[superbuilder] toBuilder + singular + javac6 was broken

superbuilder generated the node `x.pluralName(plural == null ? Collections.emptyList() : plural)`.
java6 is not smart enough to infer the appropriate generics for the emptyList() call.
Fixed by always specifying the needed type explicitly: Collections.<String>emptyList();

5 files changed, 27 insertions, 11 deletions

diff --git a/src/core/lombok/eclipse/handlers/EclipseSingularsRecipes.java b/src/core/lombok/eclipse/handlers/EclipseSingularsRecipes.java
index 760f5282..d099cab2 100755
--- a/src/core/lombok/eclipse/handlers/EclipseSingularsRecipes.java
+++ b/src/core/lombok/eclipse/handlers/EclipseSingularsRecipes.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2015-2020 The Project Lombok Authors.
+ * Copyright (C) 2015-2021 The Project Lombok Authors.
  * 
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -451,7 +451,17 @@ public class EclipseSingularsRecipes {
 			statements.add(0, nullCheck);
 		}
 		
+		protected abstract int getTypeArgumentsCount();
+		
 		protected abstract char[][] getEmptyMakerReceiver(String targetFqn);
 		protected abstract char[] getEmptyMakerSelector(String targetFqn);
+		
+		public MessageSend getEmptyExpression(String targetFqn, SingularData data, EclipseNode typeNode, ASTNode source) {
+			MessageSend send = new MessageSend();
+			send.receiver = generateQualifiedNameRef(source, getEmptyMakerReceiver(targetFqn));
+			send.selector = getEmptyMakerSelector(targetFqn);
+			send.typeArguments = createTypeArgs(getTypeArgumentsCount(), false, typeNode, data.getTypeArgs());
+			return send;
+		}
 	}
 }
diff --git a/src/core/lombok/eclipse/handlers/HandleSuperBuilder.java b/src/core/lombok/eclipse/handlers/HandleSuperBuilder.java
index d9c8946f..fc4eb117 100644
--- a/src/core/lombok/eclipse/handlers/HandleSuperBuilder.java
+++ b/src/core/lombok/eclipse/handlers/HandleSuperBuilder.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2013-2020 The Project Lombok Authors.
+ * Copyright (C) 2013-2021 The Project Lombok Authors.
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -817,9 +817,7 @@ public class HandleSuperBuilder extends EclipseAnnotationHandler<SuperBuilder> {
 			ms.arguments = tgt;
 		} else {
 			Expression ifNull = new EqualExpression(tgt[0], new NullLiteral(0, 0), OperatorIds.EQUAL_EQUAL);
-			MessageSend emptyCollection = new MessageSend();
-			emptyCollection.receiver = generateQualifiedNameRef(source, bfd.singularData.getSingularizer().getEmptyMakerReceiver(bfd.singularData.getTargetFqn()));
-			emptyCollection.selector = bfd.singularData.getSingularizer().getEmptyMakerSelector(bfd.singularData.getTargetFqn());
+			MessageSend emptyCollection = bfd.singularData.getSingularizer().getEmptyExpression(bfd.singularData.getTargetFqn(), bfd.singularData, type, source);
 			ms.arguments = new Expression[] {new ConditionalExpression(ifNull, emptyCollection, tgt[1])};
 		}
 		ms.receiver = new SingleNameReference(BUILDER_VARIABLE_NAME, 0);
diff --git a/src/core/lombok/eclipse/handlers/singulars/EclipseGuavaSingularizer.java b/src/core/lombok/eclipse/handlers/singulars/EclipseGuavaSingularizer.java
index 395d2e59..7dcf18c9 100755
--- a/src/core/lombok/eclipse/handlers/singulars/EclipseGuavaSingularizer.java
+++ b/src/core/lombok/eclipse/handlers/singulars/EclipseGuavaSingularizer.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2015-2020 The Project Lombok Authors.
+ * Copyright (C) 2015-2021 The Project Lombok Authors.
  * 
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -279,7 +279,7 @@ abstract class EclipseGuavaSingularizer extends EclipseSingularizer {
 	protected abstract String getAddMethodName();
 	protected abstract String getAddAllTypeName();
 	
-	protected int getTypeArgumentsCount() {
+	@Override protected int getTypeArgumentsCount() {
 		return getArgumentSuffixes().size();
 	}
 }
diff --git a/src/core/lombok/eclipse/handlers/singulars/EclipseJavaUtilListSetSingularizer.java b/src/core/lombok/eclipse/handlers/singulars/EclipseJavaUtilListSetSingularizer.java
index deab4530..882b7adc 100755
--- a/src/core/lombok/eclipse/handlers/singulars/EclipseJavaUtilListSetSingularizer.java
+++ b/src/core/lombok/eclipse/handlers/singulars/EclipseJavaUtilListSetSingularizer.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2015-2020 The Project Lombok Authors.
+ * Copyright (C) 2015-2021 The Project Lombok Authors.
  * 
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -156,7 +156,7 @@ abstract class EclipseJavaUtilListSetSingularizer extends EclipseJavaUtilSingula
 		Annotation[] selfReturnAnnotations = generateSelfReturnAnnotations(deprecate, cfv, data.getSource());
 		Annotation[] copyToSetterAnnotations = copyAnnotations(md, findCopyableToBuilderSingularSetterAnnotations(data.getAnnotation().up()));
 		md.annotations = concat(selfReturnAnnotations, copyToSetterAnnotations, Annotation.class);
-
+		
 		if (returnStatement != null) createRelevantNonNullAnnotation(builderType, md);
 		data.setGeneratedByRecursive(md);
 		HandleNonNull.INSTANCE.fix(injectMethod(builderType, md));
@@ -194,9 +194,13 @@ abstract class EclipseJavaUtilListSetSingularizer extends EclipseJavaUtilSingula
 		Annotation[] selfReturnAnnotations = generateSelfReturnAnnotations(deprecate, cfv, data.getSource());
 		Annotation[] copyToSetterAnnotations = copyAnnotations(md, findCopyableToSetterAnnotations(data.getAnnotation().up()));
 		md.annotations = concat(selfReturnAnnotations, copyToSetterAnnotations, Annotation.class);
-
+		
 		if (returnStatement != null) createRelevantNonNullAnnotation(builderType, md);
 		data.setGeneratedByRecursive(md);
 		injectMethod(builderType, md);
 	}
+	
+	@Override protected int getTypeArgumentsCount() {
+		return 1;
+	}
 }
diff --git a/src/core/lombok/eclipse/handlers/singulars/EclipseJavaUtilMapSingularizer.java b/src/core/lombok/eclipse/handlers/singulars/EclipseJavaUtilMapSingularizer.java
index 1a40369d..d7b40261 100755
--- a/src/core/lombok/eclipse/handlers/singulars/EclipseJavaUtilMapSingularizer.java
+++ b/src/core/lombok/eclipse/handlers/singulars/EclipseJavaUtilMapSingularizer.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2015-2020 The Project Lombok Authors.
+ * Copyright (C) 2015-2021 The Project Lombok Authors.
  * 
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -349,4 +349,8 @@ public class EclipseJavaUtilMapSingularizer extends EclipseJavaUtilSingularizer
 			statements.addAll(createJavaUtilSimpleCreationAndFillStatements(data, builderType, true, true, false, true, "TreeMap", builderVariable));
 		}
 	}
+	
+	@Override protected int getTypeArgumentsCount() {
+		return 2;
+	}
 }