angular-docs-cn/packages/language-service/test/diagnostics_spec.ts

/**
 * @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 * as ts from 'typescript';

import {createLanguageService} from '../src/language_service';
import {Diagnostics, LanguageService} from '../src/types';
import {TypeScriptServiceHost} from '../src/typescript_host';

import {toh} from './test_data';
import {MockTypescriptHost, diagnosticMessageContains, findDiagnostic, includeDiagnostic, noDiagnostics} from './test_utils';

describe('diagnostics', () => {
  let mockHost: MockTypescriptHost;
  let ngHost: TypeScriptServiceHost;
  let ngService: LanguageService;

  beforeEach(() => {
    mockHost = new MockTypescriptHost(['/app/main.ts', '/app/parsing-cases.ts'], toh);
    const documentRegistry = ts.createDocumentRegistry();
    const service = ts.createLanguageService(mockHost, documentRegistry);
    ngHost = new TypeScriptServiceHost(mockHost, service);
    ngService = createLanguageService(ngHost);
    ngHost.setSite(ngService);
  });

  it('should be no diagnostics for test.ng',
     () => { expect(ngService.getDiagnostics('/app/test.ng')).toEqual([]); });

  describe('for semantic errors', () => {
    const fileName = '/app/test.ng';

    function diagnostics(template: string): Diagnostics {
      try {
        mockHost.override(fileName, template);
        return ngService.getDiagnostics(fileName) !;
      } finally {
        mockHost.override(fileName, undefined !);
      }
    }

    function accept(template: string) { noDiagnostics(diagnostics(template)); }

    function reject(template: string, message: string): void;
    function reject(template: string, message: string, at: string): void;
    function reject(template: string, message: string, location: string): void;
    function reject(template: string, message: string, location: string, len: number): void;
    function reject(template: string, message: string, at?: number | string, len?: number): void {
      if (typeof at == 'string') {
        len = at.length;
        at = template.indexOf(at);
      }
      includeDiagnostic(diagnostics(template), message, at, len);
    }

    describe('regression', () => {
      it('should be able to return diagnostics if reflector gets invalidated', () => {
        const fileName = '/app/main.ts';
        ngService.getDiagnostics(fileName);
        (ngHost as any)._reflector = null;
        ngService.getDiagnostics(fileName);
      });

      // #17611
      it('should not report diagnostic on iteration of any',
         () => { accept('<div *ngFor="let value of anyValue">{{value.someField}}</div>'); });
    });

    describe('with $event', () => {
      it('should accept an event',
         () => { accept('<div (click)="myClick($event)">Click me!</div>'); });
      it('should reject it when not in an event binding', () => {
        reject('<div [tabIndex]="$event"></div>', '\'$event\' is not defined', '$event');
      });
    });
  });

  describe('with regression tests', () => {

    it('should not crash with a incomplete *ngFor', () => {
      expect(() => {
        const code =
            '\n@Component({template: \'<div *ngFor></div> ~{after-div}\'}) export class MyComponent {}';
        addCode(code, fileName => { ngService.getDiagnostics(fileName); });
      }).not.toThrow();
    });

    it('should report a component not in a module', () => {
      const code = '\n@Component({template: \'<div></div>\'}) export class MyComponent {}';
      addCode(code, (fileName, content) => {
        const diagnostics = ngService.getDiagnostics(fileName);
        const offset = content !.lastIndexOf('@Component') + 1;
        const len = 'Component'.length;
        includeDiagnostic(
            diagnostics !, 'Component \'MyComponent\' is not included in a module', offset, len);
      });
    });

    it('should not report an error for a form\'s host directives', () => {
      const code = '\n@Component({template: \'<form></form>\'}) export class MyComponent {}';
      addCode(code, (fileName, content) => {
        const diagnostics = ngService.getDiagnostics(fileName);
        expectOnlyModuleDiagnostics(diagnostics);
      });
    });

    it('should not throw getting diagnostics for an index expression', () => {
      const code =
          ` @Component({template: '<a *ngIf="(auth.isAdmin | async) || (event.leads && event.leads[(auth.uid | async)])"></a>'}) export class MyComponent {}`;
      addCode(
          code, fileName => { expect(() => ngService.getDiagnostics(fileName)).not.toThrow(); });
    });

