[PATCH 0/8] commit-graph: segfault & other fixes for broken graphs

["Ævar Arnfjörð Bjarmason" <avarab@gmail.com>]

This one isn't for 2.21.0, these issues are already in v2.20.0, I just
spotted them when looking at & fixing the commit-graph test broken on
NetBSD[1].

This series touches (among other things) some of the same test code,
but merges cleanly with that "dd" fix, and it's not required for
testing it (unless you're on NetBSD).

Instrumenting the commit-graph tests reveals that if you have a broken
commit-graph git will either segfault or abort early with cryptic
errors on such basic commands as "status".

Furthemore, if our graph is corrupt and we've set
core.commitGraph=true we can't even write a new commit-graph, because
writing a new one has grown to implicitly depend on reading the old
one!

This series fixes all of that.

1. https://public-inbox.org/git/20190221192849.6581-3-avarab@gmail.com/

Ævar Arnfjörð Bjarmason (8):
  commit-graph tests: split up corrupt_graph_and_verify()
  commit-graph tests: test a graph that's too small
  commit-graph: fix segfault on e.g. "git status"
  commit-graph: don't early exit(1) on e.g. "git status"
  commit-graph: don't pass filename to load_commit_graph_one_fd_st()
  commit-graph verify: detect inability to read the graph
  commit-graph write: don't die if the existing graph is corrupt
  commit-graph: improve & i18n error messages

 builtin/commit-graph.c  |  23 +++++--
 commit-graph.c          | 132 +++++++++++++++++++++++++++-------------
 commit-graph.h          |   4 ++
 commit.h                |   6 ++
 t/t5318-commit-graph.sh |  48 +++++++++++++--
 5 files changed, 160 insertions(+), 53 deletions(-)

-- 
2.21.0.rc0.258.g878e2cd30e