private static final class Snippet {
        final int line;       // line of the [.multi-language-sample] header
        final Language lang;  // best-effort deduction (UNKNOWN allowed)

        Snippet(int line, Language lang) {
            this.line = line;
            this.lang = lang;
        }
    }

    private static final class Error {
        final int line;
        final String message;

    TestCharSource lines = new TestCharSource(LINES);
    assertThat(lines.readFirstLine()).isEqualTo("foo");
    assertTrue(lines.wasStreamOpened() && lines.wasStreamClosed());
  }

  public void testReadLines_toList() throws IOException {
    TestCharSource lines = new TestCharSource(LINES);
    assertEquals(ImmutableList.of("foo", "bar", "baz", "something"), lines.readLines());

    public static List<String> format(String... lines) {
        int size = DEFAULT_MAX_SIZE;
        int remainder = size - 4; // 4 chars = 2 box_char + 2 spaces
        List<String> result = new ArrayList<>();
        StringBuilder sb = new StringBuilder(size);
        // first line
        sb.setLength(0);
        repeat(sb, BOX_CHAR, size);
        result.add(sb.toString());
        // lines
        for (String line : lines) {

        try (Stream<String> stream = Files.lines(configFile, StandardCharsets.UTF_8)) {
            Iterator<String> lines = stream.iterator();
            boolean foundOrigin = false;
            while (lines.hasNext()) {
                String line = lines.next().trim();
                if (line.startsWith(";") || line.startsWith("#")) {
                    // ignore comments

	}
	return bytes.TrimSpace(out), nil
}

func getLines(cmd *exec.Cmd) [][]byte {
	out := output(cmd)
	lines := bytes.Split(out, []byte("\n"))
	// Skip the empty line at the end.
	if len(lines[len(lines)-1]) == 0 {
		lines = lines[:len(lines)-1]
	}
	return lines
}

func output(cmd *exec.Cmd) []byte {
	out, err := cmd.Output()
	if err != nil {
		fmt.Println(strings.Join(cmd.Args, "\n"))

            // Verify content structure
            boolean hasThreadLine = lines.stream().anyMatch(line -> line.startsWith("Thread:"));
            boolean hasStackTraceLine = lines.stream().anyMatch(line -> line.startsWith("\tat "));

            assertTrue("Should contain thread information", hasThreadLine);
            assertTrue("Should contain stack trace information", hasStackTraceLine);

        List<String> lines = new ArrayList<>();
        for (String line = readLine(); line != null && !line.isEmpty(); line = readLine()) {
            lines.add(line);
        }
        return lines;
    }

    @Override
    public void write(String line) throws IOException {
        try {
            prompter.showMessage(line);

	seq := 0
	hexByLine := map[string]string{}
	lines := strings.SplitAfter(string(data), "\n")
Diff:
	for _, line := range lines {
		lineno++

		// Ignore include of textflag.h.
		if strings.HasPrefix(line, "#include ") {
			continue
		}

		// Ignore GLOBL.
		if strings.HasPrefix(line, "GLOBL ") {
			continue
		}

		// The general form of a test input line is:
		//	// comment

                // go back and fetch the reproduction line for this test failure
                Deque<String> lines = reproductionLines.get(Descriptor.of(testDescriptor.getParent()));
                if (lines != null) {
                    String line = lines.getLast();
                    if (line != null) {
                        System.err.print('\n' + line);
                    }
                }

        val lines = content.substring(startAfterIntro).lines()
        var pos = startAfterIntro
        var pastBlankLine = false
        for (line in lines) {
            if (pastBlankLine && !line.startsWith("- ") && line.isNotBlank()) {
                return pos
            }
            if (line.isNotBlank()) {
                pastBlankLine = true
            }