src/vs/editor/common/core/stringBuilder.ts/StringBuilder/appendString
class StringBuilder:	public appendString(str: string): void {
		const strLen = str.length;

		if (this._bufferLength + strLen >= this._capacity) {
			// This string does not fit in the remaining buffer space

			this._flushBuffer();
			this._completedStrings![this._completedStrings!.length] = str;
			return;
		}

		for (let i = 0; i < strLen; i++) {
			this._buffer[this._bufferLength++] = str.charCodeAt(i);
		}
	}