Unit Testing Comes under white box testing technique.
Testing of each line of code / each function / each procedure / each loop is called unit testing.
Taking each function and passing the required parameters / values and expected the desired output will be unit testing.
But it does not mean that always done by a developer. An Exp. white box tester can also perform unit testing but he should have coding knowledge.
Unit testing is done by only developers is wrong. It is basically done by White box testers / Code testers.
Pradeep R
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