[PATCH 0/4] merge-tree: handle missing objects correctly

Johannes Schindelin via GitGitGadget
2024-02-06T09:49:45Z

I recently looked into issues where git merge-tree calls returned bogus data
(in one instance returning an empty tree for non-empty merge parents). By
the time I had a look at the corresponding repository, the issue was no
longer reproducible, but a closer look at the code combined with some manual
experimenting turned up the fact that missing tree objects aren't handled as
errors by git merge-tree.

While at it, I added a commit on top that tries to catch all remaining
unchecked parse_tree() calls.

This patch series is based on js/merge-tree-3-trees because I introduced
three unchecked parse_tree() calls in that topic branch.

Johannes Schindelin (4):
merge-tree: fail with a non-zero exit code on missing tree objects
merge-ort: do check `parse_tree()`'s return value
t4301: verify that merge-tree fails on missing blob objects
Always check `parse_tree*()`'s return value

builtin/checkout.c | 19 ++++++++++++++++---
builtin/clone.c | 3 ++-
builtin/commit.c | 3 ++-
builtin/merge-tree.c | 6 ++++++
builtin/read-tree.c | 3 ++-
builtin/reset.c | 4 ++++
cache-tree.c | 4 ++--
merge-ort.c | 16 +++++++++++-----
merge-recursive.c | 3 ++-
merge.c | 5 ++++-
reset.c | 5 +++++
sequencer.c | 4 ++++
t/t4301-merge-tree-write-tree.sh | 24 ++++++++++++++++++++++++
13 files changed, 84 insertions(+), 15 deletions(-)

base-commit: 5f43cf5b2e4b68386d3774bce880b0f74d801635
Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-1651%2Fdscho%2Fmerge-tree-and-missing-objects-v1
Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-1651/dscho/merge-tree-and-missing-objects-v1
Pull-Request: https://github.com/gitgitgadget/git/pull/1651