Use Groovy convenience method to handle process output

Author: marcphilipp

platform-tooling-support-tests/platform-tooling-support-tests.gradle.kts

@@ -22,6 +22,9 @@ dependencies {
 	testImplementation("com.tngtech.archunit:archunit-junit5-api:${Versions.archunit}") {
 		because("checking the architecture of JUnit 5")
 	}
+	testImplementation("org.codehaus.groovy:groovy-all:${Versions.groovy}") {
+		because("it provides convenience methods to handle process output")
+	}
 	testRuntimeOnly("com.tngtech.archunit:archunit-junit5-engine:${Versions.archunit}") {
 		because("contains the ArchUnit TestEngine implementation")
 	}

platform-tooling-support-tests/src/test/java/platform/tooling/support/tests/ModularUserGuideTests.java

@@ -25,6 +25,7 @@
 import java.util.List;
 import java.util.spi.ToolProvider;
 
+import org.codehaus.groovy.runtime.ProcessGroovyMethods;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.io.TempDir;
 import platform.tooling.support.Helper;
@@ -138,9 +139,10 @@ private static List<String> junit(Path temp, Writer out, Writer err) throws Exce
 		// System.out.println("______________");
 		// command.forEach(System.out::println);
 
-		var builder = new ProcessBuilder(command).directory(temp.toFile()).inheritIO();
+		var builder = new ProcessBuilder(command).directory(temp.toFile());
 		var java = builder.start();
-		var code = java.waitFor();
+		ProcessGroovyMethods.waitForProcessOutput(java, out, err);
+		var code = java.exitValue();
 
 		if (code != 0) {
 			System.out.println(out);