src/vs/editor/common/cursor/cursorWordOperations.ts/WordOperations/_deleteWordLeftWhitespace
class WordOperations:	protected static _deleteWordLeftWhitespace(model: ICursorSimpleModel, position: Position): Range | null {
		const lineContent = model.getLineContent(position.lineNumber);
		const startIndex = position.column - 2;
		const lastNonWhitespace = strings.lastNonWhitespaceIndex(lineContent, startIndex);
		if (lastNonWhitespace + 1 < startIndex) {
			return new Range(position.lineNumber, lastNonWhitespace + 2, position.lineNumber, position.column);
		}
		return null;
	}