templateUrl to prove the corollary. I have hot refresh/plunker Stop/Run many times but I always get link - dropright at the end.
Plunker with template instead of templateUrl
I don't pretend to understand the compile.js code fully. However it does appear that in
compileTemplateUrl function $http.success() resolves the template and then on success the applyDirectivesToNode function is called passing in postLinkFn.
https://github.com/angular/angular.js/blob/master/src/ng/compile.js
This may be just weirdness with Plunker. I tried copying the files to my local IIS, and was not able to replicate the issue.

AngularJS : Child input directive needs to compile in the scope of its parent for ng-model to bind

We have a contact form we use in many applications. There are many default values, validation rules, structure, etc, that are repeated. We're working on a set of directives in order to make the view more semantic and less verbose.
There are a few targets we're shooting for.
Defining the contact form model once in a parent directive like this: <div my-form model='formModel'>. Associated children directives would be able to get the base model from the model attribute.
Supply the default configuration (size, validation rules, placeholders, classes, etc) for each input, but allow the possibility for attributes to be overwritten if necessary. Thus, we are creating child directives using the my-form directive's controller for communication. We also want these child directives to bind to the application controller's model formModel.
I'm having some trouble with implementing this.
formModel is exposed through the parent directive's controller, but I'm having to manually $compile the child directive using scope.$parent in the link function. This seems smelly to me, but if I try to use the child directive's scope the compiled HTML contains the correct attribute (it's visible in the source), but it isn't bound to the controller and it doesn't appear on any scope when inspected with Batarang. I'm guessing I'm adding the attribute too late, but not sure how to add the attribute earlier.
Although I could just use ng-model on each of the child directives, this is exactly what I'm trying to avoid. I want the resulting view to be very clean, and having to specify the model names on every field is repetitive and error-prone. How else can I solve this?
Here is a jsfiddle that has a working but "smelly" setup of what I'm trying to accomplish.
angular.module('myApp', []).controller('myCtrl', function ($scope) {
$scope.formModel = {
name: 'foo',
email: 'foo#foobar.net'
};
})
.directive('myForm', function () {
return {
replace: true,
transclude: true,
scope: true,
template: '<div ng-form novalidate><div ng-transclude></div></div>',
controller: function ($scope, $element, $attrs) {
$scope.model = $attrs.myModel;
this.getModel = function () {
return $scope.model;
};
}
};
})
.directive('myFormName', function ($compile) {
return {
require: '^myForm',
replace: true,
link: function (scope, element, attrs, parentCtrl) {
var modelName = [parentCtrl.getModel(),attrs.id].join('.'),
template = '<input ng-model="' + modelName + '">';
element.replaceWith($compile(template)(scope.$parent));
}
};
});
There is a much simpler solution.
Working Fiddle Here
Parent Form Directive
First, establish an isolated scope for the parent form directive and import the my-model attribute with 2-way binding. This can be done by specifying scope: { model:'=myModel'}. There really is no need to specify prototypical scope inheritance because your directives make no use of it.
Your isolated scope now has the 'model' binding imported, and we can use this fact to compile and link child directives against the parent scope. For this to work, we are going to expose a compile function from the parent directive, that the child directives can call.
.directive('myForm', function ($compile) {
return {
replace: true,
transclude: true,
scope: { model:'=myModel'},
template: '<div ng-form novalidate><div ng-transclude></div></div>',
controller: function ($scope, $element, $attrs) {
this.compile = function (element) {
$compile(element)($scope);
};
}
};
Child Field Directive
Now its time to setup your child directive. In the directive definition, use require:'^myForm' to specify that it must always reside within the parent form directive. In your compile function, add the ng-model="model.{id attribute}". There is no need to figure out the name of the model, because we already know what 'model' will resolve to in the parent scope. Finally, in your link function, just call the parent controller's compile function that you setup earlier.
.directive('myFormName', function () {
return {
require: '^myForm',
scope: false,
compile: function (element, attrs) {
element.attr('ng-model', 'model.' + attrs.id);
return function(scope, element, attrs, parentCtrl) {
parentCtrl.compile(element);
};
}
};
});
This solution is minimal with very little DOM manipulation. Also it preserves the original intent of compiling and linking input form fields against the parent scope, with as little intrusion as possible.
It turns out this question has been asked before (and clarified) here, but never answered.
The question was also asked on the AngularJS mailing list, where the question WAS answered, although the solution results in some smelly code.
Following is Daniel Tabuenca's response from the AngularJS mailing list changed a bit to solve this question.
.directive('foo', function($compile) {
return {
restrict: 'A',
priority: 9999,
terminal: true, //Pause Compilation to give us the opportunity to add our directives
link: function postLink (scope, el, attr, parentCtrl) {
// parentCtrl.getModel() returns the base model name in the parent
var model = [parentCtrl.getModel(), attr.id].join('.');
attr.$set('ngModel', model);
// Resume the compilation phase after setting ngModel
$compile(el, null /* transclude function */, 9999 /* maxPriority */)(scope);
}
};
});
Explanation:
First, the myForm controller is instantiated. This happens before any pre-linking, which makes it possible to expose myForm's variables to the myFormName directive.
Next, myFormName is set to the highest priority (9999) and the property of terminal is set true. The devdocs say:
If set to true then the current priority will be the last set of directives which will execute (any directives at the current priority will still execute as the order of execution on same priority is undefined).
By calling $compile again with the same priority (9999), we resume directive compilation for any directive of a lower priority level.
This use of $compile appears to be undocumented, so use at your own risk.
I'd really like a nicer pattern for follow for this problem. Please let me know if there's a more maintainable way to achieve this end result. Thanks!

