FileReftableStack.addReftable does not match the specifications

[zotttelbart]

Version

7.1.0

Operating System

Windows

Bug description

The implementation of FileReftableStack.addReftable doesn't match the specifications in FileReftableStack.addReftable

The specification says, that a writer have to read the tables.list files to detemine the current tables after the lock is acquired.

Actual behavior

addReftable fails, if the stack is not upToDate.

Expected behavior

After acquire the lock for tables.list the stack should be reload if necessary.

Relevant log output

Other information

With change https://eclipse.gerrithub.io/c/eclipse-jgit/jgit/+/1206683 @msohn try to reload the stack, if necessary. But I don't know, if it is enough in racy conditions. To meet the specification addReftable should call reload or reloadIfNecassary.