Fix typo in date format (#26503)

core/src/main/java/org/elasticsearch/common/joda/Joda.java

@@ -79,7 +79,7 @@ public static FormatDateTimeFormatter forPattern(String input, Locale locale) {
             formatter = ISODateTimeFormat.basicTime();
         } else if ("basicTimeNoMillis".equals(input) || "basic_time_no_millis".equals(input)) {
             formatter = ISODateTimeFormat.basicTimeNoMillis();
-        } else if ("basicTTime".equals(input) || "basic_t_Time".equals(input)) {
+        } else if ("basicTTime".equals(input) || "basic_t_time".equals(input)) {
             formatter = ISODateTimeFormat.basicTTime();
         } else if ("basicTTimeNoMillis".equals(input) || "basic_t_time_no_millis".equals(input)) {
             formatter = ISODateTimeFormat.basicTTimeNoMillis();

core/src/test/java/org/elasticsearch/common/joda/JodaTests.java

@@ -0,0 +1,53 @@
+/*
+ * Licensed to Elasticsearch under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch licenses this file to you under
+ * the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+package org.elasticsearch.common.joda;
+
+import org.elasticsearch.test.ESTestCase;
+import org.joda.time.DateTime;
+import org.joda.time.DateTimeZone;
+import org.joda.time.format.DateTimeFormatter;
+
+
+public class JodaTests extends ESTestCase {
+
+
+    public void testBasicTTimePattern() {
+        FormatDateTimeFormatter formatter1 = Joda.forPattern("basic_t_time");
+        assertEquals(formatter1.format(), "basic_t_time");
+        DateTimeFormatter parser1 = formatter1.parser();
+
+        assertEquals(parser1.getZone(), DateTimeZone.UTC);
+
+        FormatDateTimeFormatter formatter2 = Joda.forPattern("basicTTime");
+        assertEquals(formatter2.format(), "basicTTime");
+        DateTimeFormatter parser2 = formatter2.parser();
+
+        assertEquals(parser2.getZone(), DateTimeZone.UTC);
+
+        DateTime dt = new DateTime(2004, 6, 9, 10, 20, 30, 40, DateTimeZone.UTC);
+        assertEquals("T102030.040Z", parser1.print(dt));
+        assertEquals("T102030.040Z", parser2.print(dt));
+
+        expectThrows(IllegalArgumentException.class, () -> Joda.forPattern("basic_t_Time"));
+        expectThrows(IllegalArgumentException.class, () -> Joda.forPattern("basic_T_Time"));
+        expectThrows(IllegalArgumentException.class, () -> Joda.forPattern("basic_T_time"));
+    }
+
+}