CSVReaderTest.java

package no.priv.garshol.duke.utils;

import java.io.IOException;
import java.io.InputStream;
import java.io.StringReader;
import java.io.InputStreamReader;

import org.junit.Test;
import static org.junit.Assert.fail;
import static org.junit.Assert.assertTrue;

import no.priv.garshol.duke.DukeException;

public class CSVReaderTest {

  @Test
  public void testEmpty() throws IOException {
    String data = "";
    CSVReader reader = new CSVReader(new StringReader(data));
    compareRows("couldn't read empty file correctly", null, reader.next());
  }

  @Test
  public void testOneRow() throws IOException {
    String data = "a,b,c";
    CSVReader reader = new CSVReader(new StringReader(data));

    String[] row = reader.next();
    compareRows("first row read incorrectly", new String[]{"a", "b", "c"},
                row);
    compareRows("reading not terminated correctly", null, reader.next());
  }

  @Test
  public void testOneRowWithLineBreak() throws IOException {
    String data = "a,b,c\n";
    CSVReader reader = new CSVReader(new StringReader(data));

    String[] row = reader.next();
    compareRows("first row read incorrectly", new String[]{"a", "b", "c"},
                row);
    compareRows("reading not terminated correctly", null, reader.next());
  }

  @Test
  public void testTwoRows() throws IOException {
    String data = "a,b,c\nd,e,f";
    CSVReader reader = new CSVReader(new StringReader(data));

    String[] row = reader.next();
    compareRows("first row read incorrectly", new String[]{"a", "b", "c"},
                row);
    row = reader.next();
    compareRows("second row read incorrectly", new String[]{"d", "e", "f"},
                row);
    compareRows("reading not terminated correctly", null, reader.next());
  }

  @Test
  public void testOneRowQuotes() throws IOException {
    String data = "\"a\",\"b\",\"c\"";
    CSVReader reader = new CSVReader(new StringReader(data));

    String[] row = reader.next();
    compareRows("first row read incorrectly", new String[]{"a", "b", "c"},
                row);
    compareRows("reading not terminated correctly", null, reader.next());
  }

  @Test
  public void testOneRowInconsistentQuotes() throws IOException {
    String data = "\"a\",b,\"c\"";
    CSVReader reader = new CSVReader(new StringReader(data));

    String[] row = reader.next();
    compareRows("first row read incorrectly", new String[]{"a", "b", "c"},
                row);
    compareRows("reading not terminated correctly", null, reader.next());
  }

  @Test
  public void testTwoRowsQuotes() throws IOException {
    String data = "\"a\",\"b\",\"c\"\n\"d\",\"e\",\"f\"";
    CSVReader reader = new CSVReader(new StringReader(data));

    String[] row = reader.next();
    compareRows("first row read incorrectly", new String[]{"a", "b", "c"},
                row);
    row = reader.next();
    compareRows("second row read incorrectly", new String[]{"d", "e", "f"},
                row);
    compareRows("reading not terminated correctly", null, reader.next());
  }

  @Test
  public void testOneRowQuotesLineBreak() throws IOException {
    String data = "\"a\",\"b\nc\",\"d\"";
    CSVReader reader = new CSVReader(new StringReader(data));

    String[] row = reader.next();
    compareRows("first row read incorrectly", new String[]{"a", "b\nc", "d"},
                row);
    compareRows("reading not terminated correctly", null, reader.next());
  }

  @Test
  public void testTwoRowsRN() throws IOException {
    String data = "a,b,c\r\nd,e,f";
    CSVReader reader = new CSVReader(new StringReader(data));

    String[] row = reader.next();
    compareRows("first row read incorrectly", new String[]{"a", "b", "c"},
                row);
    row = reader.next();
    compareRows("second row read incorrectly", new String[]{"d", "e", "f"},
                row);
    compareRows("reading not terminated correctly", null, reader.next());
  }

  @Test
  public void testTwoRowsR() throws IOException {
    String data = "a,b,c\rd,e,f";
    CSVReader reader = new CSVReader(new StringReader(data));

    String[] row = reader.next();
    compareRows("first row read incorrectly", new String[]{"a", "b", "c"},
                row);
    row = reader.next();
    compareRows("second row read incorrectly", new String[]{"d", "e", "f"},
                row);
    compareRows("reading not terminated correctly", null, reader.next());
  }

  @Test
  public void testTwoRowsBuffering() throws IOException {
    String data = "aaa,bbb,ccc\nddd,eee,fff";
    CSVReader reader = new CSVReader(new StringReader(data), 15, null);

    String[] row = reader.next();
    compareRows("first row read incorrectly", new String[]{"aaa", "bbb", "ccc"},
                row);
    row = reader.next();
    compareRows("second row read incorrectly", new String[]{"ddd", "eee", "fff"},
                row);
    compareRows("reading not terminated correctly", null, reader.next());
  }

  @Test
  public void testOneRowQuotesAndComma() throws IOException {
    String data = "aaa,\"b,b\",ccc";
    CSVReader reader = new CSVReader(new StringReader(data));

    String[] row = reader.next();
    compareRows("first row read incorrectly", new String[]{"aaa", "b,b", "ccc"},
                row);
    compareRows("reading not terminated correctly", null, reader.next());
  }