    it('should not throw using a directive with no value', () => {
      const code =
          ` @Component({template: '<form><input [(ngModel)]="name" required /></form>'}) export class MyComponent { name = 'some name'; }`;
      addCode(
          code, fileName => { expect(() => ngService.getDiagnostics(fileName)).not.toThrow(); });
    });

    it('should report an error for invalid metadata', () => {
      const code =
          ` @Component({template: '', provider: [{provide: 'foo', useFactor: () => 'foo' }]}) export class MyComponent { name = 'some name'; }`;
      addCode(code, (fileName, content) => {
        const diagnostics = ngService.getDiagnostics(fileName);
        includeDiagnostic(
            diagnostics !, 'Function expressions are not supported in decorators', '() => \'foo\'',
            content);
      });
    });

    it('should not throw for an invalid class', () => {
      const code = ` @Component({template: ''}) class`;
      addCode(
          code, fileName => { expect(() => ngService.getDiagnostics(fileName)).not.toThrow(); });
    });

    it('should not report an error for sub-types of string', () => {
      const code =
          ` @Component({template: \`<div *ngIf="something === 'foo'"></div>\`}) export class MyComponent { something: 'foo' | 'bar'; }`;
      addCode(code, fileName => {
        const diagnostics = ngService.getDiagnostics(fileName);
        expectOnlyModuleDiagnostics(diagnostics);
      });
    });

    it('should report a warning if an event results in a callable expression', () => {
      const code =
          ` @Component({template: \`<div (click)="onClick"></div>\`}) export class MyComponent { onClick() { } }`;
      addCode(code, (fileName, content) => {
        const diagnostics = ngService.getDiagnostics(fileName);
        includeDiagnostic(
            diagnostics !, 'Unexpected callable expression. Expected a method call', 'onClick',
            content);
      });
    });

    // #13412
    it('should not report an error for using undefined', () => {
      const code =
          ` @Component({template: \`<div *ngIf="something === undefined"></div>\`}) export class MyComponent { something = 'foo'; }})`;
      addCode(code, fileName => {
        const diagnostics = ngService.getDiagnostics(fileName);
        expectOnlyModuleDiagnostics(diagnostics);
      });
    });

    // Issue #13326
    it('should report a narrow span for invalid pipes', () => {
      const code =
          ` @Component({template: '<p> Using an invalid pipe {{data | dat}} </p>'}) export class MyComponent { data = 'some data'; }`;
      addCode(code, fileName => {
        const diagnostic = findDiagnostic(ngService.getDiagnostics(fileName) !, 'pipe') !;
        expect(diagnostic).not.toBeUndefined();
        expect(diagnostic.span.end - diagnostic.span.start).toBeLessThan(11);
      });
    });

    // Issue #19406
    it('should allow empty template', () => {
      const appComponent = `
        import { Component } from '@angular/core';

        @Component({
          template : '',
        })
        export class AppComponent {}
      `;
      const fileName = '/app/app.component.ts';
      mockHost.override(fileName, appComponent);
      const diagnostics = ngService.getDiagnostics(fileName);
      expect(diagnostics).toEqual([]);
    });

    // Issue #15460
    it('should be able to find members defined on an ancestor type', () => {
      const app_component = `
        import { Component } from '@angular/core';
        import { NgForm } from '@angular/common';

        @Component({
          selector: 'example-app',
          template: \`
             <form #f="ngForm" (ngSubmit)="onSubmit(f)" novalidate>
              <input name="first" ngModel required #first="ngModel">
              <input name="last" ngModel>
              <button>Submit</button>
            </form>
            <p>First name value: {{ first.value }}</p>
            <p>First name valid: {{ first.valid }}</p>
            <p>Form value: {{ f.value | json }}</p>
            <p>Form valid: {{ f.valid }}</p>
         \`,
        })
        export class AppComponent {
          onSubmit(form: NgForm) {}
        }
      `;
      const fileName = '/app/app.component.ts';
      mockHost.override(fileName, app_component);
      const diagnostic = ngService.getDiagnostics(fileName);
      expect(diagnostic).toEqual([]);
    });

    it('should report an error for invalid providers', () => {
      addCode(
          `
        @Component({
          template: '',
          providers: [null]
       })
       export class MyComponent {}
      `,
          fileName => {
            const diagnostics = ngService.getDiagnostics(fileName) !;
            const expected = findDiagnostic(diagnostics, 'Invalid providers for');
            const notExpected = findDiagnostic(diagnostics, 'Cannot read property');
            expect(expected).toBeDefined();
            expect(notExpected).toBeUndefined();
          });
    });

