refactor: move angular source to /packages rather than modules/@angular

packages/compiler/src/pipe_resolver.ts

@@ -0,0 +1,49 @@
+/**
+ * @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 {Pipe, Type, resolveForwardRef, ɵReflectorReader, ɵreflector, ɵstringify as stringify} from '@angular/core';
+import {findLast} from './directive_resolver';
+import {CompilerInjectable} from './injectable';
+
+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}
+ */
+@CompilerInjectable()
+export class PipeResolver {
+  constructor(private _reflector: ɵReflectorReader = ɵreflector) {}
+
+  isPipe(type: Type<any>) {
+    const typeMetadata = this._reflector.annotations(resolveForwardRef(type));
+    return typeMetadata && typeMetadata.some(_isPipeMetadata);
+  }
+
+  /**
+   * Return {@link Pipe} for a given `Type`.
+   */
+  resolve(type: Type<any>, throwIfNotFound = true): Pipe {
+    const metas = this._reflector.annotations(resolveForwardRef(type));
+    if (metas) {
+      const annotation = findLast(metas, _isPipeMetadata);
+      if (annotation) {
+        return annotation;
+      }
+    }
+    if (throwIfNotFound) {
+      throw new Error(`No Pipe decorator found on ${stringify(type)}`);
+    }
+    return null;
+  }
+}