[PATCH] diff-tree: fix crash when used with --remerge-diff
From: blanet via GitGitGadget <hidden>
Date: 2024-08-08 13:20:54
Subsystem:
the rest · Maintainer:
Linus Torvalds
From: Xing Xin <redacted>
When using "git-diff-tree" to get the tree diff for merge commits with
the diff format set to `remerge`, a bug is triggered as shown below:
$ git diff-tree -r --remerge-diff 363337e6eb
363337e6eb812d0c0d785ed4261544f35559ff8b
BUG: log-tree.c:1006: did a remerge diff without remerge_objdir?!?
This bug is reported by `log-tree.c:do_remerge_diff`, where a bug check
added in commit 7b90ab467a (log: clean unneeded objects during log
--remerge-diff, 2022-02-02) detects the absence of `remerge_objdir` when
attempting to clean up temporary objects generated during the remerge
process.
After some further digging, I find that the remerge-related diff options
were introduced in db757e8b8d (show, log: provide a --remerge-diff
capability, 2022-02-02), which also affect the setup of `rev_info` for
"git-diff-tree", but were not accounted for in the original
implementation (inferred from the commit message).
This commit fixes the bug by adding initialization logic for
`remerge_objdir` in `builtin/diff-tree.c`, mirroring the logic in
`builtin/log.c:cmd_log_walk_no_free`. A final cleanup for
`remerge_objdir` is also included.
Signed-off-by: Xing Xin <redacted>
---
diff-tree: fix crash when used with --remerge-diff
Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-1771%2Fblanet%2Fxx%2Ffix-diff-tree-crash-on-remerge-v1
Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-1771/blanet/xx/fix-diff-tree-crash-on-remerge-v1
Pull-Request: https://github.com/gitgitgadget/git/pull/1771
builtin/diff-tree.c | 13 +++++++++++++
t/t4069-remerge-diff.sh | 35 +++++++++++++++++++++++++++++++++++
2 files changed, 48 insertions(+)
diff --git a/builtin/diff-tree.c b/builtin/diff-tree.c
index 0d3c611aac0..813be486dad 100644
--- a/builtin/diff-tree.c
+++ b/builtin/diff-tree.c@@ -9,6 +9,7 @@ #include "repository.h" #include "revision.h" #include "tree.h" +#include "tmp-objdir.h" static struct rev_info log_tree_opt;
@@ -166,6 +167,13 @@ int cmd_diff_tree(int argc, const char **argv, const char *prefix) opt->diffopt.rotate_to_strict = 1; + if (opt->remerge_diff) { + opt->remerge_objdir = tmp_objdir_create("remerge-diff"); + if (!opt->remerge_objdir) + die(_("unable to create temporary object directory")); + tmp_objdir_replace_primary_odb(opt->remerge_objdir, 1); + } + /* * NOTE! We expect "a..b" to expand to "^a b" but it is * perfectly valid for revision range parser to yield "b ^a",
@@ -230,5 +238,10 @@ int cmd_diff_tree(int argc, const char **argv, const char *prefix) diff_free(&opt->diffopt); } + if (opt->remerge_diff) { + tmp_objdir_destroy(opt->remerge_objdir); + opt->remerge_objdir = NULL; + } + return diff_result_code(&opt->diffopt); }
diff --git a/t/t4069-remerge-diff.sh b/t/t4069-remerge-diff.sh
index 07323ebafe0..ca8f999caba 100755
--- a/t/t4069-remerge-diff.sh
+++ b/t/t4069-remerge-diff.sh@@ -110,6 +110,41 @@ test_expect_success 'can filter out additional headers with pickaxe' ' test_must_be_empty actual ' +test_expect_success 'remerge-diff also works for git-diff-tree' ' + # With a clean merge + git diff-tree -r -p --remerge-diff --no-commit-id bc_resolution >actual && + test_must_be_empty actual && + + # With both a resolved conflict and an unrelated change + cat <<-EOF >tmp && + diff --git a/numbers b/numbers + remerge CONFLICT (content): Merge conflict in numbers + index a1fb731..6875544 100644 + --- a/numbers + +++ b/numbers + @@ -1,13 +1,9 @@ + 1 + 2 + -<<<<<<< b0ed5cb (change_a) + -three + -======= + -tres + ->>>>>>> 6cd3f82 (change_b) + +drei + 4 + 5 + 6 + 7 + -eight + +acht + 9 + EOF + sed -e "s/[0-9a-f]\{7,\}/HASH/g" tmp >expect && + git diff-tree -r -p --remerge-diff --no-commit-id ab_resolution >tmp && + sed -e "s/[0-9a-f]\{7,\}/HASH/g" tmp >actual && + test_cmp expect actual +' + test_expect_success 'setup non-content conflicts' ' git switch --orphan base &&
base-commit: 406f326d271e0bacecdb00425422c5fa3f314930 -- gitgitgadget