Fixed issue with PATCH incorrectly replacing entire complex attr

scim-core/src/main/java/org/apache/directory/scim/core/repository/DefaultPatchHandler.java

@@ -48,6 +48,7 @@
 import java.util.Map;
 import java.util.Optional;
 import java.util.function.Predicate;
+import org.apache.directory.scim.spec.schema.Schema.Attribute.Type;
 
 import static java.util.stream.Collectors.toList;
 
@@ -337,8 +338,16 @@ public void applySingleValue(Map<String, Object> sourceAsMap, Attribute attribut
         checkMutability(attribute.getAttribute(subAttributeName), parentValue.get(subAttributeName));
         parentValue.put(subAttributeName, value);
       } else {
-        checkMutability(attribute, sourceAsMap.get(attribute.getName()));
-        sourceAsMap.put(attribute.getName(), value);
+        Object currentValue = sourceAsMap.get(attribute.getName());
+        checkMutability(attribute, currentValue);
+        // PATCH on complex attributes should only replace the values given, leaving any not provided in the request untouched
+        if (attribute.getType() == Type.COMPLEX) {
+          Map<String, Object> newValue = ((Map<String, Object>) currentValue);
+          newValue.putAll((Map<String, Object>) value);
+          sourceAsMap.put(attribute.getName(), newValue);
+        } else {
+          sourceAsMap.put(attribute.getName(), value);
+        }
       }
     }
 

scim-core/src/test/java/org/apache/directory/scim/core/repository/PatchHandlerTest.java

@@ -56,6 +56,26 @@ public PatchHandlerTest() {
     this.patchHandler = new DefaultPatchHandler(schemaRegistry);
   }
 
+  @Test
+  public void applyReplaceComplexAttribute() {
+    // setup existing user
+    Name existingName = new Name();
+    existingName.setFamilyName("Family Name");
+    existingName.setGivenName("Given Name");
+    ScimUser user = user();
+    user.setName(existingName);
+
+    // setup patch ops
+    Map<String, String> newName = Map.of("familyName", "New Family Name");
+    PatchOperation op = patchOperation(REPLACE, "name", newName);
+
+    //execute
+    ScimUser updatedUser = patchHandler.apply(user, List.of(op));
+    assertThat(updatedUser.getName().getFamilyName()).isEqualTo("New Family Name");
+    // assert that PATCH did not update fields not provided in PatchOperation
+    assertThat(updatedUser.getName().getGivenName()).isNotNull();
+  }
+
   @Test
   public void applyReplaceUserName()  {
     String newUserName = "[email protected]";