An attempt to use gradle's eclipse plugin to provide us with src paths for libs (#14870)

Author: dweiss

build-tools/build-infra/src/main/groovy/lucene.ide.eclipse.gradle

@@ -42,14 +42,28 @@ if (gradle.startParameter.taskNames.contains("eclipse")) {
     classpath {
       defaultOutputDir = file('build/eclipse')
 
+      downloadSources = true
+      downloadJavadoc = false
+
+      plusConfigurations += allprojects.findAll{ prj ->
+        return prj.plugins.hasPlugin(JavaPlugin)
+      }.collectMany {
+        return [ it.configurations.compileClasspath, it.configurations.testCompileClasspath ]
+      }
+
       file {
-        beforeMerged { classpath ->
+        whenMerged { classpath ->
           classpath.entries.removeAll {
-            it.kind == "src"
+            return it.kind == "src" || (it.kind == "lib" && it.getPath() ==~ /(.+)lucene-.*\.jar/)
+          }
+
+          // I'm not sure what these attributes are supposed to do. Keeping the previous version of having no-attributes.
+          classpath.entries.each {
+            if (it.kind == "lib") {
+              it.getEntryAttributes().clear()
+            }
           }
-        }
 
-        whenMerged { classpath ->
           def projects = allprojects.findAll { prj ->
             return prj.plugins.hasPlugin(JavaPlugin)
           }
@@ -62,31 +76,20 @@ if (gradle.startParameter.taskNames.contains("eclipse")) {
             'tools'
           ] as Set
           Set<String> sources = []
-          Set<File> jars = []
           projects.each { prj ->
             prj.sourceSets.each { sourceSet ->
               if (sourceSetNames.contains(sourceSet.name)) {
                 sources += sourceSet.java.srcDirs.findAll { dir -> dir.exists() }.collect { dir -> relativize(dir) }
                 sources += sourceSet.resources.srcDirs.findAll { dir -> dir.exists() }.collect { dir -> relativize(dir) }
               }
             }
-
-            // This is hacky - we take the resolved compile classpath and just
-            // include JAR files from there. We should probably make it smarter
-            // by looking at real dependencies. But then: this Eclipse configuration
-            // doesn't really separate sources anyway so why bother.
-            jars += prj.configurations.compileClasspath.resolve()
-            jars += prj.configurations.testCompileClasspath.resolve()
           }
 
           classpath.entries += sources.sort().collect { name ->
             def sourceFolder = new SourceFolder(name, "build/eclipse/" + name)
             sourceFolder.setExcludes(["module-info.java"])
             return sourceFolder
           }
-          classpath.entries += jars.unique().findAll { location -> location.isFile() && !(location.name ==~ /lucene-.*\.jar/) }.collect { location ->
-            new LibEntry(location.toString())
-          }
         }
       }
     }
@@ -132,23 +135,3 @@ if (gradle.startParameter.taskNames.contains("eclipse")) {
   }
 }
 
-public class LibEntry implements ClasspathEntry {
-  private String path;
-
-  LibEntry(String path) {
-    this.path = path;
-  }
-
-  @Override
-  String getKind() {
-    return "lib"
-  }
-
-  @Override
-  void appendNode(Node node) {
-    node.appendNode("classpathentry", Map.of(
-        "kind", "lib",
-        "path", path
-        ))
-  }
-}

gradle/ide/eclipse/dot.settings/org.eclipse.jdt.core.prefs

@@ -3,6 +3,8 @@ eclipse.preferences.version=1
 org.eclipse.jdt.core.compiler.codegen.targetPlatform=@eclipseJavaVersion@
 org.eclipse.jdt.core.compiler.compliance=@eclipseJavaVersion@
 org.eclipse.jdt.core.compiler.source=@eclipseJavaVersion@
+# this turns off split package checks, which gradle-api jar contains. https://github.com/gradle/gradle/issues/19577
+org.eclipse.jdt.core.compiler.ignoreUnnamedModuleForSplitPackage=enabled
 # Note: all compiler flags are defined in ECJ linter configuration
 @ecj-lint-config@
 org.eclipse.jdt.core.formatter.align_type_members_on_columns=false