src/vs/editor/contrib/comment/browser/lineCommentCommand.ts/LineCommentCommand/_gatherPreflightData
class LineCommentCommand:	public static _gatherPreflightData(type: Type, insertSpace: boolean, model: ITextModel, startLineNumber: number, endLineNumber: number, ignoreEmptyLines: boolean, ignoreFirstLine: boolean, languageConfigurationService: ILanguageConfigurationService): IPreflightData {
		const lines = LineCommentCommand._gatherPreflightCommentStrings(model, startLineNumber, endLineNumber, languageConfigurationService);
		if (lines === null) {
			return {
				supported: false
			};
		}

		return LineCommentCommand._analyzeLines(type, insertSpace, model, lines, startLineNumber, ignoreEmptyLines, ignoreFirstLine, languageConfigurationService);
	}