git/advice.c
Christopher Tiwald f25950f347 push: Provide situational hints for non-fast-forward errors
Pushing a non-fast-forward update to a remote repository will result in
an error, but the hint text doesn't provide the correct resolution in
every case. Give better resolution advice in three push scenarios:

1) If you push your current branch and it triggers a non-fast-forward
error, you should merge remote changes with 'git pull' before pushing
again.

2) If you push to a shared repository others push to, and your local
tracking branches are not kept up to date, the 'matching refs' default
will generate non-fast-forward errors on outdated branches. If this is
your workflow, the 'matching refs' default is not for you. Consider
setting the 'push.default' configuration variable to 'current' or
'upstream' to ensure only your current branch is pushed.

3) If you explicitly specify a ref that is not your current branch or
push matching branches with ':', you will generate a non-fast-forward
error if any pushed branch tip is out of date. You should checkout the
offending branch and merge remote changes before pushing again.

Teach transport.c to recognize these scenarios and configure push.c
to hint for them. If 'git push's default behavior changes or we
discover more scenarios, extension is easy. Standardize on the
advice API and add three new advice variables, 'pushNonFFCurrent',
'pushNonFFDefault', and 'pushNonFFMatching'. Setting any of these
to 'false' will disable their affiliated advice. Setting
'pushNonFastForward' to false will disable all three, thus preserving the
config option for users who already set it, but guaranteeing new
users won't disable push advice accidentally.

Based-on-patch-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Christopher Tiwald <christiwald@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-03-19 21:42:06 -07:00

96 lines
2.6 KiB
C

#include "cache.h"
int advice_push_nonfastforward = 1;
int advice_push_non_ff_current = 1;
int advice_push_non_ff_default = 1;
int advice_push_non_ff_matching = 1;
int advice_status_hints = 1;
int advice_commit_before_merge = 1;
int advice_resolve_conflict = 1;
int advice_implicit_identity = 1;
int advice_detached_head = 1;
static struct {
const char *name;
int *preference;
} advice_config[] = {
{ "pushnonfastforward", &advice_push_nonfastforward },
{ "pushnonffcurrent", &advice_push_non_ff_current },
{ "pushnonffdefault", &advice_push_non_ff_default },
{ "pushnonffmatching", &advice_push_non_ff_matching },
{ "statushints", &advice_status_hints },
{ "commitbeforemerge", &advice_commit_before_merge },
{ "resolveconflict", &advice_resolve_conflict },
{ "implicitidentity", &advice_implicit_identity },
{ "detachedhead", &advice_detached_head },
};
void advise(const char *advice, ...)
{
struct strbuf buf = STRBUF_INIT;
va_list params;
const char *cp, *np;
va_start(params, advice);
strbuf_addf(&buf, advice, params);
va_end(params);
for (cp = buf.buf; *cp; cp = np) {
np = strchrnul(cp, '\n');
fprintf(stderr, _("hint: %.*s\n"), (int)(np - cp), cp);
if (*np)
np++;
}
strbuf_release(&buf);
}
int git_default_advice_config(const char *var, const char *value)
{
const char *k = skip_prefix(var, "advice.");
int i;
for (i = 0; i < ARRAY_SIZE(advice_config); i++) {
if (strcmp(k, advice_config[i].name))
continue;
*advice_config[i].preference = git_config_bool(var, value);
return 0;
}
return 0;
}
int error_resolve_conflict(const char *me)
{
error("'%s' is not possible because you have unmerged files.", me);
if (advice_resolve_conflict)
/*
* Message used both when 'git commit' fails and when
* other commands doing a merge do.
*/
advise(_("Fix them up in the work tree,\n"
"and then use 'git add/rm <file>' as\n"
"appropriate to mark resolution and make a commit,\n"
"or use 'git commit -a'."));
return -1;
}
void NORETURN die_resolve_conflict(const char *me)
{
error_resolve_conflict(me);
die("Exiting because of an unresolved conflict.");
}
void detach_advice(const char *new_name)
{
const char fmt[] =
"Note: checking out '%s'.\n\n"
"You are in 'detached HEAD' state. You can look around, make experimental\n"
"changes and commit them, and you can discard any commits you make in this\n"
"state without impacting any branches by performing another checkout.\n\n"
"If you want to create a new branch to retain commits you create, you may\n"
"do so (now or later) by using -b with the checkout command again. Example:\n\n"
" git checkout -b new_branch_name\n\n";
fprintf(stderr, fmt, new_name);
}