Fix gradle func tests running in idea (#74811)

* Fix gradle func tests running in idea

* Tweak wrapper task

build-conventions/build.gradle

@@ -60,7 +60,7 @@ dependencies {
     compileOnly "com.puppycrawl.tools:checkstyle:8.42"
 }
 
-project.getPlugins().withType(JavaBasePlugin.class, javaBasePlugin -> {
+project.getPlugins().withType(JavaBasePlugin.class) {
     java.getModularity().getInferModulePath().set(false);
     eclipse.getClasspath().getFile().whenMerged { classpath ->
         /*
@@ -69,9 +69,8 @@ project.getPlugins().withType(JavaBasePlugin.class, javaBasePlugin -> {
          * in the usual build folder because eclipse becomes *very* sad
          * if we delete it. Which `gradlew clean` does all the time.
          */
-        int i = 0;
-        classpath.getEntries().stream().filter(e -> e instanceof SourceFolder).forEachOrdered(s ->
-                s.setOutput("out/eclipse"+i++)
-        )
+        classpath.getEntries().findAll{ s -> s instanceof SourceFolder }.eachWithIndex { s, i ->
+            s.setOutput("out/eclipse" + i)
+        }
     }
-})
+}

build-conventions/src/main/java/org/elasticsearch/gradle/internal/conventions/EclipseConventionPlugin.java

@@ -131,8 +131,8 @@ public void execute(Delete delete) {
     }
 
     private File root(Project project) {
-        return project.getGradle().getParent() == null ?
-        project.getRootDir() :
-        root(project.getGradle().getParent().getRootProject());
+        return project.getRootProject().getName().equals("elasticsearch") ?
+                project.getRootProject().getRootDir() :
+                project.getRootDir().getParentFile();
     }
 }

build-tools-internal/gradle/wrapper/gradle-wrapper.properties

@@ -0,0 +1,6 @@
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-7.1-all.zip
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists
+distributionSha256Sum=a9e356a21595348b6f04b024ed0b08ac8aea6b2ac37e6c0ef58e51549cd7b9cb

build.gradle

@@ -24,6 +24,8 @@ import static org.elasticsearch.gradle.util.GradleUtils.maybeConfigure
 import org.gradle.plugins.ide.eclipse.model.ProjectDependency
 import org.elasticsearch.gradle.internal.InternalPluginBuildPlugin
 import org.elasticsearch.gradle.internal.ResolveAllDependencies
+import java.nio.file.Files
+import static java.nio.file.StandardCopyOption.REPLACE_EXISTING;
 
 plugins {
   id 'lifecycle-base'
@@ -380,6 +382,9 @@ tasks.named("wrapper").configure {
     final String sha256Sum = new String(sha256Uri.toURL().bytes)
     wrapper.getPropertiesFile() << "distributionSha256Sum=${sha256Sum}\n"
     println "Added checksum to wrapper properties"
+    // copy wrapper properties file to build-tools-internal to allow seamless idea integration
+    def file = new File("build-tools-internal/gradle/wrapper/gradle-wrapper.properties")
+    Files.copy(wrapper.getPropertiesFile().toPath(), file.toPath(), REPLACE_EXISTING)
     // Update build-tools to reflect the Gradle upgrade
     // TODO: we can remove this once we have tests to make sure older versions work.
     project.file('build-tools-internal/src/main/resources/minimumGradleVersion').text = gradleVersion