[CLI][Schematics] Override Angular Schematics issue - no way to determine which arguments were provided by the user and which ones by the CLI parser

[SlawomiKussowski]

Command

generate

Is this a regression?

• Yes, this behavior used to work in the previous version

The previous version in which this bug was not present was

Unknown

Description

If you try to override standard Angular Schematics with a custom one by the use of schematicCollections option in angular.json file like for instance:

"cli": { "analytics": false, "schematicCollections": [ "./schematics", "@schematics/angular" ] }

And create your custom schematics (index.ts):

export function generateComponent(options: ComponentOptions): Rule {
  console.log('options', structuredClone(options));
  return (_tree: Tree, _context: SchematicContext) => {
    return externalSchematic(
      "@schematics/angular",
      "component",
      options
    );
  };
}

And define custom defaults using angular.json file, like for instance:

  "cli": {
    "analytics": false,
    "schematicCollections": [
      "./schematics",
      "@schematics/angular"
    ]
  },
    "schematics": {
    "@schematics/angular:component": {
      "inlineTemplate": false,
      "inlineStyle": false,
      "style": "scss",
      "skipTests": true
    }
  }

You will notice that your defaults are ignored.

Moreover, in options argument from generateComponent function the values are already parsed by the cli making it impossible to distinguish which ones were provided by the user and which ones by the parser.

Minimal Reproduction

Please use the attached repo to reproduce the issue:

Execute schematics:

ng g c test

Options values received in generateComponent function:

options {
  name: 'test',
  path: undefined,
  project: 'schematics-test',
  displayBlock: false,
  inlineStyle: false,
  inlineTemplate: false,
  standalone: true,
  viewEncapsulation: undefined,
  changeDetection: 'Default',
  prefix: undefined,
  style: 'css',
  type: 'Component',
  skipTests: false,
  flat: false,
  skipImport: false,
  selector: undefined,
  skipSelector: false,
  module: undefined,
  export: false,
  exportDefault: false
}

Exception or Error

Your Environment

Angular CLI: 19.2.5
Node: 22.13.0
Package Manager: npm 8.6.0
OS: win32 x64

Angular: 19.2.4
... animations, common, compiler, compiler-cli, core, forms
... platform-browser, platform-browser-dynamic, router

Package                         Version
---------------------------------------------------------
@angular-devkit/architect       0.1902.5
@angular-devkit/build-angular   19.2.5
@angular-devkit/core            19.2.5
@angular-devkit/schematics      19.2.5
@angular/cli                    19.2.5
@schematics/angular             19.2.5
rxjs                            7.8.1
typescript                      5.7.3
zone.js                         0.15.0

Anything else relevant?

No response

[SlawomiKussowski]

Please use the attached repo to reproduce the issue:

schematics-test.zip

[alan-agius4]

This behavior is expected. The custom schematic is using the schema from @schematics/angular, and when invoked, it applies the default options to ./schematics:component, which are then passed down to @schematics/angular.

In angular.json, instead of using @schematics/angular:component, you should specify ./schematics:component.

[SlawomiKussowski]

Thank you for the explanation. In case I am calling the ng command from a root folder it indeed worked.
However, in case I go to any subfolder in my project, calling ng generate... ends up with an error. I created a dedicated issue for this: #29978