The NUnit console will show you which test case failed. Example:
[TestCase("ABK")] [TestCase("bgba")] [TestCase("CBVS")] [TestCase("DSBH")] [TestCase("E")] [TestCase("FJMC")] [TestCase("HBTV2")] [TestCase("JFFC1")] [TestCase("K")] [TestCase("LBHG")] [TestCase("MJCM")] [TestCase("PHJL")] [TestCase("R")] [TestCase("TDPP")] [TestCase("UGV")] [TestCase("VXHC")] [TestCase("YFD")] public void Given_a_main_supplier_categorie_then_it_should_return_a_collection_of_RM_categories(string supplierCategory) {
See attached screenshot. In addition, Resharper has excellent support for unit testing.

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