  @Test
  public void testOneRowEmptyQuoted() throws IOException {
    String data = "aaa,\"\",ccc";
    CSVReader reader = new CSVReader(new StringReader(data));

    String[] row = reader.next();
    compareRows("first row read incorrectly", new String[]{"aaa", "", "ccc"},
                row);
    compareRows("reading not terminated correctly", null, reader.next());
  }

  @Test
  public void testOneRowWithQuoteCharacters() throws IOException {
    String data = "TRMMMXN128F42936A5,\"Symphony No. 1 G minor \"\"Sinfonie Serieuse\"\"/Allegro con energia\",SOZVAPQ12A8C13B63C,\"Berwald: Symphonies Nos. 1/2/3/4\",AR2NS5Y1187FB5879D";
    CSVReader reader = new CSVReader(new StringReader(data));

    String[] row = reader.next();
    compareRows("first row read incorrectly",
                new String[]{"TRMMMXN128F42936A5",
                             "Symphony No. 1 G minor \"Sinfonie Serieuse\"/Allegro con energia",
                             "SOZVAPQ12A8C13B63C",
                             "Berwald: Symphonies Nos. 1/2/3/4",
                             "AR2NS5Y1187FB5879D"},
                row);
    compareRows("reading not terminated correctly", null, reader.next());
  }

  @Test
  public void testOneRowWithQuoteCharacters2() throws IOException {
    String data = "\"\"\"quoted\"\"\"";
    CSVReader reader = new CSVReader(new StringReader(data));

    String[] row = reader.next();
    compareRows("first row read incorrectly",
                new String[]{"\"quoted\""},
                row);
    compareRows("reading not terminated correctly", null, reader.next());
  }

  @Test
  public void testSeparator() throws IOException {
    String data = "a;b;c\nd;e;f";
    CSVReader reader = new CSVReader(new StringReader(data));
    reader.setSeparator(';');

    String[] row = reader.next();
    compareRows("first row read incorrectly", new String[]{"a", "b", "c"},
                row);
    row = reader.next();
    compareRows("second row read incorrectly", new String[]{"d", "e", "f"},
                row);
    compareRows("reading not terminated correctly", null, reader.next());
  }

  @Test
  public void testBigBadFile2() throws IOException {
    // the problem with this file is that it contains unbalanced quotes,
    // but now we've set the buffer size bigger than the file size. that
    // should lead to a different error message

    ClassLoader cloader = Thread.currentThread().getContextClassLoader();
    InputStream istream = cloader.getResourceAsStream("big-bad.csv");
    CSVReader reader = new CSVReader(new InputStreamReader(istream),
                                     90000, "big-bad.csv");

    try {
      String[] row = reader.next();
      while (reader.next() != null)
        ;
      fail("Shouldn't accept malformed file");
    } catch (DukeException e) {
      // error message must contain name of file
      assertTrue(e.getMessage().indexOf("big-bad.csv") != -1);
    }
  }

  @Test
  public void testBigBadFile() throws IOException {
    // the problem with this file is that it contains unbalanced quotes,
    // leading to a row that's longer than the buffer. that used to cause
    // a stack overflow crash. we verify that instead we get an error message

    ClassLoader cloader = Thread.currentThread().getContextClassLoader();
    InputStream istream = cloader.getResourceAsStream("big-bad.csv");
    CSVReader reader = new CSVReader(new InputStreamReader(istream),
                                     65536, "big-bad.csv");

    try {
      String[] row = reader.next();
      while (reader.next() != null)
        ;
      fail("Shouldn't accept malformed file");
    } catch (DukeException e) {
      // error message must contain name of file
      assertTrue(e.getMessage().indexOf("big-bad.csv") != -1);
    }
  }

  @Test
  public void testOneRowQuotesAndNewline() throws IOException {
    String data = "aaa,\"b,b\",\"ccc\"\n";
    CSVReader reader = new CSVReader(new StringReader(data));

    String[] row = reader.next();
    compareRows("first row read incorrectly", new String[]{"aaa", "b,b", "ccc"},
                row);
    compareRows("reading not terminated correctly", null, reader.next());
  }

  // ===== UTILITIES

  private void compareRows(String msg, String[] row1, String[] row2) {
    if (row1 == row2)
      return;

    if (row1 == null && row2 != null)
      fail(msg + " expected null, but received " + toString(row2));
    if (row1 != null && row2 == null)
      fail(msg + " expected " + toString(row1) + ", but received null");

    boolean equals = row1.length == row2.length;
    for (int ix = 0; equals && ix < row1.length; ix++)
      if (!row1[ix].equals(row2[ix]))
        equals = false;

    if (!equals)
      fail(msg + " expected " + toString(row1) +
           ", but received " + toString(row2));
  }

  public static String toString(String[] row) {
    if (row == null)
      return "null";

    StringBuffer buf = new StringBuffer();
    buf.append("[");
    for (int ix = 0; ix < row.length; ix++) {
      buf.append("\"" + row[ix] + "\"");
      if (ix + 1 < row.length)
        buf.append(", ");
    }
    buf.append("]");
    return buf.toString();
  }
}