dirs._addpath: reinstate use of Py_CLEAR
I changed this to an explicit Py_DECREF + set to null in 6f0e6fa9fdd7. This was
a silly misunderstanding on my part -- for some reason I thought Py_CLEAR set
its argument to null only if its refcount reached 0. Turns out that's not
actually the case -- Py_CLEAR is just Py_DECREF + set to null with some
additional precautions around destructors that aren't relevant here.
The real bug that 6f0e6fa9fdd7 fixed was the fact that we were mutating the
string after setting it in the Python dictionary.
Check that entry is added to .hg/requires
$ hg --config experimental.manifestv2=True init repo
$ cd repo
$ grep manifestv2 .hg/requires
manifestv2
Set up simple repo
$ echo a > file1
$ echo b > file2
$ echo c > file3
$ hg ci -Aqm 'initial'
$ echo d > file2
$ hg ci -m 'modify file2'
Check that 'hg verify', which uses manifest.readdelta(), works
$ hg verify
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
3 files, 2 changesets, 4 total revisions
Check that manifest revlog is smaller than for v1
$ hg debugindex -m
rev offset length base linkrev nodeid p1 p2
0 0 81 0 0 57361477c778 000000000000 000000000000
1 81 33 0 1 aeaab5a2ef74 57361477c778 000000000000