#RK3 Negative Character Groups: Wrong test case?

Challenges
1

One of the test cases for this stage is:

echo -n "orange" | ./your_program.sh -E "[^opq]"

Challenge description says: “Negative character groups match any character that is not present within a pair of square brackets.”

Since ‘o’ is in “orange”, my code returns exit code 1 but the test expects 0.

[tester::#RK3] Running tests for Stage #RK3 (Negative Character Groups)
[tester::#RK3] $ echo -n "apple" | ./your_program.sh -E "[^xyz]"
[your_program] negative character group search: xyz
[tester::#RK3] ✓ Received exit code 0.
[tester::#RK3] $ echo -n "banana" | ./your_program.sh -E "[^anb]"
[your_program] negative character group search: anb
[tester::#RK3] ✓ Received exit code 1.
[tester::#RK3] $ echo -n "orange" | ./your_program.sh -E "[^opq]"
[your_program] negative character group search: opq
[tester::#RK3] expected exit code 0, got 1
[tester::#RK3] Test failed (try setting 'debug: true' in your codecrafters.yml to see more details)

Here’s my code:

func matchLine(line []byte, pattern string) (bool, error) {
	if utf8.RuneCountInString(pattern) == 0 {
		return false, fmt.Errorf("unsupported pattern: %q", pattern)
	}

	// alphanumeric
	search := strings.ReplaceAll(pattern, "\\w", "\\dabcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ_")
	// numeric
	search = strings.ReplaceAll(search, "\\d", "0123456789")
	// positive group
	if strings.HasPrefix(search, "[") && strings.HasSuffix(search, "]") {
		search = strings.Replace(search, "[", "", 1)
		search = strings.Replace(search, "]", "", 1)
		// negative group
		if strings.HasPrefix(search, "^") {
			search = strings.Replace(search, "^", "", 1)
			fmt.Printf("negative character group search: %s\n", search)
			return !bytes.ContainsAny(line, search), nil
		}
	}

	return bytes.ContainsAny(line, search), nil
}

I checked other solutions and they’re doing what I’m doing. Is the test case wrong or I’m doing something wrong here?

4

Hey @0xi4o, this is a newly added test case, so some previously passing solutions might now fail.

To clarify: [^opq] will not match o, but it will match range. You can test this behavior using grep directly:

image
image778×112 13.7 KB

Let me know if you’d like further clarification!

1 Like
6

Ah ok. I got it.

Thanks. I was able to solve the stage.

1 Like