CSVParser.parse(String, CSVFormat) with a null CSVFormat maps to

CSVFormat.DEFAULT (like CSVParser.parse(Reader, CSVFormat))

Author: garydgregory

src/changes/changes.xml

@@ -44,7 +44,8 @@
       <!-- FIX -->
       <action type="fix" issue="CSV-317" dev="ggregory" due-to="Filipe Roque">Release history link changed from changes-report.html to changes.html #516.</action>
       <action type="fix" dev="ggregory" due-to="Gary Gregory">Remove -nouses directive from maven-bundle-plugin. OSGi package imports now state 'uses' definitions for package imports, this doesn't affect JPMS (from org.apache.commons:commons-parent:80).</action>
-      <action type="fix" issue="CSV-317" dev="ggregory" due-to="Gary Gregory">CSVParser.parse(URL, Charset, CSVFormat) with a null CSVFormat maps to CSVFormat.DEFAULT (like CSVParser.parse(Reader, CSVFormat)).</action>
+      <action type="fix" dev="ggregory" due-to="Gary Gregory">CSVParser.parse(URL, Charset, CSVFormat) with a null CSVFormat maps to CSVFormat.DEFAULT (like CSVParser.parse(Reader, CSVFormat)).</action>
+      <action type="fix" dev="ggregory" due-to="Gary Gregory">CSVParser.parse(String, CSVFormat) with a null CSVFormat maps to CSVFormat.DEFAULT (like CSVParser.parse(Reader, CSVFormat)).</action>
       <!-- ADD -->
       <action type="add" dev="ggregory" due-to="Gary Gregory">Define and use Maven property commons.jmh.version.</action> 
       <action type="add" dev="ggregory" due-to="Gary Gregory">Add CSVFormat.Builder.setMaxRows(long).</action> 

src/main/java/org/apache/commons/csv/CSVParser.java

@@ -403,7 +403,7 @@ public static CSVParser parse(final Reader reader, final CSVFormat format) throw
      * @param string
      *            a CSV string. Must not be null.
      * @param format
-     *            the CSVFormat used for CSV parsing. Must not be null.
+     *            the CSVFormat used for CSV parsing, {@code null} maps to {@link CSVFormat#DEFAULT}.
      * @return a new parser
      * @throws IllegalArgumentException
      *             If the parameters of the format are inconsistent or if either string or format are null.
@@ -413,7 +413,6 @@ public static CSVParser parse(final Reader reader, final CSVFormat format) throw
      */
     public static CSVParser parse(final String string, final CSVFormat format) throws IOException {
         Objects.requireNonNull(string, "string");
-        Objects.requireNonNull(format, "format");
         return parse(new StringReader(string), format);
     }
 

src/test/java/org/apache/commons/csv/CSVParserTest.java

@@ -1454,8 +1454,17 @@ public void testParserUrlNullCharsetFormat() {
     }
 
     @Test
-    public void testParseStringNullFormat() {
-        assertThrows(NullPointerException.class, () -> CSVParser.parse("csv data", (CSVFormat) null));
+    public void testParseStringNullFormat() throws IOException {
+        try (CSVParser parser = CSVParser.parse("1,2,3", null)) {
+            // null maps to DEFAULT.
+            final List<CSVRecord> records = parser.getRecords();
+            assertEquals(1, records.size());
+            final CSVRecord record = records.get(0);
+            assertEquals(3, record.size());
+            assertEquals("1", record.get(0));
+            assertEquals("2", record.get(1));
+            assertEquals("3", record.get(2));
+        }
     }
 
     @Test