TypeScript compiler in Gulp says it cannot find @angular modules but compiles fine

Question

I'm getting a lot of "false" errors when my gulp task compiles my typescript. Here's the relevant gulp task:

var tsProject = typescript.createProject('tsconfig.json', {noResolve: true});

gulp.task('build-ts', function() {
    gulp.src(appDev + '**/*.ts')
        .pipe(sourcemaps.init())
        .pipe(typescript(tsProject))
        .pipe(sourcemaps.write())
        //.pipe(jsuglify())
        .pipe(gulp.dest(appProd));
    gulp.src(appDev + '**/*.+(html|css)')
        .pipe(gulp.dest(appProd));
});

And these are the errors I get:

[09:38:52] Starting 'default'...
[09:38:52] Finished 'default' after 8.88 ms
ng/app.component.ts(1,27): error TS2307: Cannot find module '@angular/core'.
ng/app.component.ts(5,12): error TS2304: Cannot find name 'module'.
ng/app.module.ts(1,26): error TS2307: Cannot find module '@angular/core'.
ng/app.module.ts(2,31): error TS2307: Cannot find module '@angular/platform-browser'.
ng/app.module.ts(3,31): error TS2307: Cannot find module '@angular/common'.
[...]
[09:38:53] TypeScript: 27 semantic errors
[09:38:53] TypeScript: emit succeeded (with errors)
[BS] Proxying: http://0.0.0.0:5000

My tree structure looks like this (simplified):

.
├── gulpfile.js
├── ng
├── node_modules
├── package.json
├── tsconfig.json
├── typings.json
└── web

All the modules that the Typescript compiler fails to find are actually in node_modules and my final application works fine despite all the errors.

This is my tsconfig.js:

{
  "compilerOptions": {
    "target": "ES5",
    "module": "commonjs",
    "moduleResolution": "node",
    "sourceMap": true,
    "emitDecoratorMetadata": true,
    "experimentalDecorators": true,
    "removeComments": false,
    "noImplicitAny": false,
    "outDir": "./app"
  },
  "filesGlob": [
    "./app/**/*.ts",
    "!./node_modules/**/*.ts"
  ],
  "exclude": [
    "node_modules",
    "typings/main",
    "typings/main.d.ts"
  ],
  "atom": {
    "rewriteTsconfig": true
  }
}

How can I get rid of these "false positive" errors.

Answer 1

In the gulp.js file the line

var tsProject = typescript.createProject('tsconfig.json', {noExternalResolve: true, noResolve: true});

should be

var tsProject = typescript.createProject('tsconfig.json');

As we want to load external typings.

And also you need to load the typings in the main.ts file on the top :

/// <reference path="../typings/index.d.ts" />

I did clone your project and it compiles without warnings after this.