Add failing test with multiple joins and InlineQuery

[koenpunt]

I'm not sure yet how I should approach this problem, but it seems that somehow where clauses of the inline query are partly reused in the outer query, resulting in invalid SQL.

To clarify, the test result is:

org.opentest4j.AssertionFailedError: 
expected: "SELECT merchants_customers.* FROM merchants_customers JOIN (SELECT customer_details.user_id AS user_id FROM customer_details JOIN merchants_customers ON merchants_customers.user_id = customer_details.user_id) inner ON inner.user_id = merchants_customers.user_id"
 but was: "SELECT merchants_customers.* FROM merchants_customers JOIN (SELECT customer_details.user_id AS user_id FROM customer_details JOIN merchants_customers ON merchants_customers.user_id = customer_details.user_id) inner ON merchants_customers.merchant_id = :merchantId = merchants_customers.user_id"

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[koenpunt]

I've been able to make the test a bit smaller with less conditions and clauses. But after spending quite some time I haven't been able to find what should be changed to let this behave correctly.

Somewhere between ComparisonVisitor.enterNested and ComparisonVisitor.leaveNested the previous comparison is visited again, and causes the incorrect SQL.

Unfortunately I don't know enough about the visitor/delegation setup to find the actual cause.

[schauder]

I created a fresh PR which includes your (simplified) tests plus a fix: #1368