[JENKINS-75410] extends AbstractGitSCMSource for BitbucketSCMSource

[gboucherie]

Change BitbucketSCMSource extended class to AbstractGitSCMSource to be fully compatible with Pipeline: Multibranch build strategy extension.
Otherwise the srategy extension plugin throws an exception when trying to get the changeset to apply the strategy defined in the job.

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[nfalco79]

Otherwise the srategy extension plugin throws an exception when trying to get the changeset to apply the strategy defined in the job.

Which is this exception? Why the "Multibranch build strategy extension" does not use the interface API instead of the abstract class?

[gboucherie]

The exception is a ClassCastException because on this line when calling the build method the BitbucketSourceScm cannot be cast to AbstractGitSCMSource.

I also try to change the code in other plugin to get the SCMFileSystem.Builder corresponding to the current SCMSource but the SCMFileSystem must implement the changesSince() methods for the plugin to get the change set. And implementation BitbucketSCMFileSystem doesn't leading to another exception.

[nfalco79]

but the SCMFileSystem must implement the changesSince()

See JENKINS-49417.
AbstractGit....class to build the changelog rely on git cli operation (that why I would not get this way) where maybe code is not yet cloned or checkout (insted of the lightweight checkout using API to get diff).

[gboucherie]

Ok, I understand your point. Thanks