[fixes #1324] toBuilder with @Singular marked collections that are null no longer throws NPE.

8 files changed, 89 insertions, 148 deletions

diff --git a/doc/changelog.markdown b/doc/changelog.markdown
index 220e0dc0..e98ae4b6 100644
--- a/doc/changelog.markdown
+++ b/doc/changelog.markdown
@@ -5,6 +5,7 @@ Lombok Changelog
 * PLATFORM: Support for Eclipse Photon. [Issue #1831](https://github.com/rzwitserloot/lombok/issues/1831)
 * FEATURE: The `@FieldNameConstants` feature has been completely redesigned. [Issue #1774](https://github.com/rzwitserloot/lombok/issues/1774) [FieldNameConstants documentation](https://projectlombok.org/features/experimental/FieldNameConstants)
 * FEATURE: Lombok's `@NonNull` annotation can now be used on types (annotation on types has been introduced in JDK 8). `@Builder`'s `@Singular` annotation now properly deals with annotations on the generics type on the collection: `@Singular List<@NonNull String> names;` now does the right thing.
+* FEATURE: You can now mix `@SuperBuilder` and `toBuilder`, and `toBuilder` no longer throws `NullPointerException` if an `@Singular`-marked collection field is `null`. [Issue #1324](https://github.com/rzwitserloot/lombok/issues/1324)
 * BREAKING CHANGE: Lombok will now always copy specific annotations around (from field to getter, from field to builder 'setter', etcetera): A specific curated list of known annotations where that is the right thing to do (generally, `@NonNull` style annotations from various libraries), as well as any annotations you explicitly list in the `lombok.copyableAnnotations` config key in your `lombok.config` file. Also, lombok is more consistent about copying these annotations. (Previous behaviour: Lombok used to copy any annotation whose simple name was `NonNull`, `Nullable`, or `CheckForNull`). [Issue #1570](https://github.com/rzwitserloot/lombok/issues/1570) and [Issue #1634](https://github.com/rzwitserloot/lombok/issues/1634)
 * BUGFIX: When using lombok to compile modularized (`module-info.java`-style) code, if the module name has dots in it, it wouldn't work. [Issue #1808](https://github.com/rzwitserloot/lombok/issues/1808)
 * BUGFIX: Errors about lombok not reading a module providing `org.mapstruct.ap.spi` when trying to use lombok in jigsaw-mode on JDK 11. [Issue #1806](https://github.com/rzwitserloot/lombok/issues/1806)
diff --git a/src/core/lombok/eclipse/handlers/HandleBuilder.java b/src/core/lombok/eclipse/handlers/HandleBuilder.java
index 09765efc..e22b4ed2 100644
--- a/src/core/lombok/eclipse/handlers/HandleBuilder.java
+++ b/src/core/lombok/eclipse/handlers/HandleBuilder.java
@@ -25,6 +25,7 @@ import static lombok.eclipse.Eclipse.*;
 import static lombok.core.handlers.HandlerUtil.*;
 import static lombok.eclipse.handlers.EclipseHandlerUtil.*;
 
+import java.lang.reflect.Modifier;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
@@ -46,6 +47,7 @@ import org.eclipse.jdt.internal.compiler.ast.FalseLiteral;
 import org.eclipse.jdt.internal.compiler.ast.FieldDeclaration;
 import org.eclipse.jdt.internal.compiler.ast.FieldReference;
 import org.eclipse.jdt.internal.compiler.ast.IfStatement;
+import org.eclipse.jdt.internal.compiler.ast.LocalDeclaration;
 import org.eclipse.jdt.internal.compiler.ast.MessageSend;
 import org.eclipse.jdt.internal.compiler.ast.MethodDeclaration;
 import org.eclipse.jdt.internal.compiler.ast.NullLiteral;
