Improve test coverage in CSVFormatTest (apache#65)

* Improve Format Coverage to 99percent

* code format add space

Author: dota17

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

@@ -41,6 +41,8 @@
 import java.io.StringReader;
 import java.lang.reflect.Method;
 import java.lang.reflect.Modifier;
+import java.sql.ResultSet;
+import java.sql.SQLException;
 import java.util.Arrays;
 
 import org.junit.jupiter.api.Test;
@@ -1205,4 +1207,75 @@ public void testFormatToString() throws IOException {
         assertEquals("Delimiter=<,> Escape=<?> QuoteChar=<\"> QuoteMode=<MINIMAL> NullString=<> RecordSeparator=<" +CRLF+
                 "> IgnoreHeaderCase:ignored SkipHeaderRecord:false HeaderComments:[This is HeaderComments] Header:[col1, col2, col3]", format.toString());
     }
+
+    @Test
+    public void testDelimiterSameAsRecordSeparatorThrowsException() {
+        assertThrows(IllegalArgumentException.class, () -> CSVFormat.newFormat(CR));
+    }
+
+    @Test
+    public void testWithHeaderEnumNull() {
+        final CSVFormat format =  CSVFormat.DEFAULT;
+        Class<Enum<?>> simpleName = null;
+        format.withHeader(simpleName);
+    }
+
+    @Test
+    public  void testWithHeaderResultSetNull() throws SQLException {
+        final CSVFormat format = CSVFormat.DEFAULT;
+        ResultSet resultSet = null;
+        format.withHeader(resultSet);
+    }
+
+    @Test
+    public void testPrintWithQuoteModeIsNONE() throws IOException {
+        final Reader in = new StringReader("a,b,c");
+        final Appendable out = new StringBuilder();
+        CSVFormat format = CSVFormat.RFC4180.withDelimiter(',').withQuote('"').withEscape('?').withQuoteMode(QuoteMode.NONE);
+        format.print(in, out, true);
+        assertEquals("a?,b?,c", out.toString());
+    }
+
+    @Test
+    public void testPrintWithQuotes() throws IOException {
+        final Reader in = new StringReader("\"a,b,c\r\nx,y,z");
+        final Appendable out = new StringBuilder();
+        CSVFormat format = CSVFormat.RFC4180.withDelimiter(',').withQuote('"').withEscape('?').withQuoteMode(QuoteMode.NON_NUMERIC);
+        format.print(in, out, true);
+        assertEquals("\"\"\"\"a,b,c\r\nx,y,z\"", out.toString());
+    }
+
+    @Test
+    public void testPrintWithoutQuotes() throws IOException {
+        final Reader in = new StringReader("");
+        final Appendable out = new StringBuilder();
+        CSVFormat format = CSVFormat.RFC4180.withDelimiter(',').withQuote('"').withEscape('?').withQuoteMode(QuoteMode.NON_NUMERIC);
+        format.print(in, out, true);
+        assertEquals("\"\"", out.toString());
+    }
+
+    @Test
+    public void testTrim() throws IOException {
+        CSVFormat formatWithTrim = CSVFormat.DEFAULT.withDelimiter(',').withTrim().withQuote(null).withRecordSeparator(CRLF);
+
+        CharSequence in = "a,b,c";
+        final StringBuilder out = new StringBuilder();
+        formatWithTrim.print(in, out, true);
+        assertEquals("a,b,c", out.toString());
+
+        in = new StringBuilder(" x,y,z");
+        out.setLength(0);
+        formatWithTrim.print(in, out, true);
+        assertEquals("x,y,z", out.toString());
+
+        in = new StringBuilder("");
+        out.setLength(0);
+        formatWithTrim.print(in, out, true);
+        assertEquals("", out.toString());
+
+        in = new StringBuilder("header\r\n");
+        out.setLength(0);
+        formatWithTrim.print(in, out, true);
+        assertEquals("header", out.toString());
+    }
 }