| Message ID | 20241118151755.756265-6-bence@ferdinandy.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | set-head/fetch remote/HEAD updates | expand |
Bence Ferdinandy <bence@ferdinandy.com> writes: > +static void report_set_head_auto(const char *remote, const char *head_name, > + struct strbuf *b_local_head, int updateres) { "updateres" was too mysterious a name. "res" stands for what, "resource"? Looking at the way the parameter is used by the code, it seems to indicate that the remote HEAD originally was in a detached state, so "was_detached" may be a better name, perhaps? > + else if (!!updateres && b_local_head->len) > + printf(_("'%s/HEAD' was detached at '%s' and now points to '%s'\n"), > + remote, b_local_head->buf, head_name); There is no need for !!; any non-zero integer is true. !! is useful only in a context that takes only 0 and 1 (like when you are making an assignment to a variable or a structure member that takes only 0 or 1). > static int set_head(int argc, const char **argv, const char *prefix) > { > - int i, opt_a = 0, opt_d = 0, result = 0; > - struct strbuf b_head = STRBUF_INIT, b_remote_head = STRBUF_INIT; > + int i, opt_a = 0, opt_d = 0, result = 0, updateres; > + struct strbuf b_head = STRBUF_INIT, b_remote_head = STRBUF_INIT, > + b_local_head = STRBUF_INIT; > @@ -1440,20 +1468,27 @@ static int set_head(int argc, const char **argv, const char *prefix) > } else > usage_with_options(builtin_remote_sethead_usage, options); > > - if (head_name) { > - strbuf_addf(&b_remote_head, "refs/remotes/%s/%s", argv[0], head_name); > - /* make sure it's valid */ > - if (!refs_ref_exists(refs, b_remote_head.buf)) > - result |= error(_("Not a valid ref: %s"), b_remote_head.buf); > - else if (refs_update_symref(refs, b_head.buf, b_remote_head.buf, "remote set-head")) > - result |= error(_("Could not setup %s"), b_head.buf); > - else if (opt_a) > - printf("%s/HEAD set to %s\n", argv[0], head_name); > - free(head_name); > + if (!head_name) > + goto cleanup; > + strbuf_addf(&b_remote_head, "refs/remotes/%s/%s", argv[0], head_name); > + if (!refs_ref_exists(refs, b_remote_head.buf)) { > + result |= error(_("Not a valid ref: %s"), b_remote_head.buf); > + goto cleanup; > + } OK, we refuse to allow a manual "remote set-head" to create a dangling symref, which is a faithful rewrite from the original. > + updateres = refs_update_symref_extended(refs, b_head.buf, b_remote_head.buf, > + "remote set-head", &b_local_head); > + if (updateres == -2) { Where does this -2 come from? It is not the "you asked to read it as a symref but it wasn't a symref" thing, which was mapped to -1 with [PATCH 3/9]. It is an unusual way to construct an extensible API function to say "all different kinds of errors we happen to know when this particular caller was written return -2, but some special cases are not -2". Rather, "all negatives, other than these selected few values we special-case and handle, are errors" is more natural, isn't it? Maybe I am misreading the code and missing where the -2 comes from or the significance of the value? I dunno.
