Unit Test Parameterized

What it does

When your agent uses it

• Writing data-driven Java tests
• Multiple test cases from single method
• Boundary value analysis

Example prompts

• “Use the unit-test-parameterized skill to provide parameterized testing patterns with JUnit 5, generates data-driven unit tests using…”
• “/unit-test-parameterized”

Requirements

• Pre-approved tools (allowed-tools): Read, Write, Bash, Glob, Grep

Workflow steps

5 steps, taken from the first numbered list in SKILL.md.

1. 1Add dependency: Ensure junit-jupiter-params is on test classpath (included in junit-jupiter)
2. 2Choose source: @ValueSource for simple values, @CsvSource for tabular data, @MethodSource for complex objects
3. 3Match parameters: Test method parameters must match data source types
4. 4Set display names: Use name = "{0}..." for readable output
5. 5Validate: Run ./gradlew test --info or mvn test and verify all parameter combinations execute

What it can do on your machine

Read from SKILL.md and the folder at commit fe73fb3. It shows what the files ask for, not the result of running them.

• Tool permissions

  Pre-approves these tools, so the agent can use them without asking each time:

  • Read
  • Write
  • Bash
  • Glob
  • Grep

  From allowed-tools in the SKILL.md frontmatter.

• Runs code

  Shell commands in SKILL.md call:

  • mvn

  From the folder's file list and the shell code blocks in SKILL.md.

• Network

  Links to these hosts (documentation or services it may open):

  • junit.org

  From URLs in SKILL.md, links to its own repository left out.

• Credentials

  Names no API keys, tokens, secrets or passwords.

  From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.

Context cost

Unit Test Parameterized loads about 1.6k tokens when it runs. Until then it costs about 88 tokens; SKILL.md has 299 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it

~88

When it runs · the whole SKILL.md, loaded when a task matches

~1.6k

Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.

Safety

• NotePre-approves every shell command (allowed-tools: Bash)SKILL.md

  allowed-tools: Read, Write, Bash, Glob, Grep

Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.

SKILL.md

The full file from giuseppe-trisciuoglio/developer-kit at commit fe73fb3, republished under its MIT licence (© giuseppe-trisciuoglio). 299 words, ~1,592 tokens.

name

unit-test-parameterized

description

Provides parameterized testing patterns with JUnit 5, generates data-driven unit tests using @ParameterizedTest, @ValueSource, @CsvSource, @MethodSource. Creates tests that run the same logic with multiple input values. Use when writing data-driven Java tests, multiple test cases from single method, or boundary value analysis.

allowed-tools

Read, Write, Bash, Glob, Grep

<!-- Maven -->
<dependency>
  <groupId>org.junit.jupiter</groupId>
  <artifactId>junit-jupiter</artifactId>
  <scope>test</scope>
</dependency>

// Gradle
testImplementation("org.junit.jupiter:junit-jupiter")

import org.junit.jupiter.params.ParameterizedTest;
import org.junit.jupiter.params.provider.ValueSource;
import static org.assertj.core.api.Assertions.*;

@ParameterizedTest
@ValueSource(strings = {"hello", "world", "test"})
void shouldCapitalizeAllStrings(String input) {
  assertThat(StringUtils.capitalize(input)).isNotEmpty();
}

@ParameterizedTest
@ValueSource(ints = {1, 2, 3, 4, 5})
void shouldBePositive(int number) {
  assertThat(number).isPositive();
}

@ParameterizedTest
@ValueSource(ints = {Integer.MIN_VALUE, -1, 0, 1, Integer.MAX_VALUE})
void shouldHandleBoundaryValues(int value) {
  assertThat(Math.incrementExact(value)).isGreaterThan(value);
}

import org.junit.jupiter.params.ParameterizedTest;
import org.junit.jupiter.params.provider.CsvSource;

@ParameterizedTest
@CsvSource({
  "alice@example.com, true",
  "bob@gmail.com,     true",
  "invalid-email,     false",
  "user@,             false",
  "@example.com,       false"
})
void shouldValidateEmailAddresses(String email, boolean expected) {
  assertThat(UserValidator.isValidEmail(email)).isEqualTo(expected);
}

import org.junit.jupiter.params.ParameterizedTest;
import org.junit.jupiter.params.provider.MethodSource;
import java.util.stream.Stream;

@ParameterizedTest
@MethodSource("additionTestCases")
void shouldAddNumbersCorrectly(int a, int b, int expected) {
  assertThat(Calculator.add(a, b)).isEqualTo(expected);
}

static Stream<Arguments> additionTestCases() {
  return Stream.of(
    Arguments.of(1, 2, 3),
    Arguments.of(0, 0, 0),
    Arguments.of(-1, 1, 0),
    Arguments.of(100, 200, 300)
  );
}

@ParameterizedTest
@EnumSource(Status.class)
void shouldHandleAllStatuses(Status status) {
  assertThat(status).isNotNull();
}

@ParameterizedTest
@EnumSource(value = Status.class, names = {"ACTIVE", "INACTIVE"})
void shouldHandleSpecificStatuses(Status status) {
  assertThat(status).isIn(Status.ACTIVE, Status.INACTIVE);
}

@ParameterizedTest(name = "Discount of {0}% should be calculated correctly")
@ValueSource(ints = {5, 10, 15, 20})
void shouldApplyDiscount(int discountPercent) {
  double result = DiscountCalculator.apply(100.0, discountPercent);
  assertThat(result).isEqualTo(100.0 * (1 - discountPercent / 100.0));
}

class RangeValidatorProvider implements ArgumentsProvider {
  @Override
  public Stream<? extends Arguments> provideArguments(ExtensionContext context) {
    return Stream.of(
      Arguments.of(0, 0, 100, true),
      Arguments.of(50, 0, 100, true),
      Arguments.of(-1, 0, 100, false),
      Arguments.of(101, 0, 100, false)
    );
  }
}

@ParameterizedTest
@ArgumentsSource(RangeValidatorProvider.class)
void shouldValidateRange(int value, int min, int max, boolean expected) {
  assertThat(RangeValidator.isInRange(value, min, max)).isEqualTo(expected);
}

@ParameterizedTest
@ValueSource(strings = {"", " ", null})
void shouldThrowExceptionForInvalidInput(String input) {
  assertThatThrownBy(() -> Parser.parse(input))
    .isInstanceOf(IllegalArgumentException.class);
}

© giuseppe-trisciuoglio, MIT. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file

Files

Just SKILL.md in plugins/developer-kit-java/skills/unit-test-parameterized of giuseppe-trisciuoglio/developer-kit.

Open the folder on GitHubat commit fe73fb3