Automatic re-encoding of commit messages (and dropping of the encoding
header) hurts attempts to do reversible history rewrites (e.g. sha1sum
<-> sha256sum transitions, some subtree rewrites), and seems
inconsistent with the general principle followed elsewhere in
fast-export of requiring explicit user requests to modify the output
(e.g. --signed-tags=strip, --tag-of-filtered-object=rewrite). Add a
--reencode flag that the user can use to specify, and like other
fast-export flags, default it to 'abort'.
Signed-off-by: Elijah Newren <newren@xxxxxxxxx>
---
Documentation/git-fast-export.txt | 7 +++++
builtin/fast-export.c | 46 +++++++++++++++++++++++++++++--
t/t9350-fast-export.sh | 38 +++++++++++++++++++++++--
3 files changed, 85 insertions(+), 6 deletions(-)
diff --git a/Documentation/git-fast-export.txt b/Documentation/git-fast-export.txt
index 64c01ba918..11427acdde 100644
--- a/Documentation/git-fast-export.txt
+++ b/Documentation/git-fast-export.txt
@@ -129,6 +129,13 @@ marks the same across runs.
for intermediary filters (e.g. for rewriting commit messages
which refer to older commits, or for stripping blobs by id).
+--reencode=(yes|no|abort)::
+ Specify how to handle `encoding` header in commit objects. When
+ asking to 'abort' (which is the default), this program will die
+ when encountering such a commit object. With 'yes', the commit
+ message will be reencoded into UTF-8. With 'no', the original
+ encoding will be preserved.
+
--refspec::
Apply the specified refspec to each ref exported. Multiple of them can
be specified.
diff --git a/builtin/fast-export.c b/builtin/fast-export.c
index 66331fa401..c22cef3b2f 100644
--- a/builtin/fast-export.c
+++ b/builtin/fast-export.c
@@ -33,6 +33,7 @@ static const char *fast_export_usage[] = {
static int progress;
static enum { SIGNED_TAG_ABORT, VERBATIM, WARN, WARN_STRIP, STRIP } signed_tag_mode = SIGNED_TAG_ABORT;
static enum { TAG_FILTERING_ABORT, DROP, REWRITE } tag_of_filtered_mode = TAG_FILTERING_ABORT;
+static enum { REENCODE_ABORT, REENCODE_YES, REENCODE_NO } reencode_mode = REENCODE_ABORT;
static int fake_missing_tagger;
static int use_done_feature;
static int no_data;
@@ -77,6 +78,31 @@ static int parse_opt_tag_of_filtered_mode(const struct option *opt,
return 0;
}
+static int parse_opt_reencode_mode(const struct option *opt,
+ const char *arg, int unset)
+{
+ if (unset) {
+ reencode_mode = REENCODE_ABORT;
+ return 0;
+ }
+
+ switch (git_parse_maybe_bool(arg)) {
+ case 0:
+ reencode_mode = REENCODE_NO;
+ break;
+ case 1:
+ reencode_mode = REENCODE_YES;
+ break;
+ default:
+ if (!strcasecmp(arg, "abort"))
+ reencode_mode = REENCODE_ABORT;
+ else
+ return error("Unknown reencoding mode: %s", arg);
+ }
+
+ return 0;
+}
+
static struct decoration idnums;
static uint32_t last_idnum;
@@ -633,10 +659,21 @@ static void handle_commit(struct commit *commit, struct rev_info *rev,
}
mark_next_object(&commit->object);
- if (anonymize)
+ if (anonymize) {
reencoded = anonymize_commit_message(message);
- else if (!is_encoding_utf8(encoding))
- reencoded = reencode_string(message, "UTF-8", encoding);
+ } else if (encoding) {
+ switch(reencode_mode) {
+ case REENCODE_YES:
+ reencoded = reencode_string(message, "UTF-8", encoding);
+ break;
+ case REENCODE_NO:
+ break;
+ case REENCODE_ABORT:
+ die("Encountered commit-specific encoding %s in commit "