On Tue Nov 19, 2024 at 03:27, Junio C Hamano <gitster@pobox.com> wrote: > Bence Ferdinandy <bence@ferdinandy.com> writes: > >> +static void report_set_head_auto(const char *remote, const char *head_name, >> + struct strbuf *b_local_head, int updateres) { > > "updateres" was too mysterious a name. "res" stands for what, > "resource"? > > Looking at the way the parameter is used by the code, it seems to > indicate that the remote HEAD originally was in a detached state, so > "was_detached" may be a better name, perhaps? "res" wanted to be short for result, but "was_detached" is definitely more readable. > >> + else if (!!updateres && b_local_head->len) >> + printf(_("'%s/HEAD' was detached at '%s' and now points to '%s'\n"), >> + remote, b_local_head->buf, head_name); > > There is no need for !!; any non-zero integer is true. !! is useful > only in a context that takes only 0 and 1 (like when you are making > an assignment to a variable or a structure member that takes only 0 > or 1). > >> static int set_head(int argc, const char **argv, const char *prefix) >> { >> - int i, opt_a = 0, opt_d = 0, result = 0; >> - struct strbuf b_head = STRBUF_INIT, b_remote_head = STRBUF_INIT; >> + int i, opt_a = 0, opt_d = 0, result = 0, updateres; >> + struct strbuf b_head = STRBUF_INIT, b_remote_head = STRBUF_INIT, >> + b_local_head = STRBUF_INIT; > >> @@ -1440,20 +1468,27 @@ static int set_head(int argc, const char **argv, const char *prefix) >> } else >> usage_with_options(builtin_remote_sethead_usage, options); >> >> - if (head_name) { >> - strbuf_addf(&b_remote_head, "refs/remotes/%s/%s", argv[0], head_name); >> - /* make sure it's valid */ >> - if (!refs_ref_exists(refs, b_remote_head.buf)) >> - result |= error(_("Not a valid ref: %s"), b_remote_head.buf); >> - else if (refs_update_symref(refs, b_head.buf, b_remote_head.buf, "remote set-head")) >> - result |= error(_("Could not setup %s"), b_head.buf); >> - else if (opt_a) >> - printf("%s/HEAD set to %s\n", argv[0], head_name); >> - free(head_name); >> + if (!head_name) >> + goto cleanup; >> + strbuf_addf(&b_remote_head, "refs/remotes/%s/%s", argv[0], head_name); >> + if (!refs_ref_exists(refs, b_remote_head.buf)) { >> + result |= error(_("Not a valid ref: %s"), b_remote_head.buf); >> + goto cleanup; >> + } > > OK, we refuse to allow a manual "remote set-head" to create a > dangling symref, which is a faithful rewrite from the original. > >> + updateres = refs_update_symref_extended(refs, b_head.buf, b_remote_head.buf, >> + "remote set-head", &b_local_head); > >> + if (updateres == -2) { > > Where does this -2 come from? It is not the "you asked to read it > as a symref but it wasn't a symref" thing, which was mapped to -1 > with [PATCH 3/9]. No, it is not, but it's also a mistake. It should be `updateres == 1`. refs_update_symref_extended outputs -1 for "not a symref" and 1 for any other error currently. Before I touched the code it was 1 for any error, so I left that as is. So we want to error out on set_head if we get a 1 and continue if we get 0 or -1 (and handle the difference in the report_set_head_auto). Thanks for noticing, I'll get that fixed in v14.
"Bence Ferdinandy" <bence@ferdinandy.com> writes: > No, it is not, but it's also a mistake. It should be `updateres == 1`. > refs_update_symref_extended outputs -1 for "not a symref" and 1 for any other > error currently. Before I touched the code it was 1 for any error, so I left > that as is. So we want to error out on set_head if we get a 1 and continue if > we get 0 or -1 (and handle the difference in the report_set_head_auto). > > Thanks for noticing, I'll get that fixed in v14. It is good that somebody noticed it (and it may have happened to be me), but if it is a "mistake" as you said, I wonder why none of your tests caught it. Do we have a gap in test coverage? Thanks.
On Tue Nov 19, 2024 at 11:54, Junio C Hamano <gitster@pobox.com> wrote: > "Bence Ferdinandy" <bence@ferdinandy.com> writes: > >> No, it is not, but it's also a mistake. It should be `updateres == 1`. >> refs_update_symref_extended outputs -1 for "not a symref" and 1 for any other >> error currently. Before I touched the code it was 1 for any error, so I left >> that as is. So we want to error out on set_head if we get a 1 and continue if >> we get 0 or -1 (and handle the difference in the report_set_head_auto). >> >> Thanks for noticing, I'll get that fixed in v14. > > It is good that somebody noticed it (and it may have happened to be > me), but if it is a "mistake" as you said, I wonder why none of your > tests caught it. Do we have a gap in test coverage? I think there is no test that is testing this branch: updateres = refs_update_symref_extended(refs, b_head.buf, b_remote_head.buf, "remote set-head", &b_local_head, 0); if (updateres == 1) { result |= error(_("Could not setup %s"), b_head.buf); goto cleanup; Running this in t/ grep -r "Could not setup" also yield nothing, so that's probably true. I'm wondering what would be the best way to trigger this error, refs_update_symref needs to fail for this.
