src/vs/workbench/services/untitled/common/untitledTextEditorService.ts/UntitledTextEditorService/doCreateOrGet
class UntitledTextEditorService:	private doCreateOrGet(options: IInternalUntitledTextEditorOptions = Object.create(null)): UntitledTextEditorModel {
		const massagedOptions = this.massageOptions(options);

		// Return existing instance if asked for it
		if (massagedOptions.untitledResource && this.mapResourceToModel.has(massagedOptions.untitledResource)) {
			return this.mapResourceToModel.get(massagedOptions.untitledResource)!;
		}

		// Create new instance otherwise
		return this.doCreate(massagedOptions);
	}