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Issue 956: Migrate tests from JUnit4 to JUnit5

Vincent CUCCHIETTI requested to merge vcucchie/orekit:issue-956 into develop


Hey everyone,

This merge request aims to migrate all Orekit tests from JUnit4 to JUnit5.

I apologize in advance for the mess in my commits, i started from the wrong branch so i had to delete a few things (still learning git).

Process summary

In order to migrate all tests, i initially used a macro available in IntelliJ which did part of the work. Lots of CTRL + R were also used to replace old assertions with their new equivalent.

The Pom now uses the following dependencies:

  • junit-jupiter-api (v5.9.0) (essentially the core of JUnit5)
  • junit-jupiter-engine (v5.9.0) (needed because of the maven surefire plugin 2.22.0+)
  • hamcrest-library (v2.2) (was initially integrated in JUnit4 but is now independent)

Exception tests

From there i mainly had to manually replace tests that expected an exception to be thrown, which used :

@Test(expected = Exception.class)
public void shouldRaiseAnException() throws Exception {
    // ...

By the JUnit5 equivalent :

public void shouldRaiseAnException() throws Exception {
    Assertions.assertThrows(Exception.class, () -> {

Temporary folder & Rule

The other tests where i had to manually intervene were the tests that used the TemporaryFolder class. In this case, the JUnit5 equivalent is the @TempDir annotation. For example, if we had :

class SomeTest {

    TemporaryFolder tmp = new TemporaryFolder();

   // tests ...

Then it was replaced with :

class SomeTest {

    Path(or File) directory;

   // tests ...


I took the opportunity to fix some documentation that didn't use some parameters anymore or with different names.


For those interested in the detailed process, here is what i used to do the migration:

Edited by Vincent CUCCHIETTI

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