    // Issue #15768
    it('should be able to parse a template reference', () => {
      addCode(
          `
        @Component({
          selector: 'my-component',
          template: \`
            <div *ngIf="comps | async; let comps; else loading">
            </div>
            <ng-template #loading>Loading comps...</ng-template>
          \`
        })
        export class MyComponent {}
      `,
          fileName => expectOnlyModuleDiagnostics(ngService.getDiagnostics(fileName)));
    });

    // Issue #15625
    it('should not report errors for localization syntax', () => {
      addCode(
          `
          @Component({
            selector: 'my-component',
            template: \`
            <div>
                {fieldCount, plural, =0 {no fields} =1 {1 field} other {{{fieldCount}} fields}}
            </div>
            \`
          })
          export class MyComponent {
            fieldCount: number;
          }
      `,
          fileName => {
            const diagnostics = ngService.getDiagnostics(fileName);
            expectOnlyModuleDiagnostics(diagnostics);
          });
    });

    // Issue #15885
    it('should be able to remove null and undefined from a type', () => {
      mockHost.overrideOptions(options => {
        options.strictNullChecks = true;
        return options;
      });
      addCode(
          `
        @Component({
          selector: 'my-component',
          template: \` {{test?.a}}
          \`
        })
        export class MyComponent {
          test: {a: number, b: number} | null = {
            a: 1,
            b: 2
          };
        }
      `,
          fileName => expectOnlyModuleDiagnostics(ngService.getDiagnostics(fileName)));
    });

    it('should be able to resolve modules using baseUrl', () => {
      const app_component = `
        import { Component } from '@angular/core';
        import { NgForm } from '@angular/common';
        import { Server } from 'app/server';

        @Component({
          selector: 'example-app',
          template: '...',
          providers: [Server]
        })
        export class AppComponent {
          onSubmit(form: NgForm) {}
        }
      `;
      const app_server = `
        export class Server {}
      `;
      const fileName = '/app/app.component.ts';
      mockHost.override(fileName, app_component);
      mockHost.addScript('/other/files/app/server.ts', app_server);
      mockHost.overrideOptions(options => {
        options.baseUrl = '/other/files';
        return options;
      });
      const diagnostic = ngService.getDiagnostics(fileName);
      expect(diagnostic).toEqual([]);
    });

    it('should not report errors for using the now removed OpaqueToken (support for v4)', () => {
      const app_component = `
        import { Component, Inject, OpaqueToken } from '@angular/core';
        import { NgForm } from '@angular/common';

        export const token = new OpaqueToken();

        @Component({
          selector: 'example-app',
          template: '...'
        })
        export class AppComponent {
          constructor (@Inject(token) value: string) {}
          onSubmit(form: NgForm) {}
        }
      `;
      const fileName = '/app/app.component.ts';
      mockHost.override(fileName, app_component);
      const diagnostics = ngService.getDiagnostics(fileName);
      expect(diagnostics).toEqual([]);
    });

    function addCode(code: string, cb: (fileName: string, content?: string) => void) {
      const fileName = '/app/app.component.ts';
      const originalContent = mockHost.getFileContent(fileName);
      const newContent = originalContent + code;
      mockHost.override(fileName, originalContent + code);
      ngHost.updateAnalyzedModules();
      try {
        cb(fileName, newContent);
      } finally {
        mockHost.override(fileName, undefined !);
      }
    }

    function expectOnlyModuleDiagnostics(diagnostics: Diagnostics | undefined) {
      // Expect only the 'MyComponent' diagnostic
      if (!diagnostics) throw new Error('Expecting Diagnostics');
      if (diagnostics.length > 1) {
        const unexpectedDiagnostics =
            diagnostics.filter(diag => !diagnosticMessageContains(diag.message, 'MyComponent'))
                .map(diag => `(${diag.span.start}:${diag.span.end}): ${diag.message}`);

        if (unexpectedDiagnostics.length) {
          fail(`Unexpected diagnostics:\n  ${unexpectedDiagnostics.join('\n  ')}`);
          return;
        }
      }
      expect(diagnostics.length).toBe(1);
      expect(diagnosticMessageContains(diagnostics[0].message, 'MyComponent')).toBeTruthy();
    }
  });
});