Simple Angular Directive

I'm attempting to write my first Angular directive to add pagination functionality to my app.
I'm keeping it simple for now and want to have the directive just share the scope of the controller.
In my controller, I have a scoped var called:
$scope.pages
Inside my directive's linking function, I can do:
console.dir($scope)
to see the contents of the controller's scope object, but if I try to access the pages property, it comes back as undefined.
What am I missing?
Thanks in advance.
myDirectives.directive("mdPagination", function(){
return {
template: '',
restrict: 'A',
priority: 1000,
scope: false,
link: function($scope, el, attrs){
console.dir($scope.pages); //returns undefined
el.text('hello world');
},
}
});
Edit: I'm aware there's pagination modules out there, but my needs are modest and I thought building my own would be an easy way to start learning how to build directives.
The problem you have is directives linking functions are run before controllers are, so you typically can't access scope values during this linking phase. There are a couple other ways to do this. The most immediate way to solve your problem is with $scope.$watch. So something like this should work:
$scope.watch('pages', function(pages) {
console.dir(pages);
});
This works just fine for lost of circumstances. I would also suggest decoupling your controller from the scope it is declared in a bit by using an attribute to pass in an expression (property name basically) for your watch. A simple example might look like this:
<div my-directive="myProperty">
link: function($scope, el, attrs) {
$scope.watch(attrs.myDirective, function(value) {
//do something you need to do with the value here
});
}
However as you add complexity to your directive you may want to give your directive it's own controller to manage state without directly calling watches. This controller can either use a child scope belonging to the directive itself with scope: true or just use the parent scope with scope: false. Your choice will likely depend upon need. Then you could have:
myDirectives.directive("mdPagination", function(){
return {
template: '',
restrict: 'A',
priority: 1000,
controller: ['$scope', '$element', '$attrs', function($scope, $element, $attrs) {
console.dir($scope.pages);
}],
link: function($scope, el, attrs){
$element.text('hello world');
}
}
});
By default, the directive shares its scope with the controller. To do that, you must not having a "scope" attribute in your object, like that:
myDirectives.directive("mdPagination", function(){
return {
template: '',
restrict: 'A',
priority: 1000,
link: function($scope, el, attrs){
console.dir($scope.pages);
el.text('hello world');
},
}
});
#Sandro is right. You set the scope property in your directive to false which means that the scope will not inherit (or share) its properties with the controller. If you remove the false, it should work as you intend it.
The docs for how to use $scope are here: http://code.angularjs.org/1.2.0-rc.3/docs/api/ng.$rootScope.Scope
The developer guide for creating directives has a lot of good info about how to setup your directive so that it gives you the scope you want. Those docs are here: http://code.angularjs.org/1.2.0-rc.3/docs/guide/directive
Hope that helps.

Why AngularJS directive compiling not support nested directives

In my understanding, $compile should be able to support nested directive compilation/link, but we came across an issue that the compilation/link is incomplete - only the outermost directive got rendered into DOM, and the issue only reproduced when both below conditions are true:
The inner directive template is loaded via templateUrl (e.g. async manner)
The compilation is triggered outside Angular context.
I wrote a jsfiddler to demo it, part code listed below, for complete case http://jsfiddle.net/pattern/7KjWP/
myApp.directive('plTest', function($compile){
return {
restrict :'A',
scope: {},
replace: true,
template: '<div>plTest rendered </div>',
link: function (scope, element){
$('#button1').on('click', function(){
var ele;
ele = $compile('<div pl-shared />')(scope);
console.log('plTest compile got : '+ ele[0].outerHTML);
// scope.$apply();
element.append(ele);
});
}
};
});
myApp.directive('plShared', function($compile, $timeout){
return {
restrict: 'A',
scope: {},
replace: true,
link: function (scope, element){
// comment out below line to make render success
//$timeout(function(){});
var el = $compile('<div pl-item></div>')(scope);
console.log('plShared compile got:' + el[0].outerHTML);
element.append(el);
}
};
});
myApp.directive('plItem', function($timeout){
return {
restrict: 'A',
scope:{},
template:'<div>plItem rendered <div pl-avatar/></div>',
link: function(scope){
}
};
});
myApp.directive('plAvatar', function(){
return {
restrict: 'A',
scope: {}
, templateUrl: 'avatar.html'
// ,template: 'content of avatar.html <div pl-image></div>'
};
});
Interestingly, i can workaround the issue by either calling scope.$apply() somewhere after compile() call (line 27)
or adding $timeout(function(){}) call into the link func of one of inner directive (line 41). Is this a defect or by design?
$(foo).on(bar, handler) is a jQuery event, which means AngularJS does not know the specifics of it, and will not (can not) run an apply-digest cycle after it to process all the bindings.
scope.$apply was made for this, and as you rightly say, fixes it. The rule of thumb is: if you implement UI functionality in an AngularJS application using other libraries (specifically: outside of apply-digest cycles), you must call scope.$apply yourself.
HTH!
After element.append(el), try to compile again as you have just modified the DOM.
You could try something such as $compile(element)(scope); or $compile(element.contents())(scope);.
As said before me, I would also change the event handler as follows :
$('#button1').on('click', function(){
scope.$apply( function(){
//blablalba
});
});
Also, justa piece of advice in case you would want to minify your code, I would declare the compile dependency using the following syntax :
.directive('directiveName',['$service1',''$service2,...,'$compile', function($service1, $service2,...,$compile){
//blablabla
}]}

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