skipWhitespace

fn skipWhitespace(self: *@This()) void {
    while (self.cursor < self.input.len) : (self.cursor += 1) {
        switch (self.input[self.cursor]) {
            // Whitespace
            ' ', '\t', '\r' => continue,
            '\n' => {
                if (self.diagnostics) |diag| {
                    diag.line_number += 1;
                    // This will count the newline itself,
                    // which means a straight-forward subtraction will give a 1-based column number.
                    diag.line_start_cursor = self.cursor;
                }
                continue;
            },
            else => return,
        }
    }
}