From e80001f8fd7f608c6d05ce0ab2ebfc90d724a307 Mon Sep 17 00:00:00 2001 From: Elijah Newren Date: Mon, 13 May 2019 21:31:02 -0700 Subject: [PATCH] fast-export: do automatic reencoding of commit messages only if requested 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 Signed-off-by: Junio C Hamano --- 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 && -- 2.11.4.GIT