How to use the jsonc-parser.ScanError.UnexpectedEndOfComment function in jsonc-parser

if (stack.length > 0 && stack[stack.length - 1].kind === kind) {
					let range = stack.pop();
					let line = document.positionAt(scanner.getTokenOffset()).line;
					if (range && line > range.startLine + 1 && prevStart !== range.startLine) {
						range.endLine = line - 1;
						addRange(range);
						prevStart = range.startLine;
					}
				}
				break;
			}

			case SyntaxKind.BlockCommentTrivia: {
				let startLine = document.positionAt(scanner.getTokenOffset()).line;
				let endLine = document.positionAt(scanner.getTokenOffset() + scanner.getTokenLength()).line;
				if (scanner.getTokenError() === ScanError.UnexpectedEndOfComment && startLine + 1 < document.lineCount) {
					scanner.setPosition(document.offsetAt(Position.create(startLine + 1, 0)));
				} else {
					if (startLine < endLine) {
						addRange({ startLine, endLine, kind: FoldingRangeKind.Comment });
						prevStart = startLine;
					}
				}
				break;
			}

			case SyntaxKind.LineCommentTrivia: {
				let text = document.getText().substr(scanner.getTokenOffset(), scanner.getTokenLength());
				let m = text.match(/^\/\/\s*#(region\b)|(endregion\b)/);
				if (m) {
					let line = document.positionAt(scanner.getTokenOffset()).line;
					if (m[1]) { // start pattern match