@matheusbsbs / matheus-bagliano / commits / 43966ab315

revert: optionally refer to commit in the "reference" format

A typical "git revert" commit uses the full title of the original commit in its title, and starts its body of the message with: This reverts commit 8fa7f667cf61386257c00d6e954855cc3215ae91. This does not encourage the best practice of describing not just "what" (i.e. "Revert X" on the title says what we did) but "why" (i.e. and it does not say why X was undesirable). We can instead phrase this first line of the body to be more like This reverts commit 8fa7f667 (do this and that, 2022-04-25) so that the title does not have to be Revert "do this and that" We can instead use the title to describe "why" we are reverting the original commit. Introduce the "--reference" option to "git revert", and also the revert.reference configuration variable, which defaults to false, to tweak the title and the first line of the draft commit message for when creating a "revert" commit. When this option is in use, the first line of the pre-filled editor buffer becomes a comment line that tells the user to say _why_. If the user exits the editor without touching this line by mistake, what we prepare to become the first line of the body, i.e. "This reverts commit 8fa7f667 (do this and that, 2022-04-25)", ends up to be the title of the resulting commit. This behaviour is designed to help such a user to identify such a revert in "git log --oneline" easily so that it can be further reworded with "git rebase -i" later. Signed-off-by: Junio C Hamano <gitster@pobox.com>

Junio C Hamano committed May 26, 2022 at 23:01 UTC 43966ab3156a082067bf9930351e96e9488da735

6 files changed +74 -5

Documentation/config/revert.txt new

@@ -0,0 +1,3 @@

1 +revert.reference::

2 + Setting this variable to true makes `git revert` to behave

3 + as if the `--reference` option is given.

Documentation/git-revert.txt

@@ -117,6 +117,15 @@ effect to your index in a row.

117 Allow the rerere mechanism to update the index with the

118 result of auto-conflict resolution if possible.

119

120 +--reference::

121 + Instead of starting the body of the log message with "This

122 + reverts <full object name of the commit being reverted>.",

123 + refer to the commit using "--pretty=reference" format

124 + (cf. linkgit:git-log[1]). The `revert.reference`

125 + configuration variable can be used to enable this option by

126 + default.

127 +

128 +

129 SEQUENCER SUBCOMMANDS

130 ---------------------

131 include::sequencer.txt[]

builtin/revert.c

@@ -116,6 +116,8 @@ static int run_sequencer(int argc, const char **argv, struct replay_opts *opts)

116 N_("option for merge strategy"), option_parse_x),

117 { OPTION_STRING, 'S', "gpg-sign", &opts->gpg_sign, N_("key-id"),

118 N_("GPG sign commit"), PARSE_OPT_OPTARG, NULL, (intptr_t) "" },

119 + OPT_BOOL(0, "reference", &opts->commit_use_reference,

120 + N_("use the 'reference' format to refer to commits")),

121 OPT_END()

122 };

123 struct option *options = base_options;

sequencer.c

+28 -5

@@ -221,6 +221,9 @@ static int git_sequencer_config(const char *k, const char *v, void *cb)

221 return ret;

222 }

223

224 + if (!strcmp(k, "revert.reference"))

225 + opts->commit_use_reference = git_config_bool(k, v);

226 +

227 status = git_gpg_config(k, v, NULL);

228 if (status)

229 return status;

@@ -2059,6 +2062,20 @@ static int should_edit(struct replay_opts *opts) {

2062 return opts->edit;

2063 }

2064

2065 +static void refer_to_commit(struct replay_opts *opts,

2066 + struct strbuf *msgbuf, struct commit *commit)

2067 +{

2068 + if (opts->commit_use_reference) {

2069 + struct pretty_print_context ctx = {

2070 + .abbrev = DEFAULT_ABBREV,

2071 + .date_mode.type = DATE_SHORT,

2072 + };

2073 + format_commit_message(commit, "%h (%s, %ad)", msgbuf, &ctx);

2074 + } else {

2075 + strbuf_addstr(msgbuf, oid_to_hex(&commit->object.oid));

