bug(cdk): Update Failed : Cannot read property 'length' of null

[filol]

Reproduction

I can't share my code because it's a big project, hope the stack will help you
ng update @angular/material --force

Expected Behavior

Working

Actual Behavior

 ** Executing migrations for package '@angular/cdk' **
Cannot read property 'length' of null

Stack trace in log file :

[error] TypeError: Cannot read property 'length' of null
    at Object.computeLineStartsMap (path\node_modules\@angular\cdk\schematics\update-tool\utils\line-mappings.js:39:23)
    at ComponentResourceCollector.resolveExternalStylesheet (path\node_modules\@angular\cdk\schematics\update-tool\component-resource-collector.js:131:47)
    at path\node_modules\@angular\cdk\schematics\update-tool\index.js:97:50
    at Array.forEach (<anonymous>)
    at UpdateProject.migrate (path\node_modules\@angular\cdk\schematics\update-tool\index.js:95:35)
    at runMigrations (path\node_modules\@angular\cdk\schematics\ng-update\devkit-migration-rule.js:128:42)
    at Object.<anonymous> (path\node_modules\@angular\cdk\schematics\ng-update\devkit-migration-rule.js:83:17)
    at Generator.next (<anonymous>)
    at path\node_modules\@angular\cdk\schematics\ng-update\devkit-migration-rule.js:15:71
    at new Promise (<anonymous>)
    at __awaiter (path\node_modules\@angular\cdk\schematics\ng-update\devkit-migration-rule.js:11:12)
    at path\node_modules\@angular\cdk\schematics\ng-update\devkit-migration-rule.js:57:31
    at MergeMapSubscriber.project (path\node_modules\@angular-devkit\schematics\src\rules\call.js:75:24)
    at MergeMapSubscriber._tryNext (path\node_modules\rxjs\internal\operators\mergeMap.js:69:27)
    at MergeMapSubscriber._next (path\node_modules\rxjs\internal\operators\mergeMap.js:59:18)
    at MergeMapSubscriber.Subscriber.next (path\node_modules\rxjs\internal\Subscriber.js:66:18)

Environment

     _                      _                 ____ _     ___
    / \   _ __   __ _ _   _| | __ _ _ __     / ___| |   |_ _|
   / △ \ | '_ \ / _` | | | | |/ _` | '__|   | |   | |    | |
  / ___ \| | | | (_| | |_| | | (_| | |      | |___| |___ | |
 /_/   \_\_| |_|\__, |\__,_|_|\__,_|_|       \____|_____|___|
                |___/
    

Angular CLI: 10.0.0
Node: 12.4.0
OS: win32 x64

Angular: 10.0.0
... animations, cdk, cli, common, compiler, compiler-cli, core
... forms, language-service, material, platform-browser
... platform-browser-dynamic, router
Ivy Workspace: Yes

Package                           Version
-----------------------------------------------------------
@angular-devkit/architect         0.1000.0
@angular-devkit/build-angular     0.1000.0
@angular-devkit/build-optimizer   0.1000.0
@angular-devkit/build-webpack     0.1000.0
@angular-devkit/core              10.0.0
@angular-devkit/schematics        10.0.0
@angular/flex-layout              10.0.0-beta.32
@ngtools/webpack                  10.0.0
@schematics/angular               9.1.9
@schematics/update                0.1000.0
rxjs                              6.5.5
typescript                        3.9.5
webpack                           4.43.0

• Operating System (e.g. Windows, macOS, Ubuntu): Windows 10

[devversion]

@filol Thanks for this issue! Do you know if you have any files in your project that are not readable? or in better terms which might have permission issues? We have a fix for this in progress, but we'd like to understand how this issue surfaces on your end.

If possible, it would be great to have the requested information above, and potentially when you get a chance, it might be helpful if you manually modify the resolveExternalStylesheet function and log/debug the file path. That would be awesome.

If that's not possible (due to the incremental nature of ng update), let me know. Not a big deal. Thanks!

[filol]

@devversion @crisbeto I checked I have all the rights, I even closed my IDE, launched the console in administrator mode and it is exactly the same error.

I'm not sure I understood the "requested information above" of your message.

I have manually log the path, the error is throw on the first path :

Repository is not clean. Update changes will be mixed with pre-existing changes.
Using package manager: 'yarn'
Collecting installed dependencies...
Found 59 dependencies.
** Executing migrations of package '@angular/material' **

> Updates Angular Material to v10
Path : components/business/appels-d-offres/appels-d-offres.component.scss
× Migration failed: Cannot read property 'length' of null
  See "C:\Users\FRANOI~1\AppData\Local\Temp\ng-SlLOJo\angular-errors.log" for further details.

If you want i can provide you this file but it's really basic

[devversion]

@filol Thanks! yeah, with information above I actually just referred to the "permission issues". Thanks for checking that.

Does your project have the file components/business/appels-d-offres/appels-d-offres.component.scss? It would be interesting to see if the components folder is directly at same level with the angular.json file. Can you please check that? That would be all.