Allow partly parallel Maven execution

This partly fixes Maven execution in parallel forks, because it postpones
evaluating of the rootFolder (`user.dir` value) until it is really needed
during execution. Without the fix the path could be evaluated in the main
process, meaning the `user.dir` is not set correctly to the tested module.

It still does not allow reusing of the forks (reuseForks parameter in
maven-surefire-plugin and maven-failsafe-plugin), but at least allows
parallel execution (forkCount greater than 1).

When reusing the forks, the SnapshotSystemJUnit5.finishedAllTests()
complains that it was called more than once, so the reuseForks has to
be disabled (set to false).

This partly fixes #551.

Signed-off-by: Oldřich Jedlička <[email protected]>

Author: oldium

jvm/CHANGELOG.md

@@ -13,6 +13,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ## [Unreleased]
 ### Fixed
 - Unsupported test sources (such as `FieldSource`) no longer cause the JUnit5 runner to crash. ([#550](https://github.com/diffplug/selfie/pull/550) fixes [#549](https://github.com/diffplug/selfie/issues/549))
+- Partly allow parallel Maven execution with surefire and failsafe plugins with `forkCount` greater than one by making evaluation of few properties lazy. This postpones evaluation into the forks. Still, due to internal Selfie state tracking, this needs to be run with `reuseForks` set to `false`. ([#557](https://github.com/diffplug/selfie/pull/557) partly fixes [#551](https://github.com/diffplug/selfie/issues/551))
 ### Changed
 - Bump minimum required Kotest from `5.4.0` to `5.6.0` ([#535](https://github.com/diffplug/selfie/pull/535))
   - required to fix `java.lang.NoSuchMethodError: 'long kotlin.time.Duration$Companion.milliseconds-UwyO8pc(long)'`

jvm/selfie-runner-junit5/src/main/kotlin/com/diffplug/selfie/junit5/SnapshotFileLayoutJUnit5.kt

@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2023-2024 DiffPlug
+ * Copyright (C) 2023-2025 DiffPlug
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -27,13 +27,16 @@ class SnapshotFileLayoutJUnit5(settings: SelfieSettingsAPI, override val fs: FS)
   internal val smuggledError =
       AtomicReference<Throwable?>(
           if (settings is SelfieSettingsSmuggleError) settings.error else null)
-  override val rootFolder = TypedPath.ofFolder(settings.rootFolder.absolutePath)
-  private val otherSourceRoots = settings.otherSourceRoots
+  internal val settings = settings
+  override val rootFolder: TypedPath by lazy {
+    TypedPath.ofFolder(settings.rootFolder.absolutePath)
+  }
+  private val otherSourceRoots: List<java.io.File> by lazy { settings.otherSourceRoots }
   override val allowMultipleEquivalentWritesToOneLocation =
       settings.allowMultipleEquivalentWritesToOneLocation
   override val javaDontUseTripleQuoteLiterals = settings.javaDontUseTripleQuoteLiterals
   val snapshotFolderName = settings.snapshotFolderName
-  internal val unixNewlines = inferDefaultLineEndingIsUnix(rootFolder, fs)
+  internal val unixNewlines: Boolean by lazy { inferDefaultLineEndingIsUnix(rootFolder, fs) }
   val extension: String = ".ss"
   private val cache =
       SourcePathCache(this::computePathForCall, Runtime.getRuntime().availableProcessors() * 4)

jvm/selfie-runner-kotest/src/commonMain/kotlin/com/diffplug/selfie/kotest/SnapshotFileLayoutKotest.kt

@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2024 DiffPlug
+ * Copyright (C) 2024-2025 DiffPlug
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.