How do you create a Live Template for Assertions.assertThrows?

Question

I am converting somewhere around 1000 JUnit tests with

@Test(expected=SomeException.class)
public void testIt() throws SomeException {
  doSomeStuff();
}

to JUnit Jupiter API's

@Test
void testIt() {
  Assertions.assertThrows(SomeException.class, () -> {
    doSomeStuff();    
  });
}

In Intellij, I know there is some "Surround With" magic, Live Templates, or something that can make this process a little more automated?

I could always write a script or something, but I figure there's probably a way to utilize Intellij's built-in functionality to make this easier.

Any ideas?

Answer 1

One way of migration multiple Junit4 tests to Junit5 is OpenRewrite.

It will have multiple predefined recipes for common tasks like Migrating Junit4 to Junit5.

If you have a maven project without spring, you can add the following to your pom.xml.

<build>
  <plugins>
    <plugin>
      <groupId>org.openrewrite.maven</groupId>
      <artifactId>rewrite-maven-plugin</artifactId>
      <version>4.44.0</version>
      <configuration>
        <activeRecipes>
            <recipe>org.openrewrite.java.testing.junit5.JUnit5BestPractices</recipe>
        </activeRecipes>
      </configuration>
      <dependencies>
        <dependency>
          <groupId>org.openrewrite.recipe</groupId>
          <artifactId>rewrite-testing-frameworks</artifactId>
          <version>1.36.0</version>
        </dependency>
      </dependencies>
    </plugin>
  </plugins>
</build>

Quick explanation:

<activeRecipes>
   <recipe>org.openrewrite.java.testing.junit5.JUnit5BestPractices</recipe>
</activeRecipes>

This part activates the rewrite junit recipe, which is in the dependency org.openrewrite.recipe:rewrite-testing-frameworks.

If you are using Spring or Spring-Boot you will need the active recipe org.openrewrite.java.spring.boot2.SpringBoot2JUnit4to5Migration and the following dependency.

<dependency>
  <groupId>org.openrewrite.recipe</groupId>
  <artifactId>rewrite-spring</artifactId>
  <version>4.35.0</version>
</dependency>

If you are using Gradle, you should check out the offical documenation.

Via mvn rewrite:dryRun you can see the results in a .patch file.

Via mvn rewrite:run the migration will be done. If you have a VCS, you can always run without doing a dry run, because you can see the diff in your VCS' diff tool.