Planned lessonJNR-043-L03

Parameterized tests

Lesson 3 of 6
Junior

On This Lesson 4 topics

In this lesson
Planned topics
Draft outline details
Practice

This lesson is planned. The outline below lists the topics it will cover. The full lesson has not been published yet.

In this lesson

run one test body against many inputs.

Planned topics

@ParameterizedTest replaces copy-pasted tests that differ only in data.
@ValueSource for a list of single values.
@CsvSource for several columns per row (input and expected result).
@MethodSource for complex objects built in a static method.
Use {0}-style placeholders in the name attribute so failures say which row broke.

Draft outline details

Demonstration

java

@ParameterizedTest(name = "{0}% off {1} = {2}")
@CsvSource({"10,100.00,90.00", "0,100.00,100.00", "50,80.00,40.00"})
void discountTable(int pct, BigDecimal price, BigDecimal expected) {
    assertEquals(0, expected.compareTo(calc.discounted(price, pct)));
}

Check your understanding

Which source fits a table of input/expected pairs?

Show answer

@CsvSource.

Practice

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