+ "%s; use --reencode=[yes|no] to handle it",
+ encoding, oid_to_hex(&commit->object.oid));
+ }
+ }
if (!commit->parents)
printf("reset %s\n", refname);
printf("commit %s\nmark :%"PRIu32"\n", refname, last_idnum);
@@ -1091,6 +1128,9 @@ int cmd_fast_export(int argc, const char **argv, const char *prefix)
OPT_CALLBACK(0, "tag-of-filtered-object", &tag_of_filtered_mode, N_("mode"),
N_("select handling of tags that tag filtered objects"),
parse_opt_tag_of_filtered_mode),
+ OPT_CALLBACK(0, "reencode", &reencode_mode, N_("mode"),
+ N_("select handling of commit messages in an alternate encoding"),
+ parse_opt_reencode_mode),
OPT_STRING(0, "export-marks", &export_filename, N_("file"),
N_("Dump marks to this file")),
OPT_STRING(0, "import-marks", &import_filename, N_("file"),
diff --git a/t/t9350-fast-export.sh b/t/t9350-fast-export.sh
index e2ab8eddc0..b4004e05c2 100755
--- a/t/t9350-fast-export.sh
+++ b/t/t9350-fast-export.sh
@@ -94,14 +94,14 @@ test_expect_success 'fast-export --show-original-ids | git fast-import' '
test $MUSS = $(git rev-parse --verify refs/tags/muss)
'
-test_expect_success 'iso-8859-7' '
+test_expect_success 'reencoding iso-8859-7' '
test_when_finished "git reset --hard HEAD~1" &&
test_config i18n.commitencoding iso-8859-7 &&
test_tick &&
echo rosten >file &&
git commit -s -F "$TEST_DIRECTORY/t9350/simple-iso-8859-7-commit-message.txt" file &&
- git fast-export wer^..wer >iso-8859-7.fi &&
+ git fast-export --reencode=yes wer^..wer >iso-8859-7.fi &&
sed "s/wer/i18n/" iso-8859-7.fi |
(cd new &&
git fast-import &&
@@ -118,13 +118,45 @@ test_expect_success 'iso-8859-7' '
! grep ^encoding actual)
'
+test_expect_success 'aborting on iso-8859-7' '
+
+ test_when_finished "git reset --hard HEAD~1" &&
+ test_config i18n.commitencoding iso-8859-7 &&
+ echo rosten >file &&
+ git commit -s -F "$TEST_DIRECTORY/t9350/simple-iso-8859-7-commit-message.txt" file &&
+ test_must_fail git fast-export --reencode=abort wer^..wer >iso-8859-7.fi
+'
+
+test_expect_success 'preserving iso-8859-7' '
+
+ test_when_finished "git reset --hard HEAD~1" &&
+ test_config i18n.commitencoding iso-8859-7 &&
+ echo rosten >file &&
+ git commit -s -F "$TEST_DIRECTORY/t9350/simple-iso-8859-7-commit-message.txt" file &&
+ git fast-export --reencode=no wer^..wer >iso-8859-7.fi &&
+ sed "s/wer/i18n-no-recoding/" iso-8859-7.fi |
+ (cd new &&
+ git fast-import &&
+ # The commit object, if not re-encoded, is 240 bytes.
+ # Removing the "encoding iso-8859-7\n" header would drops 20
+ # bytes. Re-encoding the Pi character from \xF0 (\360) in
+ # iso-8859-7 to \xCF\x80 (\317\200) in UTF-8 adds a byte.
+ # Check for the expected size...
+ test 240 -eq "$(git cat-file -s i18n-no-recoding)" &&
+ # ...as well as the expected byte.
+ git cat-file commit i18n-no-recoding >actual &&
+ grep $(printf "\360") actual &&
+ # Also make sure the commit has the "encoding" header
+ grep ^encoding actual)
+'
+
test_expect_success 'encoding preserved if reencoding fails' '
test_when_finished "git reset --hard HEAD~1" &&
test_config i18n.commitencoding iso-8859-7 &&
echo rosten >file &&
git commit -s -F "$TEST_DIRECTORY/t9350/broken-iso-8859-7-commit-message.txt" file &&
- git fast-export wer^..wer >iso-8859-7.fi &&
+ git fast-export --reencode=yes wer^..wer >iso-8859-7.fi &&
sed "s/wer/i18n-invalid/" iso-8859-7.fi |
(cd new &&
git fast-import &&
--
2.21.0.782.gd18f03d1bf
