Alex Rickabaugh 235a235fab feat: change @Injectable() to support tree-shakeable tokens (#22005)
This commit bundles 3 important changes, with the goal of enabling tree-shaking
of services which are never injected. Ordinarily, this tree-shaking is prevented
by the existence of a hard dependency on the service by the module in which it
is declared.

Firstly, @Injectable() is modified to accept a 'scope' parameter, which points
to an @NgModule(). This reverses the dependency edge, permitting the module to
not depend on the service which it "provides".

Secondly, the runtime is modified to understand the new relationship created
above. When a module receives a request to inject a token, and cannot find that
token in its list of providers, it will then look at the token for a special
ngInjectableDef field which indicates which module the token is scoped to. If
that module happens to be in the injector, it will behave as if the token
itself was in the injector to begin with.

Thirdly, the compiler is modified to read the @Injectable() metadata and to
generate the special ngInjectableDef field as part of TS compilation, using the
PartialModules system.

Additionally, this commit adds several unit and integration tests of various
flavors to test this change.

PR Close #22005
2018-02-12 14:34:59 -08:00

90 lines
2.7 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 {syntaxError} from '@angular/compiler';
import * as path from 'path';
import * as ts from 'typescript';
import {CompilerOptions, DEFAULT_ERROR_CODE, Diagnostic, SOURCE} from './api';
export const GENERATED_FILES = /(.*?)\.(ngfactory|shim\.ngstyle|ngstyle|ngsummary)\.(js|d\.ts|ts)$/;
export const DTS = /\.d\.ts$/;
export const TS = /^(?!.*\.d\.ts$).*\.ts$/;
export const enum StructureIsReused {Not = 0, SafeModules = 1, Completely = 2}
// Note: This is an internal property in TypeScript. Use it only for assertions and tests.
export function tsStructureIsReused(program: ts.Program): StructureIsReused {
return (program as any).structureIsReused;
}
export function error(msg: string): never {
throw new Error(`Internal error: ${msg}`);
}
export function userError(msg: string): never {
throw syntaxError(msg);
}
export function createMessageDiagnostic(messageText: string): ts.Diagnostic&Diagnostic {
return {
file: undefined,
start: undefined,
length: undefined,
category: ts.DiagnosticCategory.Message, messageText,
code: DEFAULT_ERROR_CODE,
source: SOURCE,
};
}
export function isInRootDir(fileName: string, options: CompilerOptions) {
return !options.rootDir || pathStartsWithPrefix(options.rootDir, fileName);
}
export function relativeToRootDirs(filePath: string, rootDirs: string[]): string {
if (!filePath) return filePath;
for (const dir of rootDirs || []) {
const rel = pathStartsWithPrefix(dir, filePath);
if (rel) {
return rel;
}
}
return filePath;
}
function pathStartsWithPrefix(prefix: string, fullPath: string): string|null {
const rel = path.relative(prefix, fullPath);
return rel.startsWith('..') ? null : rel;
}
/**
* Converts a ng.Diagnostic into a ts.Diagnostic.
* This looses some information, and also uses an incomplete object as `file`.
*
* I.e. only use this where the API allows only a ts.Diagnostic.
*/
export function ngToTsDiagnostic(ng: Diagnostic): ts.Diagnostic {
let file: ts.SourceFile|undefined;
let start: number|undefined;
let length: number|undefined;
if (ng.span) {
// Note: We can't use a real ts.SourceFile,
// but we can at least mirror the properties `fileName` and `text`, which
// are mostly used for error reporting.
file = { fileName: ng.span.start.file.url, text: ng.span.start.file.content } as ts.SourceFile;
start = ng.span.start.offset;
length = ng.span.end.offset - start;
}
return {
file,
messageText: ng.messageText,
category: ng.category,
code: ng.code, start, length,
};
}