Fix bug where parsing the rare occurence of leap-second without time…

…-offset (#23)

* Added error checking and throwing DateTimeParseException to include the parse position where the error occurred
* Add fuzzer tests
* Fix bug where parsing the rare occurence of leap-second without time-offset in date-time would fail

---------

Co-authored-by: Morten Haraldsen <dev@ethlo.com>

pom.xml

@@ -60,6 +60,12 @@ limitations under the License.
             <version>5.10.1</version>
             <scope>test</scope>
         </dependency>
+        <dependency>
+            <groupId>com.code-intelligence</groupId>
+            <artifactId>jazzer-junit</artifactId>
+            <version>0.22.1</version>
+            <scope>test</scope>
+        </dependency>
     </dependencies>
     <build>
         <plugins>

src/main/java/com/ethlo/time/internal/EthloITU.java

@@ -308,7 +308,6 @@ private static Object handleTime(int year, int month, int day, int hour, int min
         if (remaining == 2)
         {
             final int seconds = parsePositiveInt(chars, 17, 19);
-            leapSecondCheck(year, month, day, hour, minute, 0, 0, null);
             if (raw)
             {
                 return new DateTime(Field.SECOND, year, month, day, hour, minute, seconds, 0, null, 0);
@@ -389,10 +388,10 @@ else if (c == PLUS || c == MINUS)
         }
 
         final int second = parsePositiveInt(chars, 17, 19);
-        leapSecondCheck(year, month, day, hour, minute, second, fractions, offset);
 
         if (!raw)
         {
+            leapSecondCheck(year, month, day, hour, minute, second, fractions, offset);
             return OffsetDateTime.of(year, month, day, hour, minute, second, fractions, offset.toZoneOffset());
         }
         return fractionDigits > 0 ? DateTime.of(year, month, day, hour, minute, second, fractions, offset, fractionDigits) : DateTime.of(year, month, day, hour, minute, second, offset);
@@ -415,8 +414,8 @@ private static void leapSecondCheck(int year, int month, int day, int hour, int
             final boolean isValidLeapYearMonth = leapSecondHandler.isValidLeapSecondDate(needle);
             if (isValidLeapYearMonth || needle.isAfter(leapSecondHandler.getLastKnownLeapSecond()))
             {
-                final int utcHour = hour - (offset.getTotalSeconds() / 3_600);
-                final int utcMinute = minute - ((offset.getTotalSeconds() % 3_600) / 60);
+                final int utcHour = hour - offset.getTotalSeconds() / 3_600;
+                final int utcMinute = minute - (offset.getTotalSeconds() % 3_600) / 60;
                 if (((month == Month.DECEMBER.getValue() && day == 31) || (month == Month.JUNE.getValue() && day == 30))
                         && utcHour == 23
                         && utcMinute == 59)

src/test/java/com/ethlo/time/CorrectnessTest.java

@@ -470,4 +470,10 @@ void testTemporalAccessorNanos()
 
         assertThat(parsed.getLong(ChronoField.NANO_OF_SECOND)).isEqualTo(987654321);
     }
+
+    @Test
+    void testParseLeapSecondWhenNoTimeOffsetPresent()
+    {
+        ITU.parseLenient("3011-10-02T22:00:60.003");
+    }
 }

src/test/java/com/ethlo/time/fuzzer/ParseDateTimeFuzzTest.java

@@ -0,0 +1,42 @@
+package com.ethlo.time.fuzzer;
+
+/*-
+ * #%L
+ * Internet Time Utility
+ * %%
+ * Copyright (C) 2017 - 2024 Morten Haraldsen (ethlo)
+ * %%
+ * Licensed 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.
+ * #L%
+ */
+
+import java.time.DateTimeException;
+
+import com.code_intelligence.jazzer.api.FuzzedDataProvider;
+import com.ethlo.time.ITU;
+
+public class ParseDateTimeFuzzTest
+{
+    @com.code_intelligence.jazzer.junit.FuzzTest(maxDuration = "2m")
+    void parse(FuzzedDataProvider data)
+    {
+        try
+        {
+            ITU.parseDateTime(data.consumeRemainingAsAsciiString());
+        }
+        catch (DateTimeException ignored)
+        {
+
+        }
+    }
+}

src/test/java/com/ethlo/time/fuzzer/ParseLenientFuzzTest.java

@@ -0,0 +1,51 @@
+package com.ethlo.time.fuzzer;
+
+/*-
+ * #%L
+ * Internet Time Utility
+ * %%
+ * Copyright (C) 2017 - 2024 Morten Haraldsen (ethlo)
+ * %%
+ * Licensed 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.
+ * #L%
+ */
+
+import java.time.DateTimeException;
+
+import com.code_intelligence.jazzer.api.FuzzedDataProvider;
+import com.ethlo.time.DateTime;
+import com.ethlo.time.ITU;
+
+public class ParseLenientFuzzTest
+{
+    @com.code_intelligence.jazzer.junit.FuzzTest(maxDuration = "2m")
+    void parse(FuzzedDataProvider data)
+    {
+        DateTime d = null;
+        try
+        {
+            d = ITU.parseLenient(data.consumeRemainingAsString());
+        }
+        catch (DateTimeException ignored)
+        {
+
+        }
+
+        if (d != null)
+        {
+            d.toInstant();
+            System.out.println(d);
+            d.toString();
+        }
+    }
+}