Bug 66425: Avoid exceptions found via poi-fuzz

Use correct default date-format, add some tests

Fixes https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=66381

git-svn-id: https://svn.apache.org/repos/asf/poi/trunk@1917070 13f79535-47bb-0310-9956-ffa450edef68

poi-ooxml/src/test/java/org/apache/poi/xssf/usermodel/TestXSSFDataFormat.java

 import static org.junit.jupiter.api.Assertions.assertEquals;
 
 import java.io.IOException;
+import java.util.Date;
 
 import org.apache.poi.ss.formula.ConditionalFormattingEvaluator;
 import org.apache.poi.ss.formula.WorkbookEvaluatorProvider;
             assertEquals("6.75", formatter.formatCellValue(d1));
         }
     }
+
+    @Test
+    public void testFormatCellValue() throws IOException {
+        DataFormatter df = new DataFormatter();
+
+        assertEquals("", df.formatCellValue(null));
+
+        try (Workbook wb = new XSSFWorkbook()) {
+            Cell cell = wb.createSheet("test").createRow(0).createCell(0);
+            assertEquals("", df.formatCellValue(cell));
+
+            cell.setCellValue(123);
+            assertEquals("123", df.formatCellValue(cell));
+
+            cell.setCellValue(new Date(234092383));
+            assertEquals("25571.75107", df.formatCellValue(cell));
+
+            cell.setCellValue("abcdefgh");
+            assertEquals("abcdefgh", df.formatCellValue(cell));
+
+            cell.setCellValue(true);
+            assertEquals("TRUE", df.formatCellValue(cell));
+
+            CellStyle cellStyle = wb.createCellStyle();
+            cellStyle.setDataFormat((short)14);
+            cell.setCellStyle(cellStyle);
+            cell.setCellValue(new Date(234092383));
+            assertEquals("1/3/70", df.formatCellValue(cell));
+
+            cellStyle.setDataFormat((short)9999);
+            assertEquals("25571.751069247686", df.formatCellValue(cell));
+        }
+    }
 }

poi/src/main/java/org/apache/poi/ss/usermodel/DataFormatter.java

                 sdf.setTimeZone(LocaleUtil.getUserTimeZone());
                 dateFormat = sdf;
             } else {
-                dateFormat = defaultNumFormat;
+                dateFormat = defaultDateformat;
             }
         }
         synchronized (dateFormat) {

poi/src/test/java/org/apache/poi/hssf/dev/TestBiffViewer.java

         excludes.put("clusterfuzz-testcase-minimized-POIHSSFFuzzer-5889658057523200.xls", IndexOutOfBoundsException.class);
         excludes.put("clusterfuzz-testcase-minimized-POIHSSFFuzzer-5175219985448960.xls", IndexOutOfBoundsException.class);
         excludes.put("clusterfuzz-testcase-minimized-POIHSSFFuzzer-6137883240824832.xls", IndexOutOfBoundsException.class);
+        excludes.put("clusterfuzz-testcase-minimized-POIHSSFFuzzer-6483562584932352.xls", IndexOutOfBoundsException.class);
 
         return excludes;
     }

poi/src/test/java/org/apache/poi/hssf/dev/TestRecordLister.java

         excludes.put("clusterfuzz-testcase-minimized-POIHSSFFuzzer-5889658057523200.xls", IndexOutOfBoundsException.class);
         excludes.put("clusterfuzz-testcase-minimized-POIHSSFFuzzer-5175219985448960.xls", RecordFormatException.class);
         excludes.put("clusterfuzz-testcase-minimized-POIHSSFFuzzer-6137883240824832.xls", RecordFormatException.class);
+        excludes.put("clusterfuzz-testcase-minimized-POIHSSFFuzzer-6483562584932352.xls", RecordFormatException.class);
 
         return excludes;
     }

poi/src/test/java/org/apache/poi/ss/usermodel/TestDataFormatter.java

 import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.TimeUnit;
 
+import javax.swing.text.DateFormatter;
+
 import org.apache.poi.POITestCase;
 import org.apache.poi.hssf.HSSFTestDataSamples;
 import org.apache.poi.hssf.usermodel.HSSFWorkbook;
         return true;
     }
 
+    @Test
+    public void testFormatCellValue() throws IOException {
+        DataFormatter df = new DataFormatter();
+
+        assertEquals("", df.formatCellValue(null));
+
+        try (Workbook wb = new HSSFWorkbook()) {
+            Cell cell = wb.createSheet("test").createRow(0).createCell(0);
+            assertEquals("", df.formatCellValue(cell));
+
+            cell.setCellValue(123);
+            assertEquals("123", df.formatCellValue(cell));
+
+            cell.setCellValue(new Date(234092383));
+            assertEquals("25571.75107", df.formatCellValue(cell));
+
+            cell.setCellValue("abcdefgh");
+            assertEquals("abcdefgh", df.formatCellValue(cell));
+
+            cell.setCellValue(true);
+            assertEquals("TRUE", df.formatCellValue(cell));
+
+            CellStyle cellStyle = wb.createCellStyle();
+            cellStyle.setDataFormat((short)14);
+            cell.setCellStyle(cellStyle);
+            cell.setCellValue(new Date(234092383));
+            assertEquals("1/3/70", df.formatCellValue(cell));
+
+            cellStyle.setDataFormat((short)9999);
+            assertEquals("25571.751069247686", df.formatCellValue(cell));
+        }
+    }
 }