Cannot read property 'properties' of undefined when adding a lazy loaded module with ng generate

🐞 Bug report

Command (mark with an x)

• new
• build
• serve
• test
• e2e
• generate
• add
• update
• lint
• extract-i18n
• run
• config
• help
• version
• doc

Description

While attempting to find the module to add a lazy loaded route declaration to while generating a new lazy loaded module with option --module=app, findModuleFromOptions tries file candidates from least to most specific:

[
  '/src/app/areas',
  '/src/app/areas/app.ts',
  '/src/app/areas/app.module.ts'
]

If both app.module.ts and app.ts exist, app.ts is returned. If that file does not include an @angular/core import, this leads to an Cannot read property 'properties' of undefined error down the line (node is undefined in getMetadataField in ast-utils).

🔬 Minimal Reproduction

• Create a new angular project using ng new.
• Create an empty file src/app/app.ts
• Call ng g m foo --routing --route=foo --module=app

🔥 Exception or Error

Cannot read property 'properties' of undefined

🌍 Your Environment

Angular CLI: 12.1.3
Node: 12.18.3
Package Manager: npm 6.14.6
OS: win32 x64

Angular: 12.1.3
... animations, cli, common, compiler, compiler-cli, core, forms
... platform-browser, platform-browser-dynamic, router

Package                         Version
---------------------------------------------------------
@angular-devkit/architect       0.1201.3
@angular-devkit/build-angular   12.1.3
@angular-devkit/core            12.1.3
@angular-devkit/schematics      12.1.3
@schematics/angular             12.1.3
rxjs                            6.6.7
typescript                      4.3.5

Workaround

To work around this issue, we can specify the module by file name, not module name:

ng g m foo --routing --route=foo --module=app.module.ts

[kuldeepvishwakarma05]

Angular CLI: 12.1.3 Node: 12.18.3 Package Manager: npm 6.14.6 OS: win32 x64

Angular: 12.1.3 … animations, cli, common, compiler, compiler-cli, core, forms … platform-browser, platform-browser-dynamic, router

Package Version

@angular-devkit/architect 0.1201.3 @angular-devkit/build-angular 12.1.3 @angular-devkit/core 12.1.3 @angular-devkit/schematics 12.1.3 @schematics/angular 12.1.3 rxjs 6.6.7 typescript 4.3.5

[tejas10191]

@alan-agius4 Ideally, it should skip the file-path without module.ts extension ?