test: Add sack util test

buildSrc/src/RepoDownload.kt

@@ -0,0 +1,41 @@
+import java.net.URI
+import java.util.zip.ZipInputStream
+import org.gradle.api.DefaultTask
+import org.gradle.api.file.DirectoryProperty
+import org.gradle.api.provider.Property
+import org.gradle.api.tasks.Input
+import org.gradle.api.tasks.OutputDirectory
+import org.gradle.api.tasks.TaskAction
+
+abstract class RepoDownload : DefaultTask() {
+	@get:Input
+	abstract val hash: Property<String>
+
+	@get:OutputDirectory
+	abstract val outputDirectory: DirectoryProperty
+
+	init {
+		outputDirectory.convention(project.layout.buildDirectory.dir("extracted-test-repo"))
+	}
+
+	@TaskAction
+	fun performDownload() {
+		val outputDir = outputDirectory.asFile.get().absoluteFile
+		outputDir.mkdirs()
+		URI("https://github.com/notEnoughUpdates/notEnoughUpdates-rEPO/archive/${hash.get()}.zip").toURL().openStream()
+			.let(::ZipInputStream)
+			.use { zipInput ->
+				while (true) {
+					val entry = zipInput.nextEntry ?: break
+					val destination = outputDir.resolve(
+						entry.name.substringAfter('/')).absoluteFile
+					require(outputDir in generateSequence(destination) { it.parentFile })
+					if (entry.isDirectory) continue
+					destination.parentFile.mkdirs()
+					destination.outputStream().use { output ->
+						zipInput.copyTo(output)
+					}
+				}
+			}
+	}
+}