trying to manually add (parts of) the infrastructure for @Singular @Builder stuff is now flagged as an error.

3 files changed, 65 insertions, 0 deletions

diff --git a/src/core/lombok/javac/handlers/HandleBuilder.java b/src/core/lombok/javac/handlers/HandleBuilder.java
index 24e9dee4..7bb0619f 100644
--- a/src/core/lombok/javac/handlers/HandleBuilder.java
+++ b/src/core/lombok/javac/handlers/HandleBuilder.java
@@ -227,6 +227,18 @@ public class HandleBuilder extends JavacAnnotationHandler<Builder> {
 			builderType = makeBuilderClass(tdParent, builderClassName, typeParams, ast);
 		} else {
 			sanityCheckForMethodGeneratingAnnotationsOnBuilderClass(builderType, annotationNode);
+			/* generate errors for @Singular BFDs that have one already defined node. */ {
+				for (BuilderFieldData bfd : builderFields) {
+					SingularData sd = bfd.singularData;
+					if (sd == null) continue;
+					JavacSingularizer singularizer = sd.getSingularizer();
+					if (singularizer == null) continue;
+					if (singularizer.checkForAlreadyExistingNodesAndGenerateError(builderType, sd)) {
+						bfd.singularData = null;
+					}
+				}
+			}
+
 		}
 		
 		for (BuilderFieldData bfd : builderFields) {
diff --git a/src/core/lombok/javac/handlers/JavacSingularsRecipes.java b/src/core/lombok/javac/handlers/JavacSingularsRecipes.java
index b21dbb0a..35bd66ed 100644
--- a/src/core/lombok/javac/handlers/JavacSingularsRecipes.java
+++ b/src/core/lombok/javac/handlers/JavacSingularsRecipes.java
@@ -25,6 +25,8 @@ import static lombok.javac.Javac.*;
 import static lombok.javac.handlers.JavacHandlerUtil.*;
 
 import java.io.IOException;
+import java.util.Arrays;
+import java.util.Collections;
 import java.util.HashMap;
 import java.util.Map;
 
@@ -38,7 +40,9 @@ import com.sun.source.tree.Tree.Kind;
 import com.sun.tools.javac.code.BoundKind;
 import com.sun.tools.javac.tree.JCTree;
 import com.sun.tools.javac.tree.JCTree.JCExpression;
+import com.sun.tools.javac.tree.JCTree.JCMethodDecl;
 import com.sun.tools.javac.tree.JCTree.JCStatement;
+import com.sun.tools.javac.tree.JCTree.JCVariableDecl;
 import com.sun.tools.javac.tree.JCTree.JCWildcard;
 import com.sun.tools.javac.util.Context;
 import com.sun.tools.javac.util.List;
@@ -137,6 +141,50 @@ public class JavacSingularsRecipes {
 	public static abstract class JavacSingularizer {
 		public abstract LombokImmutableList<String> getSupportedTypes();
 		
+		/** Checks if any of the to-be-generated nodes (fields, methods) already exist. If so, errors on these (singulars don't support manually writing some of it, and returns true). */
+		public boolean checkForAlreadyExistingNodesAndGenerateError(JavacNode builderType, SingularData data) {
+			for (JavacNode child : builderType.down()) {
+				switch (child.getKind()) {
+				case FIELD: {
+					JCVariableDecl field = (JCVariableDecl) child.get();
+					Name name = field.name;
+					if (name == null) break;
+					if (getGeneratedBy(field) != null) continue;
+					for (Name fieldToBeGenerated : listFieldsToBeGenerated(builderType, data)) {
+						if (!fieldToBeGenerated.equals(name)) continue;
+						child.addError("Manually adding a field that @Singular @Builder would generate is not supported. If you want to manually manage the builder aspect for this field/parameter, don't use @Singular.");
+						return true;
+					}
+					break;
+				}
+				case METHOD: {
+					JCMethodDecl method = (JCMethodDecl) child.get();
+					Name name = method.name;
+					if (name == null) break;
+					if (getGeneratedBy(method) != null) continue;
+					for (Name methodToBeGenerated : listMethodsToBeGenerated(builderType, data)) {
+						if (!methodToBeGenerated.equals(name)) continue;
+						child.addError("Manually adding a method that @Singular @Builder would generate is not supported. If you want to manually manage the builder aspect for this field/parameter, don't use @Singular.");
+						return true;
+					}
+					break;
+				}}
+			}
+			
+			return false;
+		}
+		
+		public java.util.List<Name> listFieldsToBeGenerated(JavacNode builderType, SingularData data) {
+			return Collections.singletonList(data.pluralName);
+		}
+		
+		public java.util.List<Name> listMethodsToBeGenerated(JavacNode builderType, SingularData data) {
+			Name p = data.pluralName;
+			Name s = data.singularName;
+			if (p.equals(s)) return Collections.singletonList(p);
+			return Arrays.asList(p, s);
+		}
+		
 		public abstract java.util.List<JavacNode> generateFields(SingularData data, JavacNode builderType, JCTree source);
 		public abstract void generateMethods(SingularData data, JavacNode builderType, JCTree source, boolean fluent, boolean chain);
 		public abstract void appendBuildCode(SingularData data, JavacNode builderType, JCTree source, ListBuffer<JCStatement> statements, Name targetVariableName);
diff --git a/src/core/lombok/javac/handlers/singulars/JavacJavaUtilMapSingularizer.java b/src/core/lombok/javac/handlers/singulars/JavacJavaUtilMapSingularizer.java
index acb1ae8f..21b25221 100644
--- a/src/core/lombok/javac/handlers/singulars/JavacJavaUtilMapSingularizer.java
+++ b/src/core/lombok/javac/handlers/singulars/JavacJavaUtilMapSingularizer.java
@@ -55,6 +55,11 @@ public class JavacJavaUtilMapSingularizer extends JavacJavaUtilSingularizer {
 		return LombokImmutableList.of("java.util.Map", "java.util.SortedMap", "java.util.NavigableMap");
 	}
 	
+	@Override public java.util.List<Name> listFieldsToBeGenerated(JavacNode builderType, SingularData data) {
+		String p = data.getPluralName().toString();
+		return Arrays.asList(builderType.toName(p + "$key"), builderType.toName(p + "$value"));
+	}
+	
 	@Override public java.util.List<JavacNode> generateFields(SingularData data, JavacNode builderType, JCTree source) {
 		JavacTreeMaker maker = builderType.getTreeMaker();