JUni4のparameterized testをJUnit5に

Java #Kotlin

テスト対象コード

class Calculator() {
    fun add(x: Int, y: Int) = x + y
}

JUnit4

import org.hamcrest.CoreMatchers
import org.hamcrest.MatcherAssert
import org.junit.Test
import org.junit.runner.RunWith
import org.junit.runners.Parameterized
 
@RunWith(Parameterized::class)
internal class CalculatorTest(private val x: Int, private val y: Int, private val expected: Int) {
 
    @Test
    fun test() {
        val calc = Calculator()
        val actual = calc.add(x, y)
        MatcherAssert.assertThat(actual, CoreMatchers.equalTo(expected))
    }
 
    companion object {
        @JvmStatic
        @Parameterized.Parameters
        fun data() = listOf(
                arrayOf(1, 2, 3),
                arrayOf(9, 8, 17),
        )
    }
}

JUnit5

import org.junit.Assert.assertEquals
import org.junit.jupiter.params.ParameterizedTest
import org.junit.jupiter.params.provider.CsvSource
 
internal class CalculatorTest {
 
    @ParameterizedTest
    @CsvSource(
            "1, 2, 3",
            "9, 8, 17",
    )
    fun test(x: Int, y: Int, expected: Int) {
        val calc = Calculator()
        val actual = calc.add(x, y)
        assertEquals(expected, actual)
    }
 
}

companion object を使う必要がない 簡単なテストケースであれば @CsvSource が使えるため、すっきりする