2018-08-14 11:58:47 -07:00

74 lines
2.1 KiB
TypeScript

/**
* @license
* Copyright Google Inc. All Rights Reserved.
*
* Use of this source code is governed by an MIT-style license that can be
* found in the LICENSE file at https://angular.io/license
*/
import {Component, Directive, NgModule, Pipe, Type, ɵReflectionCapabilities as ReflectionCapabilities} from '@angular/core';
import {MetadataOverride} from './metadata_override';
import {MetadataOverrider} from './metadata_overrider';
const reflection = new ReflectionCapabilities();
/**
* Base interface to resolve `@Component`, `@Directive`, `@Pipe` and `@NgModule`.
*/
export interface Resolver<T> { resolve(type: Type<any>): T|null; }
/**
* Allows to override ivy metadata for tests (via the `TestBed`).
*/
abstract class OverrideResolver<T> implements Resolver<T> {
private overrides = new Map<Type<any>, MetadataOverride<T>>();
private resolved = new Map<Type<any>, T|null>();
abstract get type(): any;
setOverrides(overrides: Array<[Type<any>, MetadataOverride<T>]>) {
this.overrides.clear();
overrides.forEach(([type, override]) => this.overrides.set(type, override));
}
getAnnotation(type: Type<any>): T|null {
return reflection.annotations(type).find(a => a instanceof this.type) || null;
}
resolve(type: Type<any>): T|null {
let resolved = this.resolved.get(type) || null;
if (!resolved) {
resolved = this.getAnnotation(type);
if (resolved) {
const override = this.overrides.get(type);
if (override) {
const overrider = new MetadataOverrider();
resolved = overrider.overrideMetadata(this.type, resolved, override);
}
}
this.resolved.set(type, resolved);
}
return resolved;
}
}
export class DirectiveResolver extends OverrideResolver<Directive> {
get type() { return Directive; }
}
export class ComponentResolver extends OverrideResolver<Component> {
get type() { return Component; }
}
export class PipeResolver extends OverrideResolver<Pipe> {
get type() { return Pipe; }
}
export class NgModuleResolver extends OverrideResolver<NgModule> {
get type() { return NgModule; }
}