Add a failing test for yaml issue #306

Author: cowtowncoder

yaml/src/test/java/com/fasterxml/jackson/dataformat/yaml/failing/NameQuoting306Test.java

@@ -0,0 +1,23 @@
+package com.fasterxml.jackson.dataformat.yaml.failing;
+
+import java.util.Collections;
+import java.util.Map;
+
+import com.fasterxml.jackson.dataformat.yaml.ModuleTestBase;
+import com.fasterxml.jackson.dataformat.yaml.YAMLMapper;
+
+// for [dataformats-text#306]
+public class NameQuoting306Test extends ModuleTestBase
+{
+    private final YAMLMapper MAPPER = newObjectMapper();
+
+    // for [dataformats-text#306]
+    public void testComplexName() throws Exception
+    {
+        final String key = "SomeKey:\nOtherLine";
+        Map<?,?> input = Collections.singletonMap(key, 302);
+        final String doc = MAPPER.writeValueAsString(input);
+        Map<?,?> actual = MAPPER.readValue(doc, Map.class);
+        assertEquals(input, actual);
+    }
+}