diff --git a/builtin/remote.c b/builtin/remote.c index 1d68c5b2ba..a682ef5df2 100644 --- a/builtin/remote.c +++ b/builtin/remote.c @@ -1399,10 +1399,38 @@ static int show(int argc, const char **argv, const char *prefix) return result; } +static void report_set_head_auto(const char *remote, const char *head_name, + struct strbuf *b_local_head, int updateres) { + struct strbuf buf_prefix = STRBUF_INIT; + const char *prev_head = NULL; + + strbuf_addf(&buf_prefix, "refs/remotes/%s/", remote); + skip_prefix(b_local_head->buf, buf_prefix.buf, &prev_head); + + if (prev_head && !strcmp(prev_head, head_name)) + printf(_("'%s/HEAD' is unchanged and points to '%s'\n"), + remote, head_name); + else if (prev_head) + printf(_("'%s/HEAD' has changed from '%s' and now points to '%s'\n"), + remote, prev_head, head_name); + else if (!b_local_head->len) + printf(_("'%s/HEAD' is now created and points to '%s'\n"), + remote, head_name); + else if (!!updateres && b_local_head->len) + printf(_("'%s/HEAD' was detached at '%s' and now points to '%s'\n"), + remote, b_local_head->buf, head_name); + else + printf(_("'%s/HEAD' used to point to '%s' " + "(which is not a remote branch), but now points to '%s'\n"), + remote, b_local_head->buf, head_name); + strbuf_release(&buf_prefix); +} + static int set_head(int argc, const char **argv, const char *prefix) { - int i, opt_a = 0, opt_d = 0, result = 0; - struct strbuf b_head = STRBUF_INIT, b_remote_head = STRBUF_INIT; + int i, opt_a = 0, opt_d = 0, result = 0, updateres; + struct strbuf b_head = STRBUF_INIT, b_remote_head = STRBUF_INIT, + b_local_head = STRBUF_INIT; char *head_name = NULL; struct ref_store *refs = get_main_ref_store(the_repository); @@ -1440,20 +1468,27 @@ static int set_head(int argc, const char **argv, const char *prefix) } else usage_with_options(builtin_remote_sethead_usage, options); - if (head_name) { - strbuf_addf(&b_remote_head, "refs/remotes/%s/%s", argv[0], head_name); - /* make sure it's valid */ - if (!refs_ref_exists(refs, b_remote_head.buf)) - result |= error(_("Not a valid ref: %s"), b_remote_head.buf); - else if (refs_update_symref(refs, b_head.buf, b_remote_head.buf, "remote set-head")) - result |= error(_("Could not setup %s"), b_head.buf); - else if (opt_a) - printf("%s/HEAD set to %s\n", argv[0], head_name); - free(head_name); + if (!head_name) + goto cleanup; + strbuf_addf(&b_remote_head, "refs/remotes/%s/%s", argv[0], head_name); + if (!refs_ref_exists(refs, b_remote_head.buf)) { + result |= error(_("Not a valid ref: %s"), b_remote_head.buf); + goto cleanup; + } + updateres = refs_update_symref_extended(refs, b_head.buf, b_remote_head.buf, + "remote set-head", &b_local_head); + if (updateres == -2) { + result |= error(_("Could not setup %s"), b_head.buf); + goto cleanup; } + if (opt_a) + report_set_head_auto(argv[0], head_name, &b_local_head, updateres); +cleanup: + free(head_name); strbuf_release(&b_head); strbuf_release(&b_remote_head); + strbuf_release(&b_local_head); return result; } diff --git a/t/t5505-remote.sh b/t/t5505-remote.sh index 9b50276646..807df00ba7 100755 --- a/t/t5505-remote.sh +++ b/t/t5505-remote.sh @@ -432,12 +432,63 @@ test_expect_success 'set-head --auto' ' ) ' +test_expect_success 'set-head --auto detects creation' ' + ( + cd test && + git update-ref --no-deref -d refs/remotes/origin/HEAD && + git remote set-head --auto origin >output && + echo "${SQ}origin/HEAD${SQ} is now created and points to ${SQ}main${SQ}" >expect && + test_cmp expect output + ) +' + +test_expect_success 'set-head --auto to update a non symbolic ref' ' + ( + cd test && + git update-ref --no-deref -d refs/remotes/origin/HEAD && + git update-ref refs/remotes/origin/HEAD HEAD && + HEAD=$(git log --pretty="%H") && + git remote set-head --auto origin >output && + echo "${SQ}origin/HEAD${SQ} was detached at ${SQ}${HEAD}${SQ} and now points to ${SQ}main${SQ}" >expect && + test_cmp expect output + ) +' + +test_expect_success 'set-head --auto detects no change' ' + ( + cd