Hidden testable code 4

easyToTest-realCode.ts

// This function needs only one test
function hardToTest() {
	let data = requestExternalServer()
	let lang = persistence.get(data.id))

	let langToUpdate = makeLangToUpdate(lang)

	return persistence.update(data.id, langToUpdate)
}

// This functionc can be thouroughly tested
function makeLangToUpdate(versionLangs, lang) {

	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;
	        }
	    });
	});
}