Usage of @TestCaseName with @FileParameters in JUnitParams

Question

I use JUnit4 with JUnitParams for testing and I want to know more about the usage of the @TestCaseName annotation. I understand the usage of @TestCaseName with the @Parameters annotation, but I want to know about how to use @TestCaseName with the @FileParmeters annotation.

Answer 1

@TestCaseName allows you to modify how the name of the test case is presented in reports (eg. in your IDE or in the Maven Surefire report). The default naming is {method}({params}) [{index}]. You can use placeholders to create your own test case names. See Javadoc of junitparams.naming.TestCaseName#value:

A template of the individual test case name. This template can contain macros, which will be substituted by their actual values at runtime.

Supported macros are:

• {index} - index of parameters set (starts from zero). Hint: use it to avoid names duplication.
• {params} - parameters set joined by comma.
• {method} - testing method name.
• {0}, {1}, {2} - single parameter by index in current parameters set. If there is no parameter with such index, it will use empty string.

Lets assume, that we are testing Fibonacci sequence generator. We have a test with the following signature

@Parameters({ "0,1", "8,34" })
public void testFibonacci(int indexInSequence, int expectedNumber) { ... }

Here are some examples, that can be used as a test name template:

• {method}({params}) => testFibonacci(0, 1), testFibonacci(8, 34)
• fibonacci({0}) = {1} => fibonacci(0) = 1, fibonacci(8) = 34
• {0} element should be {1} => 0 element should be 1, 8 element should be 34
• Fibonacci sequence test #{index} => Fibonacci sequence test #0, Fibonacci sequence test #1

@FileParameters does not have any relation to @TestCaseName - it's simply a way to provide parameters to a test method from a file. Using the example above, instead of @Parameters you could use @FileParameters("/path/to/file.txt") and have a /path/to/file.txt with content

0,1
8,34

to achieve the same results.