Added queries testing nested joins

[shinyvision]

Added tests to check whether nested joins are working. These work with my nested join implementations in jackalope/jackalope-doctrine-dbal and phpcr/phpcr-utils

• test nested joins jackalope/jackalope-jackrabbit#131
• Add the possibility of using nested joins jackalope/jackalope-doctrine-dbal#318

[lsmith77]

@richard-fizz ok great .. now can you adjust your composer.json in jackalope/jackalope-doctrine-dbal#318 to use your branch in your repository (see also https://getcomposer.org/doc/05-repositories.md#using-private-repositories)? this way we can automatically verify that your code passes the tests.

ideally you would then also create a similar PR for https://github.com/jackalope/jackalope-jackrabbit

once we have confirmed that your tests pass with both we will merge this PR and create a new tag. you will then have to update your PRs again to use this new tag instead of your own branch.

[shinyvision]

Pushed the modified composer.json to jackalope/jackalope-doctrine-dbal#318.

[dbu]

can you please add one test that is actually run against the repository? the tests you add so far are good, they test the parser and converter. but we should have one in QuerySql2OperationsTest, along the lines of testQueryJoinWithAlias https://github.com/phpcr/phpcr-api-tests/blob/master/tests/Query/QuerySql2OperationsTest.php#L168 - maybe call it testQueryJoinNested ? (no need to test all the other join situations with nested, just one more that does a nested join)

[shinyvision]

Done. Did find one more issue using the new test and solved it right away. Should work properly now.

[dbu]

the tests work with jackalope-jackrabbit as well. can you please squash the commits into one? then i can merge this and tag a version that we can use in jackalope

[shinyvision]

Did I squash the commits properly...? Never done it before.

[dbu]

no, not really ;-)
but i do the squash on the command line. what i did is:

git log # look for the first commit that is already in master
git rebase -i 4816315a3cbf5773fc55c53cdac135aeffff1957 # commit id i found in the log
# replace the `pick` by `squash` for all but the first line, save and exit
# look at the commit messages that are shown, only keep the relevant commit comment

now i have a clean history. if i was the author, i would now git push -f origin HEAD to update my fork branch with the squashed commits. with -f git would give me an error as my local history is different from upstream. git pull or git pull --rebase is not the right thing to do now, as that would make the squashing pointless. we do want to get rid of the detailed history of the branch we squashed...

as it is, i merged the PR on the command line and pushed as 772f2df