feat: allow skipping Vaadin maven plugin execution during a build

[jorgheymans]

Description

It can be sometimes desirable to skip the execution of the Vaadin maven plugin, for example when running the project unit tests from the command line, to speed up the project build.

Fixes #21426

Type of change

• Bugfix
• [ x] Feature

Checklist

• [x ] I have read the contribution guide: https://vaadin.com/docs/latest/guide/contributing/overview/
• [ x] I have added a description following the guideline.
• [ x] The issue is created in the corresponding repository and I have referenced it.
• [x ] I have added tests to ensure my change is effective and works as intended.
• [ x] New and existing tests are passing locally with my change.
• [ x] I have performed self-review and corrected misspellings.

Additional for Feature type of change

• [x ] Enhancement / new feature was discussed in a corresponding GitHub issue and Acceptance Criteria were created.

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[mcollovati]

A couple of preliminary comments.
About the vaadin-skip-test integration test for the maven plugin, it would be good to add a verify.bsh file that checks the build output to ensure the plugin execution has been skipped. You can take a look at the offending-dependency-project test for inspiration.

[jorgheymans]

Not sure what to make of all these build errors, but locally the build passes with tests and integration tests now.

[mcollovati]

Not sure what to make of all these build errors, but locally the build passes with tests and integration tests now.

No further actions for you at the moment. Builds must be restarted after code review by a Vaadin team member.

BTW, thanks for the contribution!

[github-actions]

Test Results

1 272 files  +1  1 272 suites  +1   1h 19m 23s ⏱️ + 3m 35s
8 798 tests +2  8 731 ✅ +2  67 💤 ±0  0 ❌ ±0 
9 249 runs  +8  9 172 ✅ +8  77 💤 ±0  0 ❌ ±0 

Results for commit 6f0165e. ± Comparison against base commit b091938.

♻️ This comment has been updated with latest results.

[jorgheymans]

Trying to run spotless to fix formatting errors gives this:

mvn spotless:apply
[INFO] Processing build on daemon b33b37ad
[INFO] Scanning for projects...
[INFO] BuildTimeEventSpy is registered.
[INFO] 
[INFO] Using the SmartBuilder implementation with a thread count of 7
[INFO] 
[INFO] --------------------< com.vaadin:flow-maven-plugin >--------------------
[INFO] Building Flow Maven plugin 25.0-SNAPSHOT
[INFO]   from pom.xml
[INFO] ----------------------------[ maven-plugin ]----------------------------
[INFO] 
[INFO] --- spotless:3.0.0:apply (default-cli) @ flow-maven-plugin ---
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time:  0.278 s (Wall Clock)
[INFO] Finished at: 2025-10-16T15:08:27+02:00
[INFO] ------------------------------------------------------------------------
[ERROR] StackOverflowError -> [Help 1]
**[ERROR] java.lang.StackOverflowError**
[ERROR] 

[mcollovati]

Works for me. Weird error.
I pushed the formatting changes

[mcollovati]

@jorgheymans are you using mvnd? Maybe an issue with it, even though I tried and could not reproduce.
Maybe a mvnd --stop and retry?
Or run with -X to get the error trace.

[jorgheymans]

Indeed, mvnd was the culprit. Now it runs but with below error which I guess is not related to my changes. Thank you for pushing the format change.

[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time:  3.788 s (Wall Clock)
[INFO] Finished at: 2025-10-16T15:16:05+02:00
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal com.diffplug.spotless:spotless-maven-plugin:3.0.0:apply (default-cli) on project flow-maven-plugin: There were 1 lint error(s), they must be fixed or suppressed.
[ERROR]   src/it/frontend-scanner-tuning-project/src/main/frontend/project-component.js:LINE_UNDEFINED prettier-format(java.lang.IllegalStateException) Can't automatically determine node executable and none was specifically supplied! (...)
[ERROR]   Resolve these lints or suppress with `<lintSuppressions>`
[ERROR] -> [Help 1]
[ERROR] 
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR]

[sonarqubecloud]

Quality Gate passed

Issues
2352 New issues
2 Accepted issues

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

See analysis details on SonarQube Cloud