2076 + }

2077 +}

2078 +

2079 static int do_pick_commit(struct repository *r,

2080 struct todo_item *item,

2081 struct replay_opts *opts,

@@ -2167,14 +2184,20 @@ static int do_pick_commit(struct repository *r,

2184 base_label = msg.label;

2185 next = parent;

2186 next_label = msg.parent_label;

2170 - strbuf_addstr(&msgbuf, "Revert \"");

2171 - strbuf_addstr(&msgbuf, msg.subject);

2172 - strbuf_addstr(&msgbuf, "\"\n\nThis reverts commit ");

2173 - strbuf_addstr(&msgbuf, oid_to_hex(&commit->object.oid));

2187 + if (opts->commit_use_reference) {

2188 + strbuf_addstr(&msgbuf,

2189 + "# *** SAY WHY WE ARE REVERTING ON THE TITLE LINE ***");

2190 + } else {

2191 + strbuf_addstr(&msgbuf, "Revert \"");

2192 + strbuf_addstr(&msgbuf, msg.subject);

2193 + strbuf_addstr(&msgbuf, "\"");

2194 + }

2195 + strbuf_addstr(&msgbuf, "\n\nThis reverts commit ");

2196 + refer_to_commit(opts, &msgbuf, commit);

2197

2198 if (commit->parents && commit->parents->next) {

2199 strbuf_addstr(&msgbuf, ", reversing\nchanges made to ");

2177 - strbuf_addstr(&msgbuf, oid_to_hex(&parent->object.oid));

2200 + refer_to_commit(opts, &msgbuf, parent);

2201 }

2202 strbuf_addstr(&msgbuf, ".\n");

2203 } else {

sequencer.h

@@ -49,6 +49,7 @@ struct replay_opts {

49 int reschedule_failed_exec;

50 int committer_date_is_author_date;

51 int ignore_date;

52 + int commit_use_reference;

54 int mainline;

t/t3501-revert-cherry-pick.sh

+31

@@ -159,6 +159,7 @@ test_expect_success 'cherry-pick works with dirty renamed file' '

159 '

160

161 test_expect_success 'advice from failed revert' '

162 + test_when_finished "git reset --hard" &&

163 test_commit --no-tag "add dream" dream dream &&

164 dream_oid=$(git rev-parse --short HEAD) &&

165 cat <<-EOF >expected &&

@@ -174,4 +175,34 @@ test_expect_success 'advice from failed revert' '

175 test_must_fail git revert HEAD^ 2>actual &&

176 test_cmp expected actual

177 '

178 +

179 +test_expect_success 'identification of reverted commit (default)' '

180 + test_commit to-ident &&

181 + test_when_finished "git reset --hard to-ident" &&

182 + git checkout --detach to-ident &&

183 + git revert --no-edit HEAD &&

184 + git cat-file commit HEAD >actual.raw &&

185 + grep "^This reverts " actual.raw >actual &&

186 + echo "This reverts commit $(git rev-parse HEAD^)." >expect &&

187 + test_cmp expect actual

188 +'

189 +

190 +test_expect_success 'identification of reverted commit (--reference)' '

191 + git checkout --detach to-ident &&

192 + git revert --reference --no-edit HEAD &&

193 + git cat-file commit HEAD >actual.raw &&

194 + grep "^This reverts " actual.raw >actual &&

195 + echo "This reverts commit $(git show -s --pretty=reference HEAD^)." >expect &&

196 + test_cmp expect actual

197 +'

198 +

199 +test_expect_success 'identification of reverted commit (revert.reference)' '

200 + git checkout --detach to-ident &&

201 + git -c revert.reference=true revert --no-edit HEAD &&

202 + git cat-file commit HEAD >actual.raw &&

203 + grep "^This reverts " actual.raw >actual &&

204 + echo "This reverts commit $(git show -s --pretty=reference HEAD^)." >expect &&

205 + test_cmp expect actual

206 +'

207 +

208 test_done