@@ -502,15 +504,12 @@ public class HandleBuilder extends EclipseAnnotationHandler<Builder> {
 		}
 	}
 	
-	private static final char[] EMPTY_LIST = "emptyList".toCharArray();
+	private static final char[] BUILDER_TEMP_VAR = {'b', 'u', 'i', 'l', 'd', 'e', 'r'};
 	private MethodDeclaration generateToBuilderMethod(String methodName, String builderClassName, EclipseNode type, TypeParameter[] typeParams, List<BuilderFieldData> builderFields, boolean fluent, ASTNode source) {
-		// return new ThingieBuilder<A, B>().setA(this.a).setB(this.b);
-		
 		int pS = source.sourceStart, pE = source.sourceEnd;
 		long p = (long) pS << 32 | pE;
 		
-		MethodDeclaration out = new MethodDeclaration(
-				((CompilationUnitDeclaration) type.top().get()).compilationResult);
+		MethodDeclaration out = new MethodDeclaration(((CompilationUnitDeclaration) type.top().get()).compilationResult);
 		out.selector = methodName.toCharArray();
 		out.modifiers = ClassFileConstants.AccPublic;
 		out.bits |= ECLIPSE_DO_NOT_TOUCH_FLAG;
@@ -519,6 +518,7 @@ public class HandleBuilder extends EclipseAnnotationHandler<Builder> {
 		invoke.type = namePlusTypeParamsToTypeReference(builderClassName.toCharArray(), typeParams, p);
 		
 		Expression receiver = invoke;
+		List<Statement> statements = null;
 		for (BuilderFieldData bfd : builderFields) {
 			char[] setterName = fluent ? bfd.name : HandlerUtil.buildAccessorName("set", new String(bfd.name)).toCharArray();
 			MessageSend ms = new MessageSend();
@@ -542,22 +542,34 @@ public class HandleBuilder extends EclipseAnnotationHandler<Builder> {
 					tgt[i] = obtainExpr;
 				}
 			}
+			
+			ms.selector = setterName;
 			if (bfd.singularData == null) {
 				ms.arguments = tgt;
+				ms.receiver = receiver;
+				receiver = ms;
 			} else {
-				Expression ifNull = new EqualExpression(tgt[0], new NullLiteral(0, 0), OperatorIds.EQUAL_EQUAL);
-				MessageSend emptyList = new MessageSend();
-				emptyList.receiver = generateQualifiedNameRef(source, TypeConstants.JAVA, TypeConstants.UTIL, "Collections".toCharArray());
-				emptyList.selector = EMPTY_LIST;
-				emptyList.typeArguments = copyTypes(bfd.singularData.getTypeArgs().toArray(new TypeReference[0]));
-				ms.arguments = new Expression[] {new ConditionalExpression(ifNull, emptyList, tgt[1])};
+				ms.arguments = new Expression[] {tgt[1]};
+				ms.receiver = new SingleNameReference(BUILDER_TEMP_VAR, p);
+				EqualExpression isNotNull = new EqualExpression(tgt[0], new NullLiteral(pS, pE), OperatorIds.NOT_EQUAL);
+				if (statements == null) statements = new ArrayList<Statement>();
+				statements.add(new IfStatement(isNotNull, ms, pS, pE));
 			}
-			ms.receiver = receiver;
-			ms.selector = setterName;
-			receiver = ms;
 		}
 		
-		out.statements = new Statement[] {new ReturnStatement(receiver, pS, pE)};
+		if (statements != null) {
+			out.statements = new Statement[statements.size() + 2];
+			for (int i = 0; i < statements.size(); i++) out.statements[i + 1] = statements.get(i);
+			LocalDeclaration b = new LocalDeclaration(BUILDER_TEMP_VAR, pS, pE);
+			out.statements[0] = b;
+			b.modifiers |= Modifier.FINAL;
+			b.type = namePlusTypeParamsToTypeReference(builderClassName.toCharArray(), typeParams, p);
+			b.type.sourceStart = pS; b.type.sourceEnd = pE;
+			b.initialization = receiver;
+			out.statements[out.statements.length - 1] = new ReturnStatement(new SingleNameReference(BUILDER_TEMP_VAR, p), pS, pE);