test && + git remote set-head --auto origin >output && + echo "${SQ}origin/HEAD${SQ} is unchanged and points to ${SQ}main${SQ}" >expect && + test_cmp expect output + ) +' + +test_expect_success 'set-head --auto detects change' ' + ( + cd test && + git symbolic-ref refs/remotes/origin/HEAD refs/remotes/origin/ahead && + git remote set-head --auto origin >output && + echo "${SQ}origin/HEAD${SQ} has changed from ${SQ}ahead${SQ} and now points to ${SQ}main${SQ}" >expect && + test_cmp expect output + ) +' + +test_expect_success 'set-head --auto detects strange ref' ' + ( + cd test && + git symbolic-ref refs/remotes/origin/HEAD refs/heads/main && + git remote set-head --auto origin >output && + echo "${SQ}origin/HEAD${SQ} used to point to ${SQ}refs/heads/main${SQ} (which is not a remote branch), but now points to ${SQ}main${SQ}" >expect && + test_cmp expect output + ) +' + test_expect_success 'set-head --auto has no problem w/multiple HEADs' ' ( cd test && git fetch two "refs/heads/*:refs/remotes/two/*" && git remote set-head --auto two >output 2>&1 && - echo "two/HEAD set to main" >expect && + echo "${SQ}two/HEAD${SQ} is now created and points to ${SQ}main${SQ}" >expect && test_cmp expect output ) ' @@ -456,6 +507,16 @@ test_expect_success 'set-head explicit' ' ) ' +test_expect_success 'set-head --auto reports change' ' + ( + cd test && + git remote set-head origin side2 && + git remote set-head --auto origin >output 2>&1 && + echo "${SQ}origin/HEAD${SQ} has changed from ${SQ}side2${SQ} and now points to ${SQ}main${SQ}" >expect && + test_cmp expect output + ) +' + cat >test/expect <<EOF Pruning origin URL: $(pwd)/one
Currently, set-head --auto will print a message saying "remote/HEAD set to branch", which implies something was changed. Change the output of --auto, so the output actually reflects what was done: a) set a previously unset HEAD, b) change HEAD because remote changed or c) no updates. As edge cases, if HEAD is changed from a previous symbolic reference that was not a remote branch, explicitly call attention to this fact, and also notify the user if the previous reference was not a symbolic reference. Signed-off-by: Bence Ferdinandy <bence@ferdinandy.com> --- Notes: v1-v2: was RFC in https://lore.kernel.org/git/20240910203835.2288291-1-bence@ferdinandy.com/ v3: This patch was originally sent along when I thought set-head was going to be invoked by fetch, but the discussion on the RFC concluded that it should be not. This opened the possibility to make it more explicit. Note: although I feel both things the patch does are really just cosmetic, an argument could be made for breaking it into two, one for the no-op part and one for the --auto print update. Was sent in: https://lore.kernel.org/git/20240915221055.904107-1-bence@ferdinandy.com/ v4: - changes are now handled atomically via the ref update transaction - outputs have changed along the lines of Junio's suggestion - minor refactor to set_head for improved legibility v5: - the minor refactor has been split out into its own patch v6: - fixed uninitialized prev_head - fixed case of unusual previous target - fixed a test that would have been actually broken at this patch (the output was only correct with the later update to fetch) - added 4 tests for the 4 output cases v7: - change commit prefix to be more in line with project standards - fixed tests to also work with the reftable backend - renamed report function, fixed style issue with checking buf len - fixed not releasing an strbuf v8: no change v9: - mark output strings in report_set_head_auto as translatable - rename buf_prev to b_local_head for consistency - use ${SQ} in tests instead of '\'' v10: no change v11: no change v12: no change v13: added handling the edge case of previous remote/HEAD being a detached HEAD builtin/remote.c | 59 +++++++++++++++++++++++++++++++++++--------- t/t5505-remote.sh | 63 ++++++++++++++++++++++++++++++++++++++++++++++- 2 files changed, 109 insertions(+), 13 deletions(-)