Issue #838 Implement extension point to run diagnosis tools when forked JVM times out

[olamy]

Signed-off-by: Olivier Lamy olamy@apache.org

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[Copilot]

Pull request overview

Adds a new Surefire/Failsafe extension point that lets plugins/extensions run diagnostic tooling when a forked test JVM hits forkedProcessTimeoutInSeconds, including a built-in (opt-in) jstack implementation plus ITs and site documentation.

Changes:

• Introduce ForkedProcessTimeoutExtension SPI + ForkedProcessTimeoutContext API and wire it into the fork timeout/kill path.
• Add plugin-side dispatcher/context implementation and a built-in JstackTimeoutExtension (disabled by default, configurable via a context map).
• Add unit tests, an integration test (SUREFIRE-838), and new site docs/menus for the feature.

Reviewed changes

Copilot reviewed 24 out of 24 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
surefire-its/src/test/resources/surefire-838-timeout-extension/src/test/java/surefire838/SleepingTest.java	Adds a hanging test used to trigger fork timeout in the IT project.
surefire-its/src/test/resources/surefire-838-timeout-extension/pom.xml	Consumer IT POM enabling timeout + configuring extension context keys and adding the extension dependency.
surefire-its/src/test/resources/surefire-838-timeout-extension-ext/src/main/resources/META-INF/services/org.apache.maven.surefire.extensions.ForkedProcessTimeoutExtension	Registers the IT extension implementation via ServiceLoader.
surefire-its/src/test/resources/surefire-838-timeout-extension-ext/src/main/java/org/apache/maven/surefire/its/extension/MarkerTimeoutExtension.java	Test extension that writes marker files when timeout/exited callbacks fire.
surefire-its/src/test/resources/surefire-838-timeout-extension-ext/pom.xml	Builds the IT extension JAR against the new extensions API.
surefire-its/src/test/java/org/apache/maven/surefire/its/jiras/Surefire838TimeoutExtensionIT.java	Integration test asserting the timeout extension callbacks (and best-effort jstack dump) occur.
surefire-extensions-api/src/main/java/org/apache/maven/surefire/extensions/util/CommandlineExecutor.java	Exposes the underlying Process so the fork PID can be queried.
surefire-extensions-api/src/main/java/org/apache/maven/surefire/extensions/ForkedProcessTimeoutExtension.java	New SPI interface invoked on fork timeout and fork exit.
surefire-extensions-api/src/main/java/org/apache/maven/surefire/extensions/ForkedProcessTimeoutContext.java	New context interface carrying fork diagnostics + extension configuration map.
surefire-booter/src/main/java/org/apache/maven/surefire/booter/SystemUtils.java	Adds pidOf(Process) (Java 9+ reflective Process.pid()) to support PID reporting.
pom.xml	Updates RAT excludes for the new ServiceLoader file in main resources.
maven-surefire-plugin/src/site/site.xml	Adds site menu entries for the timeout extension docs.
maven-surefire-plugin/src/site/markdown/timeout-extension-guide.md	New detailed guide for enabling built-in jstack and authoring extensions.
maven-surefire-plugin/src/site/markdown/examples/timeout-extension.md	New concise example/reference page for the timeout extension SPI.
maven-surefire-common/src/test/java/org/apache/maven/plugin/surefire/extensions/timeout/TimeoutExtensionDispatcherTest.java	Unit tests for dispatcher behavior (fan-out, exception isolation, context propagation, bounded execution).
maven-surefire-common/src/test/java/org/apache/maven/plugin/surefire/extensions/timeout/JstackTimeoutExtensionTest.java	Unit tests for built-in jstack extension enablement and output-location behavior.
maven-surefire-common/src/test/java/org/apache/maven/plugin/surefire/booterclient/output/ForkClientTest.java	Adds a test ensuring timeout listener fires once and before KILL is sent.
maven-surefire-common/src/main/resources/META-INF/services/org.apache.maven.surefire.extensions.ForkedProcessTimeoutExtension	Registers the built-in JstackTimeoutExtension via ServiceLoader.
maven-surefire-common/src/main/java/org/apache/maven/plugin/surefire/extensions/timeout/TimeoutExtensionDispatcher.java	New plugin-side ServiceLoader discovery + bounded callback execution.
maven-surefire-common/src/main/java/org/apache/maven/plugin/surefire/extensions/timeout/JstackTimeoutExtension.java	Built-in (opt-in) implementation that captures a jstack dump on timeout.
maven-surefire-common/src/main/java/org/apache/maven/plugin/surefire/extensions/timeout/DefaultForkedProcessTimeoutContext.java	Default immutable context implementation for extensions.
maven-surefire-common/src/main/java/org/apache/maven/plugin/surefire/booterclient/output/ForkClient.java	Adds a one-shot “timeout detected” listener invoked immediately before sending KILL.
maven-surefire-common/src/main/java/org/apache/maven/plugin/surefire/booterclient/ForkStarter.java	Wires extension dispatch into fork lifecycle (on-timeout-before-kill + after-exit) and passes context/config.
maven-surefire-common/src/main/java/org/apache/maven/plugin/surefire/AbstractSurefireMojo.java	Adds forkedProcessTimeoutExtensionContext parameter and passes it into ForkStarter.