+		} else {
+			out.statements = new Statement[] {new ReturnStatement(receiver, pS, pE)};
+		}
 		
 		out.traverse(new SetGeneratedByVisitor(source), ((TypeDeclaration) type.get()).scope);
 		return out;
@@ -617,7 +629,7 @@ public class HandleBuilder extends EclipseAnnotationHandler<Builder> {
 				inv.typeArguments = typeParameterNames(((TypeDeclaration) type.get()).typeParameters);
 				
 				args.add(new ConditionalExpression(
-					new SingleNameReference(bfd.nameOfSetFlag,  0L),
+					new SingleNameReference(bfd.nameOfSetFlag, 0L),
 					new SingleNameReference(bfd.name, 0L),
 					inv));
 			} else {
diff --git a/src/core/lombok/javac/handlers/HandleBuilder.java b/src/core/lombok/javac/handlers/HandleBuilder.java
index bc1a8072..c5c1e1ca 100644
--- a/src/core/lombok/javac/handlers/HandleBuilder.java
+++ b/src/core/lombok/javac/handlers/HandleBuilder.java
@@ -484,6 +484,7 @@ public class HandleBuilder extends JavacAnnotationHandler<Builder> {
 		sb.append("__ERR__");
 	}
 	
+	private static final String BUILDER_TEMP_VAR = "builder";
 	private JCMethodDecl generateToBuilderMethod(String toBuilderMethodName, String builderClassName, JavacNode type, List<JCTypeParameter> typeParams, java.util.List<BuilderFieldData> builderFields, boolean fluent, JCAnnotation ast) {
 		// return new ThingieBuilder<A, B>().setA(this.a).setB(this.b);
 		JavacTreeMaker maker = type.getTreeMaker();
@@ -495,6 +496,7 @@ public class HandleBuilder extends JavacAnnotationHandler<Builder> {
 		
 		JCExpression call = maker.NewClass(null, List.<JCExpression>nil(), namePlusTypeParamsToTypeReference(maker, type.toName(builderClassName), typeParams), List.<JCExpression>nil(), null);
 		JCExpression invoke = call;
+		ListBuffer<JCStatement> statements = new ListBuffer<JCStatement>();
 		for (BuilderFieldData bfd : builderFields) {
 			Name setterName = fluent ? bfd.name : type.toName(HandlerUtil.buildAccessorName("set", bfd.name.toString()));
 			JCExpression[] tgt = new JCExpression[bfd.singularData == null ? 1 : 2];
@@ -519,18 +521,21 @@ public class HandleBuilder extends JavacAnnotationHandler<Builder> {
 			JCExpression arg;
 			if (bfd.singularData == null) {
 				arg = tgt[0];
+				invoke = maker.Apply(List.<JCExpression>nil(), maker.Select(invoke, setterName), List.of(arg));
 			} else {
-				JCExpression eqNull = maker.Binary(CTC_EQUAL, tgt[0], maker.Literal(CTC_BOT, null));
-				List<JCExpression> tas = cloneTypes(maker, bfd.singularData.getTypeArgs(), ast, type.getContext());
-				JCExpression emptyList = maker.Apply(tas, chainDots(type, "java", "util", "Collections", "emptyList"), List.<JCExpression>nil());
-				arg = maker.Conditional(eqNull, emptyList, tgt[1]);
+				JCExpression isNotNull = maker.Binary(CTC_NOT_EQUAL, tgt[0], maker.Literal(CTC_BOT, null));
+				JCExpression invokeBuilder = maker.Apply(List.<JCExpression>nil(), maker.Select(maker.Ident(type.toName(BUILDER_TEMP_VAR)), setterName), List.<JCExpression>of(tgt[1]));
+				statements.append(maker.If(isNotNull, maker.Exec(invokeBuilder), null));
 			}
-			
-			invoke = maker.Apply(List.<JCExpression>nil(), maker.Select(invoke, setterName), List.of(arg));
 		}
-		JCStatement statement = maker.Return(invoke);
-		
-		JCBlock body = maker.Block(0, List.<JCStatement>of(statement));
+		if (!statements.isEmpty()) {
+			JCExpression tempVarType = namePlusTypeParamsToTypeReference(maker, type.toName(builderClassName), typeParams);
