How can I do the translation testing?
In our application, we have a bunch of translations in different languages, in English, German, Arabic, and Spanish.
I think, 100% Unit testing coverage can be useful to check the translations, because when the app gets bigger and bigger:
Translations tend to cause human error in manual testing.
Testing translation takes a lot of effort and time when manual testing.
The perfect practice is End2End testing. Then, we need to run manual testing for translations as well.
Given that we have 100% coverage on unit test level,how much manual testing for translation is enough? 100% coverage, 30%, etc...
If the coverage depends on some other factors, then how may i calculate the best coverage?
How should we choose our testcases? We can open a page randomly, and check the translations of this page. But, i am not sure if it is the best approach.
If you have any experiance in testing translations, please specify, how did you do it?
I am not sure unit testing is a good way for translation testing. Since what you call a translation is just a static text. It is not built within an algorithm. Normally, when you localize your app for different locales, you describe the text as properties which have different values for different languages. Application then detects the locale and takes the appropriate property values (text in suitable language).
So when you develop a commercial application you usually have original set of Strings. You then pay the native speakers to translate your strings and put a file for particular locale to your app sources or deployment. So then you just cover your app with manual testing or introduce Selenium testing (for web) or other sort of tests. But definitely not Unit Tests.