Test example scripts against latest code (#456)

Add a new test case that verifies running the example Kotlin script
against the current library code, i.e. a SNAPSHOT artifact compiled just
before the tests and published to Maven local.

Prevents regresions like #426 (Kotlin notebooks issue) for Kotlin
scripts. Follow-up to #432 for example-scripts.

Author: gabrielfeo

examples/build.gradle.kts

@@ -17,13 +17,6 @@ project("example-project") {
 
 val exampleTestTasks = ArrayList<TaskProvider<*>>()
 
-exampleTestTasks += tasks.register<Exec>("runExampleScript") {
-    group = "Application"
-    description = "Runs the './example-scripts/example-script.main.kts' script"
-    commandLine("kotlinc", "-script", file("./example-scripts/example-script.main.kts"))
-    environment("JAVA_OPTS", "-Xmx1g")
-}
-
 exampleTestTasks += tasks.register("runExampleProject") {
     group = "Application"
     description = "Runs examples/example-project"

library/build.gradle.kts

@@ -113,4 +113,5 @@ tasks.named<Test>("examplesTest") {
     inputs.files(files(publishUnsignedSnapshotDevelocityApiKotlinPublicationToMavenLocal))
         .withPropertyName("snapshotPublicationArtifacts")
         .withNormalizer(ClasspathNormalizer::class)
+    maxParallelForks = 4
 }

library/src/examplesTest/kotlin/com/gabrielfeo/develocity/api/example/script/ScriptsTest.kt

@@ -0,0 +1,50 @@
+package com.gabrielfeo.develocity.api.example.script
+
+import com.gabrielfeo.develocity.api.example.copyFromResources
+import com.gabrielfeo.develocity.api.example.runInShell
+import org.junit.jupiter.api.Assertions.assertTrue
+import org.junit.jupiter.api.BeforeEach
+import org.junit.jupiter.api.Test
+import org.junit.jupiter.api.io.TempDir
+import java.nio.file.Path
+import kotlin.io.path.div
+
+class ScriptsTest {
+
+    @TempDir
+    lateinit var tempDir: Path
+
+    @BeforeEach
+    fun setup() {
+        copyFromResources("/examples", tempDir)
+    }
+
+    @Test
+    fun testMostFrequentBuildsScript() {
+        val script = tempDir / "examples/example-scripts/example-script.main.kts"
+        val replacedScript = forceUseOfMavenLocalSnapshotArtifact(script)
+        val output = runInShell(tempDir, "kotlin '$replacedScript'").trim()
+        val tableRegex = Regex("""(?ms)^[-]+\nMost frequent builds:\n\s*\n(.+\|\s*\d+\s*\n?)+""")
+        assertTrue(tableRegex.containsMatchIn(output)) {
+            "Expected match for pattern '$tableRegex' in output '$output'"
+        }
+    }
+
+    /**
+     * Replaces the dependency declaration in the script with a SNAPSHOT version and adds the maven local repository.
+     */
+    private fun forceUseOfMavenLocalSnapshotArtifact(scriptPath: Path): Path {
+        val mavenLocal = checkNotNull(System.getProperty("user.home")).let { "$it/.m2/repository" }
+        val scriptText = scriptPath.toFile().readText()
+            val replaced = scriptText.replace(
+                Regex("@file:DependsOn\\([^)]+\\)"),
+                """
+                    @file:DependsOn("com.gabrielfeo:develocity-api-kotlin:SNAPSHOT")
+                    @file:Repository("file://$mavenLocal")
+                """.trimIndent(),
+        )
+        val replacedPath = tempDir.resolve("examples/example-scripts/example-script-SNAPSHOT.main.kts")
+        replacedPath.toFile().writeText(replaced)
+        return replacedPath
+    }
+}