Removing from an empty JsonObjectBuilder may produce a NPE #167

.github/workflows/pr.yml

@@ -83,7 +83,7 @@ jobs:
       - name: Test
         uses: gradle/gradle-build-action@v2
         with:
-          gradle-version: 7.6.5
+          gradle-version: 8.7
           build-root-directory: tck-impl
           arguments: check -Pparsson.home=image/parsson-dist -Pparsson.impl=${{ matrix.test_suite }}
       - name: Upload test results

impl/src/main/java/org/eclipse/parsson/JsonObjectBuilderImpl.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2012, 2023 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012, 2026 Oracle and/or its affiliates. All rights reserved.
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -168,7 +168,9 @@ public JsonObjectBuilder addAll(JsonObjectBuilder builder) {
     @Override
     public JsonObjectBuilder remove(String name) {
         validateName(name);
-        this.valueMap.remove(name);
+        if (valueMap != null) {
+            valueMap.remove(name);
+        }
         return this;
     }
 

impl/src/test/java/org/eclipse/parsson/tests/JsonBuilderTest.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2012, 2024 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012, 2026 Oracle and/or its affiliates. All rights reserved.
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -95,6 +95,28 @@ void testJsonObjectMap() {
         JsonObjectTest.testPerson(copyPerson);
     }
 
+    @Test
+    void testRemoveFromEmptyObjectBuilder() {
+        JsonObject empty = Json.createObjectBuilder()
+                .remove("missing")
+                .build();
+
+        JsonObjectTest.testEmpty(empty);
+    }
+
+    @Test
+    void testRemoveFromObjectBuilderAfterBuild() {
+        JsonObjectBuilder builder = Json.createObjectBuilder()
+                .add("firstName", "John");
+
+        JsonObject first = builder.build();
+        builder.remove("firstName");
+        JsonObject empty = builder.build();
+
+        Assertions.assertEquals("John", first.getString("firstName"));
+        JsonObjectTest.testEmpty(empty);
+    }
+
     static Map<String, Object> buildPersonAsMap() {
         Map<String, Object> person = new HashMap<>();
         person.put("firstName", "John");