Increase test coverage

Author: sigee

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

@@ -304,7 +304,7 @@ private void put(final String name, final Integer index) {
         }
 
         public boolean isEmpty() {
-            return this.headerMap == null || this.headerMap.isEmpty();
+            return this.headerMap.isEmpty();
         }
     }
 
@@ -619,7 +619,7 @@ private Headers createHeaders() throws IOException {
         final Headers headers = new Headers(format);
         final String[] formatHeader = format.getHeader();
         if (formatHeader != null) {
-            final String[] headerRecord = getHeaderRecord();
+            final String[] headerRecord = getHeaderRecord(formatHeader);
             // build the name to index mappings
             if (headerRecord != null) {
                 // Track an occurrence of a null, empty or blank header.
@@ -657,26 +657,23 @@ private Headers createHeaders() throws IOException {
      *         If the format does not contain header record, the header record from the first line of the file
      * @throws IOException if there is a problem reading the header or skipping the first record
      */
-    private String[] getHeaderRecord() throws IOException {
+    private String[] getHeaderRecord(final String[] formatHeader) throws IOException {
         String[] headerRecord = null;
-        final String[] formatHeader = format.getHeader();
-        if (formatHeader != null) {
-            if (formatHeader.length == 0) {
-                // read the header from the first line of the file
+        if (formatHeader.length == 0) {
+            // read the header from the first line of the file
+            final CSVRecord nextRecord = nextRecord();
+            if (nextRecord != null) {
+                headerRecord = nextRecord.values();
+                headerComment = nextRecord.getComment();
+            }
+        } else {
+            if (format.getSkipHeaderRecord()) {
                 final CSVRecord nextRecord = nextRecord();
                 if (nextRecord != null) {
-                    headerRecord = nextRecord.values();
                     headerComment = nextRecord.getComment();
                 }
-            } else {
-                if (format.getSkipHeaderRecord()) {
-                    final CSVRecord nextRecord = nextRecord();
-                    if (nextRecord != null) {
-                        headerComment = nextRecord.getComment();
-                    }
-                }
-                headerRecord = formatHeader;
             }
+            headerRecord = formatHeader;
         }
         return headerRecord;
     }

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

@@ -729,6 +729,30 @@ void testGetHeaderMap() throws Exception {
         }
     }
 
+    @Test
+    void testGetHeaderMapWithIgnoreHeaderCase() throws Exception {
+        try (CSVParser parser = CSVParser.parse("a,b,c,A,B,C\n1,2,3,1,2,3\nx,y,z,x,y,z", CSVFormat.DEFAULT.withHeader("a", "b", "c").withIgnoreHeaderCase())) {
+            final Map<String, Integer> headerMap = parser.getHeaderMap();
+            final Iterator<String> columnNames = headerMap.keySet().iterator();
+            // Headers are iterated in column order.
+            assertEquals("a", columnNames.next());
+            assertEquals("b", columnNames.next());
+            assertEquals("c", columnNames.next());
+            final Iterator<CSVRecord> records = parser.iterator();
+
+            // Parse to make sure getHeaderMap did not have a side-effect.
+            for (int i = 0; i < 3; i++) {
+                assertTrue(records.hasNext());
+                final CSVRecord record = records.next();
+                assertEquals(record.get(0), record.get("a"));
+                assertEquals(record.get(1), record.get("b"));
+                assertEquals(record.get(2), record.get("c"));
+            }
+
+            assertFalse(records.hasNext());
+        }
+    }
+
     @Test
     void testGetHeaderNames() throws IOException {
         try (CSVParser parser = CSVParser.parse("a,b,c\n1,2,3\nx,y,z", CSVFormat.DEFAULT.withHeader("A", "B", "C"))) {