Fix #63 (requires matching fix in jackson-databind 2.9.9)

Author: cowtowncoder

pom.xml

@@ -3,7 +3,7 @@
   <parent>
     <groupId>com.fasterxml.jackson</groupId>
     <artifactId>jackson-base</artifactId>
-    <version>2.9.8</version>
+    <version>2.9.9-SNAPSHOT</version>
   </parent>
   <groupId>com.fasterxml.jackson.dataformat</groupId>
   <artifactId>jackson-dataformats-text</artifactId>

release-notes/VERSION-2.x

@@ -8,6 +8,11 @@ Modules:
 === Releases ===
 ------------------------------------------------------------------------
 
+2.9.9 (not yet released)
+
+#63: `null` Object Id serialized as anchor for YAML
+ (reported by jflefebvre06@github)
+
 2.9.8 (15-Dec-2018)
 
 #99: `YamlGenerator` closes the target stream when configured not to

yaml/src/test/java/com/fasterxml/jackson/dataformat/yaml/failing/ObjectId63Test.java

@@ -0,0 +1,52 @@
+package com.fasterxml.jackson.dataformat.yaml.failing;
+
+import com.fasterxml.jackson.annotation.JsonIdentityInfo;
+import com.fasterxml.jackson.annotation.ObjectIdGenerators;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.dataformat.yaml.*;
+
+// for [dataformats-text#63], problem with YAML, Object Ids
+public class ObjectId63Test extends ModuleTestBase
+{
+    @JsonIdentityInfo(generator = ObjectIdGenerators.PropertyGenerator.class, property = "id")
+    public static class SimplePojo {
+        String id;
+        String value;
+
+        public String getId() {
+            return this.id;
+        }
+
+        public void setId(final String newId) {
+            this.id = newId;
+        }
+
+        public String getValue() {
+            return this.value;
+        }
+
+        public void setValue(final String newValue) {
+            this.value = newValue;
+        }
+    }
+
+    private final ObjectMapper MAPPER = newObjectMapper();
+
+    public void testIssue63() throws Exception
+    {
+        final SimplePojo simplePojoWithId = new SimplePojo();
+        simplePojoWithId.setId("myId");
+        simplePojoWithId.setValue("Value");
+
+        final SimplePojo simplePojoWithoutId = new SimplePojo();
+        simplePojoWithoutId.setValue("Value");
+
+        assertEquals("---\n&myId id: \"myId\"\nvalue: \"Value\"",
+                MAPPER.writeValueAsString(simplePojoWithId).trim());
+
+        // `null` object id is not to be written as anchor but skipped; property itself
+        // follows regular inclusion rules.
+        assertEquals("---\nid: null\nvalue: \"Value\"",
+                MAPPER.writeValueAsString(simplePojoWithoutId).trim());
+    }
+}