On Mac's HFS where git sets core.precomposeUnicode to true automatically
by git init/clone, when a user creates a simple unicode refname (in NFC
format) such as españa:
$ git branch españa
different commands would display the branch name differently. For
example, git branch, git log --decorate, and git fast-export all used
65 73 70 61 c3 b1 61 (or "espa\xc3\xb1a")
(NFC form) while show-ref would use
65 73 70 61 6e cc 83 61 (or "espan\xcc\x83a")
(NFD form). A stress test for git filter-repo was tripped up by this
inconsistency, though digging in I found that the problems could
compound; for example, if the user ran
$ git pack-refs --all
and then tried to check out the branch, they would be met with:
$ git checkout españa
error: pathspec 'españa' did not match any file(s) known to git
$ git checkout españa --
fatal: invalid reference: españa
$ git branch
españa
* master
Note that the user could run the `git branch` command first and copy and
paste the `españa` portion of the output and still see the same two
errors. Also, if the user added --no-prune to the pack-refs command,
then they would see three branches: master, españa, and españa (those
last two are NFC vs. NFD forms, even if they render the same).
Further, if the user had the `españa` branch checked out before
running `git pack-refs --all`, the user would be greeted with (note
that I'm trimming trailing output with an ellipsis):
$ git rev-parse HEAD
fatal: ambiguous argument 'HEAD': unknown revision or path...
$ git status
On branch españa
No commits yet...
Or worse, if the user didn't check this stuff first, running `git
commit` will create a new commit with all changes of all of history
being squashed into it.
In addition to pack-refs, one could also get into this state with
upload-pack or anything that calls either pack-refs or upload-pack (e.g.
gc or clone).
Add code in a few places (pack-refs, show-ref, upload-pack) to check and
honor the setting of core.precomposeUnicode to avoid these bugs.
Signed-off-by: Elijah Newren <newren@xxxxxxxxx>
---
Changes since v1:
* Excised unnecessary portion of the first sentence of the commit message
builtin/pack-refs.c | 2 ++
builtin/show-ref.c | 3 +++
upload-pack.c | 2 ++
3 files changed, 7 insertions(+)
diff --git a/builtin/pack-refs.c b/builtin/pack-refs.c
index f3353564f9..cfbd5c36c7 100644
--- a/builtin/pack-refs.c
+++ b/builtin/pack-refs.c
@@ -1,4 +1,5 @@
#include "builtin.h"
+#include "config.h"
#include "parse-options.h"
#include "refs.h"
#include "repository.h"
@@ -16,6 +17,7 @@ int cmd_pack_refs(int argc, const char **argv, const char *prefix)
OPT_BIT(0, "prune", &flags, N_("prune loose refs (default)"), PACK_REFS_PRUNE),
OPT_END(),
};
+ git_config(git_default_config, NULL);
if (parse_options(argc, argv, prefix, opts, pack_refs_usage, 0))
usage_with_options(pack_refs_usage, opts);
return refs_pack_refs(get_main_ref_store(the_repository), flags);
diff --git a/builtin/show-ref.c b/builtin/show-ref.c
index 6a706c02a6..6456da70cc 100644
--- a/builtin/show-ref.c
+++ b/builtin/show-ref.c
@@ -1,5 +1,6 @@
#include "builtin.h"
#include "cache.h"
+#include "config.h"
#include "refs.h"
#include "object-store.h"
#include "object.h"
@@ -182,6 +183,8 @@ static const struct option show_ref_options[] = {
int cmd_show_ref(int argc, const char **argv, const char *prefix)
{
+ git_config(git_default_config, NULL);
+
argc = parse_options(argc, argv, prefix, show_ref_options,
show_ref_usage, 0);
diff --git a/upload-pack.c b/upload-pack.c
index d098ef5982..159f751ea4 100644
--- a/upload-pack.c
+++ b/upload-pack.c
@@ -1064,6 +1064,8 @@ static int upload_pack_config(const char *var, const char *value, void *unused)
allow_ref_in_want = git_config_bool(var, value);
} else if (!strcmp("uploadpack.allowsidebandall", var)) {
allow_sideband_all = git_config_bool(var, value);
+ } else if (!strcmp("core.precomposeunicode", var)) {
+ precomposed_unicode = git_config_bool(var, value);
}
if (current_config_scope() != CONFIG_SCOPE_REPO) {
--
2.21.0.503.g24b69a0db9
