Function skip_string_backward

src/completion/named_args.rs:202–224

Skip backward past a string literal ending at position `end` (which points to the closing quote character `q`). Returns the position of the opening quote, or 0 if not found.

(chars: &[char], end: usize, q: char)

///
/// Returns the position of the opening quote, or 0 if not found.
pub fn skip_string_backward(chars: &[char], end: usize, q: char) -> usize {
    if end == 0 {
        return 0;
    }
    let mut j = end - 1;
    while j > 0 {
        if chars[j] == q {
            // Check it's not escaped
            let mut backslashes = 0u32;
            let mut k = j;
            while k > 0 && chars[k - 1] == '\\' {
                backslashes += 1;
                k -= 1;
            }
            if backslashes.is_multiple_of(2) {
                // Not escaped — this is the opening quote
                return j;
            }
        }
        j -= 1;
    }
    0
}

/// Extract the call expression that precedes the opening paren at `open`.
///