Minor improvement to validity checking, wrt #2977

Author: cowtowncoder

src/main/java/com/fasterxml/jackson/databind/deser/BasicDeserializerFactory.java

@@ -880,11 +880,8 @@ protected void _addExplicitPropertyCreator(DeserializationContext ctxt,
                     */
                 }
                 name = candidate.findImplicitParamName(i);
-                // Must be injectable or have name; without either won't work
-                if ((name == null) && (injectId == null)) {
-                    ctxt.reportBadTypeDefinition(beanDesc,
-"Argument #%d has no property name, is not Injectable: can not use as Creator %s", i, candidate);
-                }
+                _validateNamedPropertyParameter(ctxt, beanDesc, candidate, i,
+                        name, injectId);
             }
             properties[i] = constructCreatorProperty(ctxt, beanDesc, name, i, param, injectId);
         }
@@ -949,6 +946,11 @@ protected void _addExplicitAnyCreator(DeserializationContext ctxt,
             // 13-Sep-2020, tatu: since we are configured to prefer Properties-style,
             //    any name (explicit OR implicit does):
             paramName = candidate.paramName(0);
+            // [databind#2977]: Need better exception if name missing
+            if (paramName == null) {
+                _validateNamedPropertyParameter(ctxt, beanDesc, candidate, 0,
+                        paramName, injectId);
+            }
             break;
 
         case REQUIRE_MODE:
@@ -1126,6 +1128,24 @@ protected boolean _handleSingleArgumentCreator(CreatorCollector creators,
         return false;
     }
 
+    // Helper method to check that parameter of Property-based creator either
+    // has name or is marked as Injectable
+    //
+    // @since 2.12.1
+    protected void _validateNamedPropertyParameter(DeserializationContext ctxt,
+            BeanDescription beanDesc,
+            CreatorCandidate candidate, int paramIndex,
+            PropertyName name, JacksonInject.Value injectId)
+        throws JsonMappingException
+    {
+        // Must be injectable or have name; without either won't work
+        if ((name == null) && (injectId == null)) {
+            ctxt.reportBadTypeDefinition(beanDesc,
+"Argument #%d of constructor %s has no property name (and is not Injectable): can not use as property-based Creator",
+paramIndex, candidate);
+        }
+    }
+
     // 01-Dec-2016, tatu: As per [databind#265] we cannot yet support passing
     //   of unwrapped values through creator properties, so fail fast
     protected void _reportUnwrappedCreatorProperty(DeserializationContext ctxt,

src/test/java/com/fasterxml/jackson/databind/deser/creators/TestCreatorNullPrimitives.java

@@ -2,6 +2,7 @@
 
 import com.fasterxml.jackson.annotation.JsonCreator;
 import com.fasterxml.jackson.annotation.JsonProperty;
+
 import com.fasterxml.jackson.databind.BaseMapTest;
 import com.fasterxml.jackson.databind.DeserializationFeature;
 import com.fasterxml.jackson.databind.JsonMappingException;
@@ -39,7 +40,7 @@ private NestedJsonEntity(@JsonProperty("entity") JsonEntity entity) {
     /**********************************************************
      */
 
-    private final ObjectMapper MAPPER = sharedMapper();
+    private final ObjectMapper MAPPER = newJsonMapper();
 
     // [databind#2101]: ensure that the property is included in the path
     public void testCreatorNullPrimitive() throws IOException {