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bug(cdk/a11y): Observable in HighContrastModeDetector constructor is undefined

See original GitHub issue

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

14.0.1

Description

Caused by #25088

This line fails during Karma testing because the observe call before it returns undefined

Stack trace:

    TypeError: Cannot read properties of undefined (reading 'subscribe')
        at new HighContrastModeDetector (node_modules/@angular/cdk/fesm2020/a11y.mjs:2348:40)
        at Object.factory (node_modules/@angular/cdk/fesm2020/a11y.mjs:2406:1)
        at R3Injector.hydrate (node_modules/@angular/core/fesm2020/core.mjs:9258:35)
        at R3Injector.get (node_modules/@angular/core/fesm2020/core.mjs:9146:33)
        at injectInjectorOnly (node_modules/@angular/core/fesm2020/core.mjs:4778:33)
        at Module.ɵɵinject (node_modules/@angular/core/fesm2020/core.mjs:4782:12)
        at Object.useFactory (node_modules/@angular/material/fesm2020/core.mjs:105:1)
        at Object.factory (node_modules/@angular/core/fesm2020/core.mjs:9345:38)
        at R3Injector.hydrate (node_modules/@angular/core/fesm2020/core.mjs:9258:35)
        at R3Injector.get (node_modules/@angular/core/fesm2020/core.mjs:9146:33)

Reproduction

I’m unsure how to completely reproduce, and I’m unable to share the code due to NDA.

Expected Behavior

HighContrastModeDetector successfully constructs

Actual Behavior

Constructor fails on only 2 of my components at the line linked above due to the expected Observable<BreakpointObserver> being undefined.

Environment

Angular: Fails on 14.0.2, 14.1.3, and 14.2.0-rc.0
CDK/Material: CDK
Browser(s): Chrome Headless Karma/Jasmine
Operating System (e.g. Windows, macOS, Ubuntu): Amazon Linux 2

Issue Analytics

State:
Created a year ago
Reactions:1
Comments:9 (2 by maintainers)

Top GitHub Comments

1reaction

Chris2fourlawcommented, Sep 1, 2022

The same issue after upgrading angular version 13 -> 14.2.0.

This is relieving to hear. Do you know how to reproduce this?

0reactions

angular-automatic-lock-bot[bot]commented, Oct 18, 2022

This issue has been automatically locked due to inactivity. Please file a new issue if you are encountering a similar or related problem.

Read more about our automatic conversation locking policy.

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