// This adds support for compiling and testing against a different Java runtime.
// This is the only way to build against JVMs not yet supported by Gradle itself.

import org.gradle.internal.jvm.Jvm

def jvmForTests = {
  def runtimeJavaHome = propertyOrDefault("runtime.java.home", System.getenv('RUNTIME_JAVA_HOME'))
  if (!runtimeJavaHome) {
    return Jvm.current()
  } else {
    return Jvm.forHome(file(runtimeJavaHome))
  }
}()
def jvmGradle = Jvm.current()

def differentTestJvm = (jvmGradle.javaHome.canonicalPath != jvmForTests.javaHome.canonicalPath)

// Set up tasks to use the alternative Java.
if (differentTestJvm) {
  configure(rootProject) {
    task testJvmWarning() {
      doFirst {
        logger.warn("This Java will be used for running tests: ${jvmForTests.javaExecutable}")
      }
    }
  }

  // Set up test tasks to use the alternative JVM.
  allprojects {
    tasks.withType(Test) {
      dependsOn ":testJvmWarning"
      executable = jvmForTests.javaExecutable
    }
  }
}