Function extract_argument_text

src/inlay_hints.rs:442–492

Extract the argument text up to the next top-level comma or closing paren, respecting nesting of `()`, `[]`, and `{}`.

(s: &str)

/// Extract the argument text up to the next top-level comma or closing
/// paren, respecting nesting of `()`, `[]`, and `{}`.
fn extract_argument_text(s: &str) -> &str {
    let mut depth_paren = 0i32;
    let mut depth_bracket = 0i32;
    let mut depth_brace = 0i32;
    let mut in_single_quote = false;
    let mut in_double_quote = false;
    let mut prev_was_escape = false;

    for (i, ch) in s.char_indices() {
        if prev_was_escape {
            prev_was_escape = false;
            continue;
        }
        if ch == '\\' && (in_single_quote || in_double_quote) {
            prev_was_escape = true;
            continue;
        }
        if in_single_quote {
            if ch == '\'' {
                in_single_quote = false;
            }
            continue;
        }
        if in_double_quote {
            if ch == '"' {
                in_double_quote = false;
            }
            continue;
        }
        match ch {
            '\'' => in_single_quote = true,
            '"' => in_double_quote = true,
            '(' => depth_paren += 1,
            ')' => {
                if depth_paren == 0 {
                    return &s[..i];
                }
                depth_paren -= 1;
            }
            '[' => depth_bracket += 1,
            ']' => depth_bracket = (depth_bracket - 1).max(0),
            '{' => depth_brace += 1,
            '}' => depth_brace = (depth_brace - 1).max(0),
            ',' if depth_paren == 0 && depth_bracket == 0 && depth_brace == 0 => {
                return &s[..i];
            }
            _ => {}
        }
    }
    s
}

/// Extract the trailing identifier from a member-access expression.
/// For `$this->foo->bar`, returns `"bar"`.