Automated tests

[gd-tmagrys]

Implementing story:

https://github.com/griddynamics/nexus-replication-plugin/issues/16

This PR overrides:

https://github.com/griddynamics/nexus-replication-plugin/pull/24

Please review and merge if possible.

[ctapobep]

@gd-tmagrys the first 2 commits here are outdated, is that right?

[gd-tmagrys]

Yes, because this work was created on top of #29 . I'll rebase it on master.

[gd-tmagrys]

@ctapobep, I rebased work regarding this PR on master. Feel free to review.

[ctapobep]

Hm. But I see classes like JerseyClientFactory added within this commit, so it's not just tests. I haven't looked in much details at the tests, but the overall impression is still that we mock too much..

Also, couple of test design comments:

• To follow BDD test names should state "if blah-blah then blah blah" or "blah blah should do blah blah". In this case it's clear what behavior test expects. And it's not clear what is expected in the test with name testPostForTwoMatchedRepositories
• Tests should be small. If you have a lot of preparations, you can factor it out into separate methods. E.g. this code:

M2Repository repository = mock(M2Repository.class);
when(repository.getRemoteUrl()).thenReturn("http://localhost:8081/nexus/content/repositories/snapshots/");
when(repository.getId()).thenReturn("replica-1");
when(repository.getArtifactStoreHelper()).thenReturn(artifactStoreHelper);
repositories.add(repository);

Can be placed in method: private M2Repository repo(String id, String url). There may be couple of overloaded methods like private M2Repository repo(String id) and private M2Repository repo() that return repos with default or random IDs/URLs.

[gd-tmagrys]

@ctapobep, I hope that I fix things you've mentioned in my last commit.