+			statements.prepend(maker.VarDef(maker.Modifiers(Flags.FINAL), type.toName(BUILDER_TEMP_VAR), tempVarType, invoke));
+			statements.append(maker.Return(maker.Ident(type.toName(BUILDER_TEMP_VAR))));
+		} else {
+			statements.append(maker.Return(invoke));
+		}
+		JCBlock body = maker.Block(0, statements.toList());
 		return maker.MethodDef(maker.Modifiers(Flags.PUBLIC), type.toName(toBuilderMethodName), namePlusTypeParamsToTypeReference(maker, type.toName(builderClassName), typeParams), List.<JCTypeParameter>nil(), List.<JCVariableDecl>nil(), List.<JCExpression>nil(), body, null);
 	}
 	
diff --git a/test/transform/resource/after-delombok/BuilderSingularToBuilderWithNull.java b/test/transform/resource/after-delombok/BuilderSingularToBuilderWithNull.java
index b0563858..96ffd2dc 100644
--- a/test/transform/resource/after-delombok/BuilderSingularToBuilderWithNull.java
+++ b/test/transform/resource/after-delombok/BuilderSingularToBuilderWithNull.java
@@ -58,6 +58,8 @@ class BuilderSingularToBuilderWithNull {
 	}
 	@java.lang.SuppressWarnings("all")
 	public BuilderSingularToBuilderWithNullBuilder toBuilder() {
-		return new BuilderSingularToBuilderWithNullBuilder().elems(this.elems == null ? java.util.Collections.<String>emptyList() : this.elems);
+		final BuilderSingularToBuilderWithNullBuilder builder = new BuilderSingularToBuilderWithNullBuilder();
+		if (this.elems != null) builder.elems(this.elems);
+		return builder;
 	}
 }
diff --git a/test/transform/resource/after-delombok/BuilderWithToBuilder.java b/test/transform/resource/after-delombok/BuilderWithToBuilder.java
index 8615a40b..53256107 100644
--- a/test/transform/resource/after-delombok/BuilderWithToBuilder.java
+++ b/test/transform/resource/after-delombok/BuilderWithToBuilder.java
@@ -86,7 +86,9 @@ class BuilderWithToBuilder<T> {
 	}
 	@java.lang.SuppressWarnings("all")
 	public BuilderWithToBuilderBuilder<T> toBuilder() {
-		return new BuilderWithToBuilderBuilder<T>().one(this.mOne).two(this.mTwo).foo(BuilderWithToBuilder.rrr(this)).bars(this.bars == null ? java.util.Collections.<T>emptyList() : this.bars);
+		final BuilderWithToBuilderBuilder<T> builder = new BuilderWithToBuilderBuilder<T>().one(this.mOne).two(this.mTwo).foo(BuilderWithToBuilder.rrr(this));
+		if (this.bars != null) builder.bars(this.bars);
+		return builder;
 	}
 }
 class ConstructorWithToBuilder<T> {
@@ -94,15 +96,17 @@ class ConstructorWithToBuilder<T> {
 	private String mTwo;
 	private T foo;
 	@lombok.Singular
-	private List<T> bars;
-	public ConstructorWithToBuilder(String mOne, T bar) {
+	private com.google.common.collect.ImmutableList<T> bars;
+	public ConstructorWithToBuilder(String mOne, T baz, com.google.common.collect.ImmutableList<T> bars) {
 	}
 	@java.lang.SuppressWarnings("all")
 	public static class ConstructorWithToBuilderBuilder<T> {
 		@java.lang.SuppressWarnings("all")
 		private String mOne;
 		@java.lang.SuppressWarnings("all")
-		private T bar;
+		private T baz;
+		@java.lang.SuppressWarnings("all")
+		private com.google.common.collect.ImmutableList<T> bars;
 		@java.lang.SuppressWarnings("all")
 		ConstructorWithToBuilderBuilder() {
 		}
@@ -112,18 +116,23 @@ class ConstructorWithToBuilder<T> {
 			return this;
 		}
 		@java.lang.SuppressWarnings("all")
-		public ConstructorWithToBuilderBuilder<T> bar(final T bar) {
-			this.bar = bar;
+		public ConstructorWithToBuilderBuilder<T> baz(final T baz) {
