Hidden testable code 3

hardToTest-realCode.ts

function hardToTest() {
	let data = requestExternalServer() // hard to test
	let lang = persistence.get(data.id)) // hard to test

	// below pure transformation logic
	let langToUpdate = {};
	versionsLangs.map((versionLang) => {
		let restPath = versionLang.entity.toRestPath();
	
		lang.dates.langsDates.map(datePayload => {
			if (restPath === datePayload.langRestPath) {
			    langToUpdate[restPath] = langToUpdate[restPath] || {};
			    langToUpdate[restPath].dates = datePayload.payload.dates;
			}
		});
	});
	
	// hard to test again
	return persistence.update(data.id, langToUpdate)
}