feat(angular): allows to use custom Ability instances and improves …

…tree shaking support

Relates to #249 BREAKING CHANGE: removes `AbilityModule.forRoot()` method and default `Ability` provider.

**Before**

```js
import { AbilityModule } from '@casl/angular'

@NgModule({
  // ...
  imports: [
    AbilityModule.forRoot()
  ],
  providers: [
    // ...
  ]
})
export class AppModule {}
```

**After**

```js
import { PureAbility, Ability } from '@casl/ability'
import { AbilityModule } from '@casl/angular'

@NgModule({
  // ...
  imports: [
    AbilityModule
  ],
  providers: [
    // PureAbility is injected by `can` & `able` pipes
    { provide: PureAbility, useValue: new Ability() },
    // the next line can be added as a migration workaround
    { provide: Ability, useExisting: PureAbility },
    // ...
  ]
})
export class AppModule {}
```

packages/casl-angular/spec/can_pipe.spec.js

@@ -1,4 +1,4 @@
-import { AbilityBuilder } from '@casl/ability'
+import { defineAbility } from '@casl/ability'
 import { CanPipe } from '../dist/es6'
 
 describe('Can pipe', () => {
@@ -7,7 +7,7 @@ describe('Can pipe', () => {
   let changeDetectorRef
 
   beforeEach(() => {
-    ability = AbilityBuilder.define(can => can('read', 'all'))
+    ability = defineAbility(can => can('read', 'all'))
     changeDetectorRef = spy.interface('ChangeDetector', ['markForCheck'])
     pipe = new CanPipe(ability, changeDetectorRef)
   })

packages/casl-angular/spec/module.spec.js

@@ -1,4 +1,4 @@
-import { Ability } from '@casl/ability'
+import { PureAbility, Ability } from '@casl/ability'
 import { TestBed } from '@angular/core/testing'
 import { AbilityModule } from '../dist/es6'
 import { App, Post } from './spec_helper'
@@ -8,25 +8,29 @@ describe('Ability', () => {
 
   beforeEach(() => {
     TestBed.configureTestingModule({
-      imports: [AbilityModule.forRoot()],
+      imports: [AbilityModule],
       declarations: [App],
+      providers: [
+        { provide: PureAbility, useFactory: () => new Ability() }
+      ]
     })
   })
 
-  describe('module', () => {
-    it('provides empty `Ability` instance', () => {
-      const ability = TestBed.inject(Ability)
-
-      expect(ability).to.be.instanceof(Ability)
-      expect(ability.rules).to.be.empty
-    })
+  afterEach(() => {
+    if (fixture) {
+      fixture.destroy()
+    }
+  })
 
+  describe('module', () => {
     it('provides `can` pipe', () => {
       fixture = createComponent(App)
-
       expect(fixture.nativeElement.textContent).to.equal('false')
+    })
 
-      fixture.destroy()
+    it('provides `able` pipe', () => {
+      fixture = createComponent(App, { pipe: 'able' })
+      expect(fixture.nativeElement.textContent).to.equal('false')
     })
   })
 
@@ -35,14 +39,10 @@ describe('Ability', () => {
     let post
 
     beforeEach(() => {
-      ability = TestBed.inject(Ability)
+      ability = TestBed.inject(PureAbility)
       post = new Post({ author: 'me' })
     })
 
-    afterEach(() => {
-      fixture.destroy()
-    })
-
     it('updates template when `ability` is updated', () => {
       fixture = createComponent(App, { post })
       ability.update([{ subject: Post.name, action: 'read' }])

packages/casl-angular/spec/spec_helper.js

@@ -21,8 +21,8 @@ export class App {
     return [
       new Component({
         selector: 'app-ability',
-        template: '{{ "read" | able: post }}',
-        inputs: ['post']
+        template: '{{ pipe === "able" ? ("read" | able: post) : (post | can: "read") }}',
+        inputs: ['post', 'pipe']
       })
     ]
   }

packages/casl-angular/src/can.ts

@@ -1,5 +1,5 @@
 import { Pipe, ChangeDetectorRef, Inject } from '@angular/core';
-import { Ability, Unsubscribe, AnyAbility, AbilityParameters } from '@casl/ability';
+import { PureAbility, Unsubscribe, AnyAbility, AbilityParameters } from '@casl/ability';
 
 class AbilityPipe<T extends AnyAbility> {
   protected _unsubscribeFromAbility?: Unsubscribe;
@@ -30,7 +30,7 @@ class AbilityPipe<T extends AnyAbility> {
 export class CanPipe<T extends AnyAbility> {
   protected pipe: AbilityPipe<T>;
 
-  constructor(@Inject(Ability) ability: T, cd: ChangeDetectorRef) {
+  constructor(@Inject(PureAbility) ability: T, cd: ChangeDetectorRef) {
     this.pipe = new AbilityPipe(ability, cd);
   }
 
@@ -51,7 +51,7 @@ export class CanPipe<T extends AnyAbility> {
 export class AblePipe<T extends AnyAbility> {
   protected pipe: AbilityPipe<T>;
 
-  constructor(@Inject(Ability) ability: T, cd: ChangeDetectorRef) {
+  constructor(@Inject(PureAbility) ability: T, cd: ChangeDetectorRef) {
     this.pipe = new AbilityPipe(ability, cd);
   }
 

packages/casl-angular/src/module.ts

@@ -1,5 +1,4 @@
-import { NgModule, ModuleWithProviders } from '@angular/core';
-import { Ability, AnyAbility } from '@casl/ability';
+import { NgModule } from '@angular/core';
 import { CanPipe, AblePipe } from './can';
 
 @NgModule({
@@ -13,15 +12,4 @@ import { CanPipe, AblePipe } from './can';
   ],
 })
 export class AbilityModule {
-  static forRoot<T extends AnyAbility>(): ModuleWithProviders<AbilityModule> {
-    return {
-      ngModule: AbilityModule,
-      providers: [
-        {
-          provide: Ability,
-          useFactory: () => (new Ability([]) as T)
-        },
-      ]
-    };
-  }
 }