[fixes #1812] `@Singular` marked collections which nevertheless somehow ended up null would cause an NPE during `toBuilder()` invocations.

1 files changed, 10 insertions, 0 deletions

diff --git a/test/transform/resource/before/BuilderSingularToBuilderWithNull.java b/test/transform/resource/before/BuilderSingularToBuilderWithNull.java
new file mode 100644
index 00000000..92a102cb
--- /dev/null
+++ b/test/transform/resource/before/BuilderSingularToBuilderWithNull.java
@@ -0,0 +1,10 @@
+import lombok.Singular;
+
+@lombok.Builder(toBuilder = true)
+class BuilderSingularToBuilderWithNull {
+	@Singular private java.util.List<String> elems;
+	
+	public static void test() {
+		new BuilderSingularToBuilderWithNull(null).toBuilder();
+	}
+}