Fix #4932 (#4937)

Author: cowtowncoder

release-notes/VERSION-2.x

@@ -31,6 +31,8 @@ Project: jackson-databind
  (reported by @dbachdev)
 #4922: Failing `@JsonMerge` with a custom Map
  (reported by @nlisker)
+#4932: Conversion of `MissingNode` throws `JsonProcessingException`
+ (reported by @ludgerb)
 
 2.18.2 (27-Nov-2024)
 

src/main/java/com/fasterxml/jackson/databind/ObjectMapper.java

@@ -4897,6 +4897,9 @@ protected Object _readValue(DeserializationConfig cfg, JsonParser p,
             result = _findRootDeserializer(ctxt, valueType).getNullValue(ctxt);
         } else if (t == JsonToken.END_ARRAY || t == JsonToken.END_OBJECT) {
             result = null;
+        } else if (t == JsonToken.NOT_AVAILABLE) {
+            // 28-Jan-2025, tatu: [databind#4932] Need to handle this case too
+            result = null;
         } else { // pointing to event other than null
             result = ctxt.readRootValue(p, valueType, _findRootDeserializer(ctxt, valueType), null);
         }
@@ -4921,6 +4924,9 @@ protected Object _readMapAndClose(JsonParser p0, JavaType valueType)
                 result = _findRootDeserializer(ctxt, valueType).getNullValue(ctxt);
             } else if (t == JsonToken.END_ARRAY || t == JsonToken.END_OBJECT) {
                 result = null;
+            } else if (t == JsonToken.NOT_AVAILABLE) {
+                // 28-Jan-2025, tatu: [databind#4932] Need to handle this case too
+                result = null;
             } else {
                 result = ctxt.readRootValue(p, valueType,
                         _findRootDeserializer(ctxt, valueType), null);

src/main/java/com/fasterxml/jackson/databind/ObjectReader.java

@@ -2095,6 +2095,9 @@ protected Object _bind(JsonParser p, Object valueToUpdate) throws IOException
             }
         } else if (t == JsonToken.END_ARRAY || t == JsonToken.END_OBJECT) {
             result = valueToUpdate;
+        } else if (t == JsonToken.NOT_AVAILABLE) {
+            // 28-Jan-2025, tatu: [databind#4932] Need to handle this case too
+            result = valueToUpdate;
         } else { // pointing to event other than null
             result = ctxt.readRootValue(p, _valueType, _findRootDeserializer(ctxt), _valueToUpdate);
         }
@@ -2121,6 +2124,9 @@ protected Object _bindAndClose(JsonParser p0) throws IOException
                 }
             } else if (t == JsonToken.END_ARRAY || t == JsonToken.END_OBJECT) {
                 result = _valueToUpdate;
+            } else if (t == JsonToken.NOT_AVAILABLE) {
+                // 28-Jan-2025, tatu: [databind#4932] Need to handle this case too
+                result = _valueToUpdate;
             } else {
                 result = ctxt.readRootValue(p, _valueType, _findRootDeserializer(ctxt), _valueToUpdate);
             }

src/test/java/com/fasterxml/jackson/databind/node/JsonNodeConversionsTest.java

@@ -419,4 +419,15 @@ public void testValueToTree() throws Exception
         assertEquals(wrapRootMapper.readValue(expected, Map.class), wrapRootMapper.readValue(wrapRootMapper.writeValueAsString(value), Map.class));
         assertEquals(wrapRootMapper.readValue(expected, Map.class), wrapRootMapper.readValue(wrapRootMapper.valueToTree(value).toString(), Map.class));
     }
+
+    // [databind#4932]: handling of `MissingNode` wrt conversions
+    @Test
+    public void treeToValueWithMissingNode4932() throws Exception {
+        assertNull(MAPPER.treeToValue(MAPPER.nullNode(), Object.class));
+        assertNull(MAPPER.treeToValue(MAPPER.missingNode(), Object.class));
+
+        ObjectReader r = MAPPER.readerFor(Object.class);
+        assertNull(r.treeToValue(MAPPER.nullNode(), Object.class));
+        assertNull(r.treeToValue(MAPPER.missingNode(), Object.class));
+    }
 }