Add failing test for #251

ion/src/test/java/com/fasterxml/jackson/dataformat/ion/failing/IonTimestampDeser251Test.java

@@ -0,0 +1,47 @@
+package com.fasterxml.jackson.dataformat.ion.failing;
+
+import org.junit.Test;
+
+import com.fasterxml.jackson.annotation.JsonCreator;
+import com.fasterxml.jackson.annotation.JsonProperty;
+import com.fasterxml.jackson.databind.DeserializationFeature;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.dataformat.ion.IonObjectMapper;
+import com.fasterxml.jackson.dataformat.ion.ionvalue.IonValueModule;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
+
+// For [dataformats-binary#251]
+public class IonTimestampDeser251Test
+{
+    static class Message {
+        final String message;
+        final Integer count;
+
+        @JsonCreator
+        public Message(@JsonProperty("message") String message,
+                       @JsonProperty("count") Integer count) {
+            this.message = message;
+            this.count = count;
+        }
+
+        public String getMessage() {
+            return message;
+        }
+    }
+
+    private final ObjectMapper ION_MAPPER = IonObjectMapper.builder()
+            .addModule(new IonValueModule())
+            .configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false)
+            .build();
+
+    // [dataformats-binary#251]
+    @Test
+    public void testTimestampDeserWithBuffering() throws Exception {
+        String ion = "{message: \"Hello, world\", timestamp:2021-03-10T01:49:30.242-00:00}";
+        Message message = ION_MAPPER.readValue(ion, Message.class);
+        assertNotNull(message);
+        assertEquals("Hello, world", message.message);
+    }
+}