+			this.baz = baz;
+			return this;
+		}
+		@java.lang.SuppressWarnings("all")
+		public ConstructorWithToBuilderBuilder<T> bars(final com.google.common.collect.ImmutableList<T> bars) {
+			this.bars = bars;
 			return this;
 		}
 		@java.lang.SuppressWarnings("all")
 		public ConstructorWithToBuilder<T> build() {
-			return new ConstructorWithToBuilder<T>(mOne, bar);
+			return new ConstructorWithToBuilder<T>(mOne, baz, bars);
 		}
 		@java.lang.Override
 		@java.lang.SuppressWarnings("all")
 		public java.lang.String toString() {
-			return "ConstructorWithToBuilder.ConstructorWithToBuilderBuilder(mOne=" + this.mOne + ", bar=" + this.bar + ")";
+			return "ConstructorWithToBuilder.ConstructorWithToBuilderBuilder(mOne=" + this.mOne + ", baz=" + this.baz + ", bars=" + this.bars + ")";
 		}
 	}
 	@java.lang.SuppressWarnings("all")
@@ -132,54 +141,6 @@ class ConstructorWithToBuilder<T> {
 	}
 	@java.lang.SuppressWarnings("all")
 	public ConstructorWithToBuilderBuilder<T> toBuilder() {
-		return new ConstructorWithToBuilderBuilder<T>().mOne(this.mOne).bar(this.foo);
+		return new ConstructorWithToBuilderBuilder<T>().mOne(this.mOne).baz(this.foo).bars(this.bars);
 	}
-}
-class StaticWithToBuilder<T, K> {
-	private String mOne;
-	private String mTwo;
-	private T foo;
-	private K bar;
-	@lombok.Singular
-	private List<T> bars;
-	public static <Z> StaticWithToBuilder<Z, String> test(String mOne, Z bar) {
-		return new StaticWithToBuilder<Z, String>();
-	}
-	@java.lang.SuppressWarnings("all")
-	public static class StaticWithToBuilderBuilder<Z> {
-		@java.lang.SuppressWarnings("all")
-		private String mOne;
-		@java.lang.SuppressWarnings("all")
-		private Z bar;
-		@java.lang.SuppressWarnings("all")
-		StaticWithToBuilderBuilder() {
-		}
-		@java.lang.SuppressWarnings("all")
-		public StaticWithToBuilderBuilder<Z> mOne(final String mOne) {
-			this.mOne = mOne;
-			return this;
-		}
-		@java.lang.SuppressWarnings("all")
-		public StaticWithToBuilderBuilder<Z> bar(final Z bar) {
-			this.bar = bar;
-			return this;
-		}
-		@java.lang.SuppressWarnings("all")
-		public StaticWithToBuilder<Z, String> build() {
-			return StaticWithToBuilder.<Z>test(mOne, bar);
-		}
-		@java.lang.Override
-		@java.lang.SuppressWarnings("all")
-		public java.lang.String toString() {
-			return "StaticWithToBuilder.StaticWithToBuilderBuilder(mOne=" + this.mOne + ", bar=" + this.bar + ")";
-		}
-	}
-	@java.lang.SuppressWarnings("all")
-	public static <Z> StaticWithToBuilderBuilder<Z> builder() {
-		return new StaticWithToBuilderBuilder<Z>();
-	}
-	@java.lang.SuppressWarnings("all")
-	public StaticWithToBuilderBuilder<T> toBuilder() {
-		return new StaticWithToBuilderBuilder<T>().mOne(this.mOne).bar(this.foo);
-	}
-}
+}
\ No newline at end of file
diff --git a/test/transform/resource/after-ecj/BuilderSingularToBuilderWithNull.java b/test/transform/resource/after-ecj/BuilderSingularToBuilderWithNull.java
index bbbf9268..ccd6335a 100644
--- a/test/transform/resource/after-ecj/BuilderSingularToBuilderWithNull.java
+++ b/test/transform/resource/after-ecj/BuilderSingularToBuilderWithNull.java
@@ -52,6 +52,9 @@ import lombok.Singular;
     return new BuilderSingularToBuilderWithNullBuilder();
   }
   public @java.lang.SuppressWarnings("all") BuilderSingularToBuilderWithNullBuilder toBuilder() {
-    return new BuilderSingularToBuilderWithNullBuilder().elems(((this.elems == null) ? java.util.Collections.<String>emptyList() : this.elems));
