Function _replace_chars_common

core/string/ustring.cpp:4113–4164

template <class T>
static String _replace_chars_common(const String &p_this, const T *p_keys, int p_keys_len, char32_t p_with) {
	ERR_FAIL_COND_V_MSG(p_with == 0, p_this, "`with` must not be the NUL character.");

	// Delegate if p_keys is a single element.
	if (p_keys_len == 1) {
		return p_this.replace_char(*p_keys, p_with);
	} else if (p_keys_len == 0) {
		return p_this;
	}

	int len = p_this.length();
	if (len == 0) {
		return p_this;
	}

	int index = 0;
	const char32_t *old_ptr = p_this.ptr();
	for (; index < len; ++index) {
		if (_contains_char(old_ptr[index], p_keys, p_keys_len)) {
			break;
		}
	}

	// If no occurrence of `keys` was found, return this.
	if (index == len) {
		return p_this;
	}

	// If we found at least one occurrence of `keys`, create new string.
	String new_string;
	new_string.resize_uninitialized(len + 1);
	char32_t *new_ptr = new_string.ptrw();

	// Copy part of input before `key`.
	memcpy(new_ptr, old_ptr, index * sizeof(char32_t));

	new_ptr[index] = p_with;

	// Copy or replace rest of input.
	for (++index; index < len; ++index) {
		const char32_t old_char = old_ptr[index];
		if (_contains_char(old_char, p_keys, p_keys_len)) {
			new_ptr[index] = p_with;
		} else {
			new_ptr[index] = old_char;
		}
	}

	new_ptr[index] = 0;

	return new_string;
}

String String::replace_chars(const String &p_keys, char32_t p_with) const {
	return _replace_chars_common(*this, p_keys.ptr(), p_keys.length(), p_with);