[PATCH 3/3] fast-export: allow dumping the path mapping
- From
Jeff King <peff@peff.net>
- Date
- Jun 19, 2020, 13:29 UTC
- Message-ID
- <20200619132923.GA2540897@coredump.intra.peff.net>
- In-Reply-To
- <20200619132304.GA2540657@coredump.intra.peff.net>
When working with an anonymized repo, it can be useful to be able to refer to particular paths. E.g., reproducing a bug with "git rev-list -- foo.c" in the original repo would need to replace "foo.c" with its anonymized counterpart to produce the same effect.
We recently taught fast-export to dump the refname mapping. Let's do the same thing for paths, which can reuse most of the same infrastructure. Note that the output format isn't unambiguous here (because paths could contain spaces). That's OK because this is meant to be examined by a human.
We could also just introduce a "dump mapping" file that shows every mapping we make. But it would be a bit more awkward to work with, as the user would have to sort through more data to find the parts they're interested in (and there are likely to be many more paths than refnames, making it annoying for people who just want to dump the refnames).
Signed-off-by: Jeff King <peff@peff.net> --- Documentation/git-fast-export.txt | 10 ++++++++++ builtin/fast-export.c | 12 ++++++++++++ t/t9351-fast-export-anonymize.sh | 8 ++++++++ 3 files changed, 30 insertions(+)
diff --git a/Documentation/git-fast-export.txt b/Documentation/git-fast-export.txt index e809bb3f18..c63f109f1d 100644 --- a/Documentation/git-fast-export.txt +++ b/Documentation/git-fast-export.txt @@ -125,6 +125,12 @@ by keeping the marks the same across runs. the output stream, with the original refname, a space, and its anonymized counterpart. See the section on `ANONYMIZING` below. +--dump-anonymized-paths=<file>:: + Output the mapping of real paths to anonymized paths to <file>. + The output will contain one line per path that appears in the + output stream, with the original path, a space, and its + anonymized counterpart. See the section on `ANONYMIZING` below. + --reference-excluded-parents:: By default, running a command such as `git fast-export master~5..master` will not include the commit master{tilde}5 @@ -261,6 +267,10 @@ refs/tags/v2.0 refs/tags/ref50 which tells you that `git rev-list ref31..ref50` may produce the same bug in the re-imported anonymous repository. +Likewise, `--dump-anonymized-paths` may be useful for a bug that +involves pathspecs. E.g., `git rev-list v1.0..v2.0 -- foo.c` requires +knowing the path corresponding to `foo.c` in the result. + LIMITATIONS ----------- diff --git a/builtin/fast-export.c b/builtin/fast-export.c index cd0174d514..ed1f8daa7f 100644 --- a/builtin/fast-export.c +++ b/builtin/fast-export.c @@ -47,6 +47,7 @@ static struct string_list tag_refs = STRING_LIST_INIT_NODUP; static struct refspec refspecs = REFSPEC_INIT_FETCH; static int anonymize; static FILE *anonymized_refnames_handle; +static FILE *anonymized_paths_handle; static struct revision_sources revision_sources; static int parse_opt_signed_tag_mode(const struct option *opt, @@ -211,6 +212,9 @@ static void anonymize_path(struct strbuf *out, const char *path, struct hashmap *map, void *(*generate)(const void *, size_t *)) { + static struct seen_set seen; + const char *full_path = path; + while (*path) { const char *end_of_component = strchrnul(path, '/'); size_t len = end_of_component - path; @@ -220,6 +224,8 @@ static void anonymize_path(struct strbuf *out, const char *path, if (*path) strbuf_addch(out, *path++); } + + maybe_dump_anon(anonymized_paths_handle, &seen, full_path, out->buf); } static inline void *mark_to_ptr(uint32_t mark) @@ -1170,6 +1176,7 @@ int cmd_fast_export(int argc, const char **argv, const char *prefix) *import_filename = NULL, *import_filename_if_exists = NULL; const char *anonymized_refnames_file = NULL; + const char *anonymized_paths_file = NULL; uint32_t lastimportid; struct string_list refspecs_list = STRING_LIST_INIT_NODUP; struct string_list paths_of_changed_objects = STRING_LIST_INIT_DUP; @@ -1206,6 +1213,9 @@ int cmd_fast_export(int argc, const char **argv, const char *prefix) OPT_STRING(0, "dump-anonymized-refnames", &anonymized_refnames_file, N_("file"), N_("output anonymized refname mapping to <file>")), + OPT_STRING(0, "dump-anonymized-paths", + &anonymized_paths_file, N_("file"), + N_("output anonymized path mapping to <file>")), OPT_BOOL(0, "reference-excluded-parents", &reference_excluded_commits, N_("Reference parents which are not in fast-export stream by object id")), OPT_BOOL(0, "show-original-ids", &show_original_ids, @@ -1244,6 +1254,8 @@ int cmd_fast_export(int argc, const char **argv, const char *prefix) if (anonymized_refnames_file) anonymized_refnames_handle = xfopen(anonymized_refnames_file, "w"); + if (anonymized_paths_file) + anonymized_paths_handle = xfopen(anonymized_paths_file, "w"); if (use_done_feature) printf("feature done\n"); diff --git a/t/t9351-fast-export-anonymize.sh b/t/t9351-fast-export-anonymize.sh index 88847b0f60..3607b9b972 100755 --- a/t/t9351-fast-export-anonymize.sh +++ b/t/t9351-fast-export-anonymize.sh @@ -53,6 +53,14 @@ test_expect_success 'refname mapping can be dumped' ' grep "^refs/heads/other refs/heads/" refs.out ' +test_expect_success 'path mapping can be dumped' ' + git fast-export --anonymize --all \ + --dump-anonymized-paths=paths.out >/dev/null && + # do not assume a particular anonymization scheme or order; + # just sanity check that a sample line looks sensible. + grep "^foo " paths.out +' + # NOTE: we chdir to the new, anonymized repository # after this. All further tests should assume this. test_expect_success 'import stream to new repository' '
-- 2.27.0.480.g4f98dbcb10