commit f52e24d844b8acbff9e1322c3f5e2507d9cd4b5f
from: "Lorenz (xha)" <me@xha.li>
via: Thomas Adam <thomas@xteddy.org>
date: Sat Oct 28 11:32:53 2023 UTC

simplify usage of the 'mesg' histedit script command

The 'mesg' script command now requires a commit ID as its argument,
rather than being tied to a preceding 'pick' or 'edit' command.

The old model was too confusing for new users, in particular for people
used to Git's rebase -i squash semantics.
The 'mesg' command is now semantically equivalent to the 'pick' command
and additionally opens the log message in an editor.

The new syntax is simpler to use but also requires that we drop support
for one-line log messages inside the histedit script, with a commit ID
taking its place in the argument space. We don't believe this feature was
used much, and that a simplified usage model is more beneficial overall.

Patch by Lorenz (xha)
ok jamsek

commit - a80c83ad3e4a8f4b5cc64106e5b128e667e0e06c
commit + f52e24d844b8acbff9e1322c3f5e2507d9cd4b5f
blob - 52eeeda8df9fb52a8581faa28c2d29c19ca5a2be
blob + a9022d1c86abb43b679a59fe1de9fbc121bbd0e6
--- got/got.1
+++ got/got.1
@@ -3016,18 +3016,8 @@ Regular editing of history must eventually be resumed 
 .It Cm fold Ar commit Ta Combine the specified commit with the next commit
 listed further below that will be used.
 .It Cm drop Ar commit Ta Remove this commit from the edited history.
-.It Cm mesg Oo Ar log-message Oc Ta Create a new log message for the commit of
-a preceding
-.Cm pick
-or
-.Cm edit
-command on the previous line of the histedit script.
-The optional
-.Ar log-message
-argument provides a new single-line log message to use.
-If the
-.Ar log-message
-argument is omitted, open an editor where a new log message can be written.
+.It Cm mesg Ar commit Ta Open an editor to create a new log message for this
+commit.
 .El
 .Pp
 Every commit in the history being edited must be mentioned in the script.
blob - b44e7c50a8734b0886b2b7b9f3132fd713250738
blob + 802320b0b95a53b2c163b2e107f19f76d99309cd
--- got/got.c
+++ got/got.c
@@ -11695,8 +11695,7 @@ static const struct got_histedit_cmd {
 	{ GOT_HISTEDIT_FOLD, "fold", "combine with next commit that will "
 	    "be used" },
 	{ GOT_HISTEDIT_DROP, "drop", "remove commit from history" },
-	{ GOT_HISTEDIT_MESG, "mesg",
-	    "single-line log message for commit above (open editor if empty)" },
+	{ GOT_HISTEDIT_MESG, "mesg", "open editor to edit the log message" },
 };
 
 struct got_histedit_list_entry {
@@ -11759,16 +11758,11 @@ histedit_write_commit_list(struct got_object_id_queue 
 			histedit_cmd = "edit";
 		else if (fold_only && STAILQ_NEXT(qid, entry) != NULL)
 			histedit_cmd = "fold";
+		else if (edit_logmsg_only)
+			histedit_cmd = "mesg";
 		err = histedit_write_commit(&qid->id, histedit_cmd, f, repo);
 		if (err)
 			break;
-		if (edit_logmsg_only) {
-			int n = fprintf(f, "%c\n", GOT_HISTEDIT_MESG);
-			if (n < 0) {
-				err = got_ferror(f, GOT_ERR_IO);
-				break;
-			}
-		}
 	}
 
 	return err;
@@ -11985,7 +11979,7 @@ histedit_parse_list(struct got_histedit_list *histedit
 	char *line = NULL, *p, *end;
 	size_t i, linesize = 0;
 	ssize_t linelen;
-	int lineno = 0, lastcmd = -1;
+	int lineno = 0;
 	const struct got_histedit_cmd *cmd;
 	struct got_object_id *commit_id = NULL;
 	struct got_histedit_list_entry *hle = NULL;
@@ -12025,37 +12019,15 @@ histedit_parse_list(struct got_histedit_list *histedit
 		}
 		while (isspace((unsigned char)p[0]))
 			p++;
-		if (cmd->code == GOT_HISTEDIT_MESG) {
-			if (lastcmd != GOT_HISTEDIT_PICK &&
-			    lastcmd != GOT_HISTEDIT_EDIT) {
-				err = got_error(GOT_ERR_HISTEDIT_CMD);
-				break;
-			}
-			if (p[0] == '\0') {
-				err = histedit_edit_logmsg(hle, repo);
-				if (err)
-					break;
-			} else {
-				hle->logmsg = strdup(p);
-				if (hle->logmsg == NULL) {
-					err = got_error_from_errno("strdup");
-					break;
-				}
-			}
-			lastcmd = cmd->code;
-			continue;
-		} else {
-			end = p;
-			while (end[0] && !isspace((unsigned char)end[0]))
-				end++;
-			*end = '\0';
-
-			err = got_object_resolve_id_str(&commit_id, repo, p);
-			if (err) {
-				/* override error code */
-				err = histedit_syntax_error(lineno);
-				break;
-			}
+		end = p;
+		while (end[0] && !isspace((unsigned char)end[0]))
+			end++;
+		*end = '\0';
+		err = got_object_resolve_id_str(&commit_id, repo, p);
+		if (err) {
+			/* override error code */
+			err = histedit_syntax_error(lineno);
+			break;
 		}
 		hle = malloc(sizeof(*hle));
 		if (hle == NULL) {
@@ -12067,7 +12039,6 @@ histedit_parse_list(struct got_histedit_list *histedit
 		hle->logmsg = NULL;
 		commit_id = NULL;
 		TAILQ_INSERT_TAIL(histedit_cmds, hle, entry);
-		lastcmd = cmd->code;
 	}
 
