Code editor toggle comment doesn't uncomment if there's a different amount of #'s

[aXu-AP]

Godot version

v4.2.beta1.official [b137180]

System information

Windows 10

Issue description

Toggle comment adds more comment delimiters when there's different amount of delimiters, even if all the lines are commented.

Current behavior:

Expected behavior (from v4.2.dev6.official [57a6813]):

Regression likely happened in #81486

Steps to reproduce

Open script editor. Comment some lines. Then select bigger area enclosing some of the commented lines, and toggle comment twice or more.

Minimal reproduction project

N/A

[aXu-AP]

I might fix this next week if I have time, but feel free to work on this if you want. Shouldn't be hard to fix.

[Lunarisnia]

I would love to try and fix this, can I get assigned to this issue?

[aXu-AP]

Just go ahead, issues aren't usually assigned 👍

[Lunarisnia]

godot/editor/code_editor.cpp

Line 1504 in a574c02

int delimiter_idx = text_editor->is_in_comment(line, text_editor->get_first_non_whitespace_column(line) + delimiter.length());

godot/scene/gui/code_edit.cpp

Lines 1912 to 1915 in a574c02

	String CodeEdit::get_delimiter_start_key(int p_delimiter_idx) const {
	ERR_FAIL_INDEX_V(p_delimiter_idx, delimiters.size(), "");
	return delimiters[p_delimiter_idx].start_key;
	}

godot/scene/gui/code_edit.cpp

Lines 2939 to 2963 in a574c02

	for (int d = 0; d < delimiters.size(); d++) {
	/* check there is enough room */
	int chars_left = line_length - from;
	int start_key_length = delimiters[d].start_key.length();
	int end_key_length = delimiters[d].end_key.length();
	if (chars_left < start_key_length) {
	continue;
	}
	/* search the line */
	bool match = true;
	const char32_t *start_key = delimiters[d].start_key.get_data();
	for (int k = 0; k < start_key_length; k++) {
	if (start_key[k] != str[from + k]) {
	match = false;
	break;
	}
	}
	if (!match) {
	continue;
	}
	same_line = true;
	in_region = d;
	delimiter_cache.write[i][from + 1] = d;
	from += start_key_length;

From my investigation. The issue seems to root from the function CodeEdit::is_in_comment returning 2 instead of 3 when there is a multiple comment delimiter in a line. it seems to cause CodeEdit::get_delimiter_start_key to return ## instead of # which cause the error. CMIIW

This issue can also be reproduced by simply adding multiple comment delimiter in a line then using the In-line comment shortcut:
Example:

# Try using the inline comment shortcut on this line below
##var l1

[aXu-AP]

Thanks @Lunarisnia for taking care of this!