If none is given, we fall back to whatever accessor we get from the
store.
To display which paths actually contain the references leading to
e.g. a cycle or triggering a disallowedRequisites error, we'd
potentially have to look into the chroot from the previously finished
build. This behavior should not be part of the local accessor by
default, but part of a "special" accessor. This change allows using such
an accessor for `genGraphString()`.
Now that we inject the accessor from the outside, we have to mock it
anyways in the tests. Hence, this also adds a testcase for the
precise=True case.
Change-Id: I58465fb944776c2b0262ba054d1f296ed2ae3406
Maximilian Bosch
2175d007e5