+    final BuilderSingularToBuilderWithNullBuilder builder = new BuilderSingularToBuilderWithNullBuilder();
+    if ((this.elems != null))
+        builder.elems(this.elems);
+    return builder;
   }
-}
+}
\ No newline at end of file
diff --git a/test/transform/resource/after-ecj/BuilderWithToBuilder.java b/test/transform/resource/after-ecj/BuilderWithToBuilder.java
index 636dc42d..420f1583 100644
--- a/test/transform/resource/after-ecj/BuilderWithToBuilder.java
+++ b/test/transform/resource/after-ecj/BuilderWithToBuilder.java
@@ -74,13 +74,17 @@ import lombok.Builder;
     return new BuilderWithToBuilderBuilder<T>();
   }
   public @java.lang.SuppressWarnings("all") BuilderWithToBuilderBuilder<T> toBuilder() {
-    return new BuilderWithToBuilderBuilder<T>().one(this.mOne).two(this.mTwo).foo(BuilderWithToBuilder.rrr(this)).bars(((this.bars == null) ? java.util.Collections.<T>emptyList() : this.bars));
+    final BuilderWithToBuilderBuilder<T> builder = new BuilderWithToBuilderBuilder<T>().one(this.mOne).two(this.mTwo).foo(BuilderWithToBuilder.rrr(this));
+    if ((this.bars != null))
+        builder.bars(this.bars);
+    return builder;
   }
 }
 @lombok.experimental.Accessors(prefix = "m") class ConstructorWithToBuilder<T> {
   public static @java.lang.SuppressWarnings("all") class ConstructorWithToBuilderBuilder<T> {
     private @java.lang.SuppressWarnings("all") String mOne;
-    private @java.lang.SuppressWarnings("all") T bar;
+    private @java.lang.SuppressWarnings("all") T baz;
+    private @java.lang.SuppressWarnings("all") com.google.common.collect.ImmutableList<T> bars;
     @java.lang.SuppressWarnings("all") ConstructorWithToBuilderBuilder() {
       super();
     }
@@ -88,68 +92,32 @@ import lombok.Builder;
       this.mOne = mOne;
       return this;
     }
-    public @java.lang.SuppressWarnings("all") ConstructorWithToBuilderBuilder<T> bar(final T bar) {
-      this.bar = bar;
+    public @java.lang.SuppressWarnings("all") ConstructorWithToBuilderBuilder<T> baz(final T baz) {
+      this.baz = baz;
+      return this;
+    }
+    public @java.lang.SuppressWarnings("all") ConstructorWithToBuilderBuilder<T> bars(final com.google.common.collect.ImmutableList<T> bars) {
+      this.bars = bars;
       return this;
     }
     public @java.lang.SuppressWarnings("all") ConstructorWithToBuilder<T> build() {
-      return new ConstructorWithToBuilder<T>(mOne, bar);
+      return new ConstructorWithToBuilder<T>(mOne, baz, bars);
     }
     public @java.lang.Override @java.lang.SuppressWarnings("all") java.lang.String toString() {
-      return (((("ConstructorWithToBuilder.ConstructorWithToBuilderBuilder(mOne=" + this.mOne) + ", bar=") + this.bar) + ")");
+      return (((((("ConstructorWithToBuilder.ConstructorWithToBuilderBuilder(mOne=" + this.mOne) + ", baz=") + this.baz) + ", bars=") + this.bars) + ")");
     }
   }
   private String mOne;
   private String mTwo;
   private T foo;
-  private @lombok.Singular List<T> bars;
-  public @Builder(toBuilder = true) ConstructorWithToBuilder(String mOne, @Builder.ObtainVia(field = "foo") T bar) {
+  private @lombok.Singular com.google.common.collect.ImmutableList<T> bars;
+  public @Builder(toBuilder = true) ConstructorWithToBuilder(String mOne, @Builder.ObtainVia(field = "foo") T baz, com.google.common.collect.ImmutableList<T> bars) {
