    @Test public void testReadLine() {

        BufferedReader br = getBufferedReader();
        char currentChar;
        char[] line = new char[8192];
        int index = -1;
        br.mark(8192);
        while ((currentChar = (char) br.read()) != '\n') {
            line[++index] = currentChar;
        }

        // drop the unused characters in line buffer
        char[] trimedLine = new char[index];
        for (int i = 0; i < index; i++) {
            trimedLine[i] = line[i];
        }

        String stringLine = new String(trimedLine);
        br.reset();
        String sut = br.readLine();

        assertEquals(sut, stringLine);

        br.close();
    }