[JENKINS-2111] Integration test of new workspace naming strategy

[jglick]

Subsumes #81. Downstream of jenkinsci/branch-api-plugin#129 and jenkinsci/jenkins-test-harness#113. Amends #33.

[jglick]

Although problems with workspace under test path length are alleviated, this does not help with multibranch Git cache directories. Given lack of JENKINS-2111 on ci.jenkins.io we still have paths like this (~261 chars):

C:\Jenkins\workspace\ow-multibranch-plugin_PR-82-BSJ4LFEA7MEUSVP4BCGHOX2AU52YW43MRBOVGLNUAHDCOQOBWQJA\target\tmp\junit6771207305189317597\junit6679612002461486435\caches\git-240b113e7fedee91380b6c5d51b19944\.git\objects\a0\f11b48e0f348cfa79b846b910c3e846c87f2b3

causing a failure here:

	at org.jenkinsci.plugins.gitclient.CliGitAPIImpl.launchCommandIn(CliGitAPIImpl.java:1990)
	at org.jenkinsci.plugins.gitclient.CliGitAPIImpl.launchCommandWithCredentials(CliGitAPIImpl.java:1709)
	at org.jenkinsci.plugins.gitclient.CliGitAPIImpl.access$300(CliGitAPIImpl.java:72)
	at org.jenkinsci.plugins.gitclient.CliGitAPIImpl$1.execute(CliGitAPIImpl.java:400)
	at jenkins.plugins.git.AbstractGitSCMSource.doRetrieve(AbstractGitSCMSource.java:351)
	at jenkins.plugins.git.AbstractGitSCMSource.retrieve(AbstractGitSCMSource.java:539)
	at jenkins.scm.api.SCMSource._retrieve(SCMSource.java:357)
	at jenkins.scm.api.SCMSource.fetch(SCMSource.java:267)
	at jenkins.branch.MultiBranchProject.computeChildren(MultiBranchProject.java:633)
	at …

The path under .git/ is outside our control; the subdirectory under caches/ cannot be safely shortened; but it looks like the Jenkins root dir is too long when using RestartableJenkinsRule. I will see if I can fix that.

[jglick]

Possibly AbstractSampleDVCSRepoRule.before could also use tmp.getRoot() rather than tmp.newFolder(), though this does not appear to matter in these tests at least.

[vivek]

@svanoort @dwnusbaum I think this pr is ready to merge? It’s approved since over month.

[jglick]

Well it is downstream of jenkinsci/branch-api-plugin#129 which would have to be merged first.