     super();
   }
   public static @java.lang.SuppressWarnings("all") <T>ConstructorWithToBuilderBuilder<T> builder() {
     return new ConstructorWithToBuilderBuilder<T>();
   }
   public @java.lang.SuppressWarnings("all") ConstructorWithToBuilderBuilder<T> toBuilder() {
-    return new ConstructorWithToBuilderBuilder<T>().mOne(this.mOne).bar(this.foo);
-  }
-}
-@lombok.experimental.Accessors(prefix = "m") class StaticWithToBuilder<T, K> {
-  public static @java.lang.SuppressWarnings("all") class StaticWithToBuilderBuilder<Z> {
-    private @java.lang.SuppressWarnings("all") String mOne;
-    private @java.lang.SuppressWarnings("all") Z bar;
-    @java.lang.SuppressWarnings("all") StaticWithToBuilderBuilder() {
-      super();
-    }
-    public @java.lang.SuppressWarnings("all") StaticWithToBuilderBuilder<Z> mOne(final String mOne) {
-      this.mOne = mOne;
-      return this;
-    }
-    public @java.lang.SuppressWarnings("all") StaticWithToBuilderBuilder<Z> bar(final Z bar) {
-      this.bar = bar;
-      return this;
-    }
-    public @java.lang.SuppressWarnings("all") StaticWithToBuilder<Z, String> build() {
-      return StaticWithToBuilder.<Z>test(mOne, bar);
-    }
-    public @java.lang.Override @java.lang.SuppressWarnings("all") java.lang.String toString() {
-      return (((("StaticWithToBuilder.StaticWithToBuilderBuilder(mOne=" + this.mOne) + ", bar=") + this.bar) + ")");
-    }
-  }
-  private String mOne;
-  private String mTwo;
-  private T foo;
-  private K bar;
-  private @lombok.Singular List<T> bars;
-  StaticWithToBuilder() {
-    super();
-  }
-  public static @Builder(toBuilder = true) <Z>StaticWithToBuilder<Z, String> test(String mOne, @Builder.ObtainVia(field = "foo") Z bar) {
-    return new StaticWithToBuilder<Z, String>();
-  }
-  public static @java.lang.SuppressWarnings("all") <Z>StaticWithToBuilderBuilder<Z> builder() {
-    return new StaticWithToBuilderBuilder<Z>();
-  }
-  public @java.lang.SuppressWarnings("all") StaticWithToBuilderBuilder<T> toBuilder() {
-    return new StaticWithToBuilderBuilder<T>().mOne(this.mOne).bar(this.foo);
+    return new ConstructorWithToBuilderBuilder<T>().mOne(this.mOne).baz(this.foo).bars(this.bars);
   }
 }
diff --git a/test/transform/resource/before/BuilderWithToBuilder.java b/test/transform/resource/before/BuilderWithToBuilder.java
index 63e16ae8..50938ab2 100644
--- a/test/transform/resource/before/BuilderWithToBuilder.java
+++ b/test/transform/resource/before/BuilderWithToBuilder.java
@@ -13,19 +13,8 @@ class BuilderWithToBuilder<T> {
 class ConstructorWithToBuilder<T> {
 	private String mOne, mTwo;
 	private T foo;
-	@lombok.Singular private List<T> bars;
-	@Builder(toBuilder = true)
-	public ConstructorWithToBuilder(String mOne, @Builder.ObtainVia(field = "foo") T bar) {
-	}
-}
-@lombok.experimental.Accessors(prefix = "m")
-class StaticWithToBuilder<T, K> {
-	private String mOne, mTwo;
-	private T foo;
-	private K bar;
-	@lombok.Singular private List<T> bars;
+	@lombok.Singular private com.google.common.collect.ImmutableList<T> bars;
 	@Builder(toBuilder = true)
-	public static <Z> StaticWithToBuilder<Z, String> test(String mOne, @Builder.ObtainVia(field = "foo") Z bar) {
-		return new StaticWithToBuilder<Z, String>();
+	public ConstructorWithToBuilder(String mOne, @Builder.ObtainVia(field = "foo") T baz, com.google.common.collect.ImmutableList<T> bars) {
 	}
 }