Avoid creating sessions during invalidate

[jamesfredley]

Summary

• Avoid creating a servlet session when GrailsHttpSession.invalidate() is called without an existing session
• Preserve invalidated-wrapper semantics when an existing request session is invalidated before wrapper access
• Add GrailsHttpSessionSpec regression coverage

Verification

• .\\gradlew.bat --no-daemon --no-parallel --max-workers=1 :grails-web-common:test --tests "grails.web.servlet.mvc.GrailsHttpSessionSpec"
• Review gate: Oracle GREEN and Codex GREEN for diff hash 81bc27b564a1b4dc3e0d900a1d56aaae6519941b

Notes

• Full aggregate gate was attempted sequentially but aborted after unrelated Gradle worker connection resets and a stale/corrupt XML report from an unrelated Hibernate module. The focused affected-module spec passed after clearing that stale artifact.

[Copilot]

Pull request overview

This PR adjusts GrailsHttpSession.invalidate() so it no longer forces creation of a servlet HttpSession when none exists, while still ensuring that an already-existing request session can be invalidated even if the wrapper was never accessed. This aligns invalidation behavior with “don’t create on invalidate” expectations and adds a regression spec in grails-web-common to prevent regressions.

Changes:

• Update GrailsHttpSession.invalidate() to use request.getSession(false) (no-create) and only invalidate when a session actually exists.
• Ensure wrapper invalidation semantics remain consistent when an existing request session is invalidated before any wrapper access.
• Add GrailsHttpSessionSpec coverage for both “no existing session” and “existing session” invalidation paths.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
grails-web-common/src/main/groovy/grails/web/servlet/mvc/GrailsHttpSession.java	Stops invalidate() from creating a servlet session; invalidates only if an existing session is present (wrapper or request).
grails-web-common/src/test/groovy/grails/web/servlet/mvc/GrailsHttpSessionSpec.groovy	Adds regression tests validating non-creation on invalidate and correct invalidation behavior when a request session already exists.

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[testlens-app]

🚨 TestLens detected 1 failed test 🚨

Here is what you can do:

1. Inspect the test failures carefully.
2. If you are convinced that some of the tests are flaky, you can mute them below.
3. Finally, trigger a rerun by checking the rerun checkbox.

Test Summary

CI / Functional Tests (Java 21, indy=true) > :grails-test-examples-app1:integrationTest

Test	Runs
ForwardingSpec > Test forwarding to an action which returns a Map	❌

🏷️ Commit: a812020
▶️ Tests: 42524 executed
⚪️ Checks: 45/45 completed

Test Failures

ForwardingSpec > Test forwarding to an action which returns a Map (:grails-test-examples-app1:integrationTest in CI / Functional Tests (Java 21, indy=true))

Condition not satisfied:

$('li', text: 'Jeff')
|
[]

	at functionaltests.ForwardingSpec.$tt__$spock_feature_1_5(ForwardingSpec.groovy:74)
	at functionaltests.ForwardingSpec.Test forwarding to an action which returns a Map_closure6(ForwardingSpec.groovy)
	at grails.gorm.transactions.GrailsTransactionTemplate$1.doInTransaction(GrailsTransactionTemplate.groovy:72)
	at org.springframework.transaction.support.TransactionTemplate.execute(TransactionTemplate.java:137)
	at grails.gorm.transactions.GrailsTransactionTemplate.executeAndRollback(GrailsTransactionTemplate.groovy:69)
	at functionaltests.ForwardingSpec.Test forwarding to an action which returns a Map(ForwardingSpec.groovy)

Muted Tests

Select tests to mute in this pull request:

• ForwardingSpec > Test forwarding to an action which returns a Map

Reuse successful test results:

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[codecov]

Codecov Report

❌ Patch coverage is 80.00000% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 49.4912%. Comparing base (66cd24c) to head (a812020).

Files with missing lines	Patch %	Lines
...oovy/grails/web/servlet/mvc/GrailsHttpSession.java	80.0000%	0 Missing and 1 partial ⚠️

Additional details and impacted files

@@                Coverage Diff                 @@
##                8.0.x     #15813        +/-   ##
==================================================
+ Coverage     49.4842%   49.4912%   +0.0070%     
- Complexity      16697      16701         +4     
==================================================
  Files            1947       1947                
  Lines           92474      92477         +3     
  Branches        16152      16154         +2     
==================================================
+ Hits            45760      45768         +8     
+ Misses          39606      39602         -4     
+ Partials         7108       7107         -1     

Files with missing lines	Coverage Δ
...oovy/grails/web/servlet/mvc/GrailsHttpSession.java	31.2500% <80.0000%> (+9.9385%)	⬆️

... and 2 files with indirect coverage changes

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