Files
angular/modules/@angular/compiler/src/pipe_resolver.ts
Tobias Bosch 63e15ffaec refactor(core): remove …Metadata for all decorators and use the decorator directly.
BREAKING CHANGE:
- all `…Metadata` classes have been removed. Use the corresponding decorator
  as constructor or for `instanceof` checks instead.
- Example:
  * Before: `new ComponentMetadata(…)`
  * After: `new Component(…)`
- Note: `new Component(…)` worked before as well.
2016-09-12 22:47:54 -07:00

46 lines
1.2 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 {Injectable, Pipe, Type, resolveForwardRef} from '@angular/core';
import {isPresent, stringify} from './facade/lang';
import {ReflectorReader, reflector} from './private_import_core';
function _isPipeMetadata(type: any): boolean {
return type instanceof Pipe;
}
/**
* Resolve a `Type` for {@link Pipe}.
*
* This interface can be overridden by the application developer to create custom behavior.
*
* See {@link Compiler}
*/
@Injectable()
export class PipeResolver {
constructor(private _reflector: ReflectorReader = reflector) {}
/**
* Return {@link Pipe} for a given `Type`.
*/
resolve(type: Type<any>, throwIfNotFound = true): Pipe {
var metas = this._reflector.annotations(resolveForwardRef(type));
if (isPresent(metas)) {
var annotation = metas.find(_isPipeMetadata);
if (isPresent(annotation)) {
return annotation;
}
}
if (throwIfNotFound) {
throw new Error(`No Pipe decorator found on ${stringify(type)}`);
}
return null;
}
}