src/vs/editor/contrib/comment/lineCommentCommand.ts/LineCommentCommand/_executeBlockComment
class LineCommentCommand:	private _executeBlockComment(model: ITextModel, builder: IEditOperationBuilder, s: Selection): void {
		model.tokenizeIfCheap(s.startLineNumber);
		let languageId = model.getLanguageIdAtPosition(s.startLineNumber, 1);
		let config = LanguageConfigurationRegistry.getComments(languageId);
		if (!config || !config.blockCommentStartToken || !config.blockCommentEndToken) {
			// Mode does not support block comments
			return;
		}

		const startToken = config.blockCommentStartToken;
		const endToken = config.blockCommentEndToken;

		let ops = this._attemptRemoveBlockComment(model, s, startToken, endToken);
		if (!ops) {
			if (s.isEmpty()) {
				const lineContent = model.getLineContent(s.startLineNumber);
				let firstNonWhitespaceIndex = strings.firstNonWhitespaceIndex(lineContent);
				if (firstNonWhitespaceIndex === -1) {
					// Line is empty or contains only whitespace
					firstNonWhitespaceIndex = lineContent.length;
				}
				ops = BlockCommentCommand._createAddBlockCommentOperations(
					new Range(s.startLineNumber, firstNonWhitespaceIndex + 1, s.startLineNumber, lineContent.length + 1),
					startToken,
					endToken,
					this._insertSpace
				);
			} else {
				ops = BlockCommentCommand._createAddBlockCommentOperations(
					new Range(s.startLineNumber, model.getLineFirstNonWhitespaceColumn(s.startLineNumber), s.endLineNumber, model.getLineMaxColumn(s.endLineNumber)),
					startToken,
					endToken,
					this._insertSpace
				);
			}

			if (ops.length === 1) {
				// Leave cursor after token and Space
				this._deltaColumn = startToken.length + 1;
			}
		}
		this._selectionId = builder.trackSelection(s);
		for (const op of ops) {
			builder.addEditOperation(op.range, op.text);
		}
	}