fix: prevent possible errors when inputs property is not set

[web-padawan]

Description

Fixes vaadin/flow-components#6739

Updated checkValidity() method to check that this.inputs and this.value are defined before accessing them.

Type of change

• Bugfix

[rappenze]

Looks like this is the wrong place to fix the problem completely.

The same thing happens as well in other methods, e.g. here:

_shouldRemoveFocus(event) {
      const { relatedTarget } = event;
      return !this.inputs.some((el) => relatedTarget === (el.focusElement || el));
    }

[web-padawan]

Good point, thanks. I will check other methods too.

[web-padawan]

Updated the PR. I wasn't able to reproduce this exact error though as typically the web component can only receive and then lose focus when it is connected to the DOM and by this point of time inputs is set to empty array.

[sonarcloud]

Quality Gate passed

Issues
1 New issue
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud

[vaadin-bot]

Hi @web-padawan and @web-padawan, when i performed cherry-pick to this commit to 24.4, i have encountered the following issue. Can you take a look and pick it manually?
Error Message:
Error: Command failed: git cherry-pick 82bfd11
error: could not apply 82bfd11... fix: prevent possible errors when inputs property is not set (#8012)
hint: After resolving the conflicts, mark them with
hint: "git add/rm ", then run
hint: "git cherry-pick --continue".
hint: You can instead skip this commit with "git cherry-pick --skip".
hint: To abort and get back to the state before "git cherry-pick",
hint: run "git cherry-pick --abort".

[rappenze]

@web-padawan Just seen that you added target 24.4 but I never had this problems in 24.4. So maybe backport is not needed as there is all ok?

[lmorocz]

We do have problems with the original change using the latest v24.4.17 platform (v24.4.12 Vaadin Flow) version. In some cases the inputs property is still undefined in the ready phase:

generated-flow-imports-CjbTJID0.js:7519 Uncaught TypeError: Cannot read properties of undefined (reading 'filter')
    at CustomField.checkValidity (generated-flow-impor…CjbTJID0.js:7519:39)
    at CustomField.validate (indexhtml-GaOLT410.js:20753:28)
    at CustomField._requiredChanged (generated-flow-impor…CjbTJID0.js:7535:12)
    at Object.runMethodEffect [as fn] (indexhtml-GaOLT410.js:9666:39)
    at runEffects (indexhtml-GaOLT410.js:9210:16)
    at CustomField._propertiesChanged (indexhtml-GaOLT410.js:10301:7)
    at Dx.s2._propertiesChanged (FlowClient-CfFCB582.js:9090:12)
    at CustomField._flushProperties (indexhtml-GaOLT410.js:8203:16)
    at CustomField.ready (indexhtml-GaOLT410.js:10269:12)
    at CustomField.ready (indexhtml-GaOLT410.js:12080:13)
    at CustomField.ready (indexhtml-GaOLT410.js:15164:13)
    at CustomField.ready (indexhtml-GaOLT410.js:15443:13)
    at CustomField.ready (indexhtml-GaOLT410.js:20709:13)
    at CustomField.ready (indexhtml-GaOLT410.js:20882:11)
    at CustomField.ready (generated-flow-impor…CjbTJID0.js:7465:11)
    at Dx.s2.ready (FlowClient-CfFCB582.js:9095:12)

@web-padawan could you backport this fix to the 24.4 branch as well? 🙏🙇‍♂️