 	free(line);
@@ -12269,15 +12240,6 @@ histedit_save_list(struct got_histedit_list *histedit_
 		    repo);
 		if (err)
 			break;
-
-		if (hle->logmsg) {
-			int n = fprintf(f, "%c %s\n",
-			    GOT_HISTEDIT_MESG, hle->logmsg);
-			if (n < 0) {
-				err = got_ferror(f, GOT_ERR_IO);
-				break;
-			}
-		}
 	}
 done:
 	if (f && fclose(f) == EOF && err == NULL)
@@ -12415,6 +12377,7 @@ show_histedit_progress(struct got_commit_object *commi
 	switch (hle->cmd->code) {
 	case GOT_HISTEDIT_PICK:
 	case GOT_HISTEDIT_EDIT:
+	case GOT_HISTEDIT_MESG:
 		printf("%s -> %s: %s\n", old_id_str,
 		    new_id_str ? new_id_str : "no-op change", logmsg);
 		break;
@@ -13035,7 +12998,6 @@ cmd_histedit(int argc, char *argv[])
 				goto done;
 			continue;
 		}
-
 		error = got_object_open_as_commit(&commit, repo,
 		    hle->commit_id);
 		if (error)
@@ -13076,13 +13038,15 @@ cmd_histedit(int argc, char *argv[])
 			error = got_worktree_histedit_postpone(worktree,
 			    fileindex);
 			goto done;
-		}
-
-		if (hle->cmd->code == GOT_HISTEDIT_FOLD) {
+		} else if (hle->cmd->code == GOT_HISTEDIT_FOLD) {
 			error = histedit_skip_commit(hle, worktree, repo);
 			if (error)
 				goto done;
 			continue;
+		} else if (hle->cmd->code == GOT_HISTEDIT_MESG) {
+			error = histedit_edit_logmsg(hle, repo);
+			if (error)
+				goto done;
 		}
 
 		error = histedit_commit(&merged_paths, worktree, fileindex,
blob - a8c20c791a546fc257c69e471cb4ff9e59cd4d66
blob + 4540f35d9804387c36072d1da2829b2c460a5171
--- regress/cmdline/histedit.sh
+++ regress/cmdline/histedit.sh
@@ -490,14 +490,23 @@ test_histedit_fold() {
 		test_done "$testroot" "$ret"
 		return 1
 	fi
+
+	cat > $testroot/editor.sh <<EOF
+#!/bin/sh
+ed -s "\$1" <<-EOF
+	,s/.*/committing folded changes/
+	w
+	EOF
+EOF
+	chmod +x $testroot/editor.sh
 
 	echo "fold $old_commit1" > $testroot/histedit-script
 	echo "drop $old_commit2" >> $testroot/histedit-script
 	echo "pick $old_commit3" >> $testroot/histedit-script
-	echo "mesg committing folded changes" >> $testroot/histedit-script
 
-	(cd $testroot/wt && got histedit -F $testroot/histedit-script \
-		> $testroot/stdout)
+	(cd $testroot/wt && env EDITOR="$testroot/editor.sh" \
+		VISUAL="$testroot/editor.sh" \
+		got histedit -F $testroot/histedit-script > $testroot/stdout)
 
 	local new_commit1=`git_show_parent_commit $testroot/repo`
 	local new_commit2=`git_show_head $testroot/repo`
@@ -603,7 +612,6 @@ test_histedit_edit() {
 	fi
 
 	echo "edit $old_commit1" > $testroot/histedit-script
-	echo "mesg committing changes" >> $testroot/histedit-script
 	echo "pick $old_commit2" >> $testroot/histedit-script
 
