Persist authored Age generation plans (#31)

build.gradle

@@ -148,42 +148,79 @@ neoForge {
     }
 }
 
-// GameTests generate Ages, so their dedicated world can grow quickly across runs.
-// Never auto-delete a caller-supplied gameTestRunDir or a normal dev world.
-long gameTestWorldLimitMiB = providers.gradleProperty('gameTestMaxWorldMiB').orElse('512').get().toLong()
-if (gameTestWorldLimitMiB <= 0) {
-    throw new GradleException('gameTestMaxWorldMiB must be a positive number')
-}
+// Every default run gets a fresh world. Failed worlds stay available until a
+// successful run; caller-supplied directories are never managed here.
 boolean customGameTestRunDir = providers.gradleProperty('gameTestRunDir').isPresent()
-File dedicatedGameTestDir = layout.buildDirectory.dir('gametest-run').get().asFile.canonicalFile
+File dedicatedGameTestBuildDir = layout.buildDirectory.get().asFile
+File dedicatedGameTestDir = layout.buildDirectory.dir('gametest-run').get().asFile
 File dedicatedGameTestWorld = new File(dedicatedGameTestDir, 'world')
-def cleanOversizedGameTestWorld = tasks.register('cleanOversizedGameTestWorld') {
+File gameTestSuccessMarker = new File(dedicatedGameTestDir, '.last-gametest-succeeded')
+def prepareGameTestWorld = tasks.register('prepareGameTestWorld') {
+    onlyIf { !customGameTestRunDir }
     doLast {
-        if (customGameTestRunDir) {
-            getLogger().lifecycle('Skipping automatic GameTest world cleanup for custom gameTestRunDir')
-            return
-        }
-
-        def worldDir = dedicatedGameTestWorld
-        if (!worldDir.isDirectory() || java.nio.file.Files.isSymbolicLink(worldDir.toPath())) {
-            return
-        }
-
-        def paths = java.nio.file.Files.walk(worldDir.toPath()).withCloseable { it.toList() }
-        long bytes = paths.sum(0L) { path ->
-            java.nio.file.Files.isRegularFile(path, java.nio.file.LinkOption.NOFOLLOW_LINKS)
-                    ? java.nio.file.Files.size(path) : 0L
-        }
-        long limit = gameTestWorldLimitMiB * 1024L * 1024L
-        if (bytes > limit) {
-            getLogger().lifecycle('Removing oversized GameTest world {} ({} MiB; limit {} MiB)',
-                    worldDir, Math.ceil(bytes / 1048576d) as long, gameTestWorldLimitMiB)
-            paths.toSorted(java.util.Comparator.reverseOrder()).each { java.nio.file.Files.delete(it) }
+        java.nio.file.Files.deleteIfExists(gameTestSuccessMarker.toPath())
+        File preserved = GameTestWorlds.preserve(dedicatedGameTestBuildDir, dedicatedGameTestDir)
+        if (preserved != null) logger.lifecycle('Preserved GameTest world for inspection at {}', preserved)
+    }
+}
+def finishGameTestWorld = tasks.register('finishGameTestWorld') {
+    onlyIf { !customGameTestRunDir }
+    doLast {
+        if (gameTestSuccessMarker.exists()) {
+            GameTestWorlds.clean(dedicatedGameTestBuildDir, dedicatedGameTestDir)
+            java.nio.file.Files.delete(gameTestSuccessMarker.toPath())
+        } else {
+            File preserved = GameTestWorlds.preserve(dedicatedGameTestBuildDir, dedicatedGameTestDir)
+            if (preserved != null) logger.lifecycle('Preserved GameTest world for inspection at {}', preserved)
         }
     }
 }
 tasks.named('runGameTestServer').configure {
-    dependsOn(cleanOversizedGameTestWorld)
+    dependsOn(prepareGameTestWorld)
+    finalizedBy(finishGameTestWorld)
+    doLast {
+        if (!customGameTestRunDir) {
+            GameTestWorlds.check(dedicatedGameTestBuildDir, dedicatedGameTestDir)
+            java.nio.file.Files.createFile(gameTestSuccessMarker.toPath())
+        }
+    }
+}
+
+class GameTestWorlds {
+    static void check(File buildDir, File runDir) {
+        [buildDir, runDir, new File(runDir, 'world'), new File(runDir, 'failed-worlds')].each { path ->
+            if (java.nio.file.Files.isSymbolicLink(path.toPath())) {
+                throw new GradleException("Refusing to manage a symlinked GameTest path: ${path}")
+            }
+        }
+    }
+
+    static File preserve(File buildDir, File runDir) {
+        File world = new File(runDir, 'world')
+        if (!world.exists()) return null
+        check(buildDir, runDir)
+        if (!world.isDirectory()) throw new GradleException("Expected a GameTest world directory: ${world}")
+        File failures = new File(runDir, 'failed-worlds')
+        java.nio.file.Files.createDirectories(failures.toPath())
+        String snapshot = java.time.format.DateTimeFormatter.ofPattern('yyyyMMdd-HHmmss-SSS')
+                .format(java.time.LocalDateTime.now()) + '-' + java.util.UUID.randomUUID()
+        File destination = new File(failures, snapshot)
+        java.nio.file.Files.move(world.toPath(), destination.toPath())
+        return destination
+    }
+
+    static void clean(File buildDir, File runDir) {
+        check(buildDir, runDir)
+        [new File(runDir, 'world'), new File(runDir, 'failed-worlds')].each { root ->
+            if (root.exists()) {
+                java.nio.file.Files.walk(root.toPath()).withCloseable { paths ->
+                    paths.sorted(java.util.Comparator.reverseOrder()).forEach { path ->
+                        java.nio.file.Files.delete(path)
+                    }
+                }
+            }
+        }
+    }
 }
 
 // Sets up a dependency configuration called 'localRuntime'.