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JUnit assertNull to AssertJ

org.openrewrite.java.testing.assertj.JUnitAssertNullToAssertThat

Convert JUnit-style assertNull() to AssertJ's assertThat().isNull().

Recipe source​

GitHub, Issue Tracker, Maven Central

This recipe is available under the Moderne Source Available License.

Example​

Before​
    import org.junit.jupiter.api.Test;

import static org.junit.jupiter.api.Assertions.assertNull;

public class MyTest {
    @Test
    public void test() {
        assertNull(notification());
    }
    private String notification() {
        return null;
    }
}
After​
    import org.junit.jupiter.api.Test;

import static org.assertj.core.api.Assertions.assertThat;

public class MyTest {
    @Test
    public void test() {
        assertThat(notification()).isNull();
    }
    private String notification() {
        return null;
    }
}

Usage​

This recipe has no required configuration options. It can be activated by adding a dependency on org.openrewrite.recipe:rewrite-testing-frameworks in your build file or by running a shell command (in which case no build changes are needed):

  1. Add the following to your build.gradle file:
build.gradle
plugins {
    id("org.openrewrite.rewrite") version("7.6.2")
}

rewrite {
    activeRecipe("org.openrewrite.java.testing.assertj.JUnitAssertNullToAssertThat")
    setExportDatatables(true)
}

repositories {
    mavenCentral()
}

dependencies {
    rewrite("org.openrewrite.recipe:rewrite-testing-frameworks:3.8.0")
}
  1. Run gradle rewriteRun to run the recipe.

See how this recipe works across multiple open-source repositories​

Run this recipe on OSS repos at scale with the Moderne SaaS.

The community edition of the Moderne platform enables you to easily run recipes across thousands of open-source repositories.

Please contact Moderne for more information about safely running the recipes on your own codebase in a private SaaS.

Data Tables​

Source files that had results​

org.openrewrite.table.SourcesFileResults

Source files that were modified by the recipe run.

Column NameDescription
Source path before the runThe source path of the file before the run. null when a source file was created during the run.
Source path after the runA recipe may modify the source path. This is the path after the run. null when a source file was deleted during the run.
Parent of the recipe that made changesIn a hierarchical recipe, the parent of the recipe that made a change. Empty if this is the root of a hierarchy or if the recipe is not hierarchical at all.
Recipe that made changesThe specific recipe that made a change.
Estimated time savingAn estimated effort that a developer to fix manually instead of using this recipe, in unit of seconds.
CycleThe recipe cycle in which the change was made.

Contributors​

Greg Adams, Jacob van Lingen, Patrick Way, Jonathan Schnéider, Knut Wannheden, Patrick, Tim te Beek, Sam Snyder