 	(cd $testroot/wt && got histedit -F $testroot/histedit-script \
@@ -650,8 +658,20 @@ test_histedit_edit() {
 	fi
 
 	(cd $testroot/wt && got unstage alpha > /dev/null)
-	(cd $testroot/wt && got histedit -c > $testroot/stdout)
 
+	cat > $testroot/editor.sh <<EOF
+#!/bin/sh
+ed -s "\$1" <<-EOF
+	,s/.*/committing changes/
+	w
+	EOF
+EOF
+	chmod +x $testroot/editor.sh
+
+	(cd $testroot/wt && env EDITOR="$testroot/editor.sh" \
+		VISUAL="$testroot/editor.sh" \
+		got histedit -c > $testroot/stdout)
+
 	local new_commit1=`git_show_parent_commit $testroot/repo`
 	local new_commit2=`git_show_head $testroot/repo`
 
@@ -771,7 +791,7 @@ test_histedit_fold_last_commit() {
 	test_done "$testroot" "$ret"
 }
 
-test_histedit_missing_commit() {
+test_histedit_missing_commit_pick() {
 	local testroot=`test_init histedit_missing_commit`
 
 	local orig_commit=`git_show_head $testroot/repo`
@@ -795,7 +815,6 @@ test_histedit_missing_commit() {
 	fi
 
 	echo "pick $old_commit1" > $testroot/histedit-script
-	echo "mesg committing changes" >> $testroot/histedit-script
 
 	(cd $testroot/wt && got histedit -F $testroot/histedit-script \
 		> $testroot/stdout 2> $testroot/stderr)
@@ -818,6 +837,63 @@ test_histedit_missing_commit() {
 	test_done "$testroot" "$ret"
 }
 
+test_histedit_missing_commit_mesg() {
+	local testroot=`test_init histedit_missing_commit`
+
+	local orig_commit=`git_show_head $testroot/repo`
+
+	echo "modified alpha on master" > $testroot/repo/alpha
+	git -C $testroot/repo rm -q beta
+	echo "new file on master" > $testroot/repo/epsilon/new
+	git -C $testroot/repo add epsilon/new
+	git_commit $testroot/repo -m "committing changes"
+	local old_commit1=`git_show_head $testroot/repo`
+
+	echo "modified zeta on master" > $testroot/repo/epsilon/zeta
+	git_commit $testroot/repo -m "committing to zeta on master"
+	local old_commit2=`git_show_head $testroot/repo`
+
+	got checkout -c $orig_commit $testroot/repo $testroot/wt > /dev/null
+	ret=$?
+	if [ $ret -ne 0 ]; then
+		test_done "$testroot" "$ret"
+		return 1
+	fi
+
+	cat > $testroot/editor.sh <<EOF
+#!/bin/sh
+ed -s "\$1" <<-EOF
+	,s/.*/committing folded changes/
+	w
+	EOF
+EOF
+	chmod +x $testroot/editor.sh
+
+	echo "mesg $old_commit1" > $testroot/histedit-script
+
+	(cd $testroot/wt && env EDITOR="$testroot/editor.sh" \
+		VISUAL="$testroot/editor.sh" \
+		got histedit -F $testroot/histedit-script > $testroot/stdout \
+			2>$testroot/stderr)
+
+	ret=$?
+	if [ $ret -eq 0 ]; then
+		echo "histedit succeeded unexpectedly" >&2
+		test_done "$testroot" "1"
+		return 1
+	fi
+
+	echo "got: commit $old_commit2 missing from histedit script" \
+		> $testroot/stderr.expected
+
+	cmp -s $testroot/stderr.expected $testroot/stderr
+	ret=$?
+	if [ $ret -ne 0 ]; then
+		diff -u $testroot/stderr.expected $testroot/stderr
+	fi
+	test_done "$testroot" "$ret"
+}
+
 test_histedit_abort() {
 	local testroot=`test_init histedit_abort`
 
@@ -845,7 +921,6 @@ test_histedit_abort() {
 	touch $testroot/wt/unversioned-file
 
 	echo "edit $old_commit1" > $testroot/histedit-script
-	echo "mesg committing changes" >> $testroot/histedit-script
 	echo "pick $old_commit2" >> $testroot/histedit-script
 
 	(cd $testroot/wt && got histedit -F $testroot/histedit-script \
@@ -1051,7 +1126,6 @@ test_histedit_path_prefix_edit() {
 	fi
 
 	echo "edit $old_commit1" > $testroot/histedit-script
-	echo "mesg modified zeta" >> $testroot/histedit-script
 
 	(cd $testroot/wt && got histedit -F $testroot/histedit-script \
 		> $testroot/stdout 2> $testroot/stderr)
@@ -1120,8 +1194,19 @@ test_histedit_path_prefix_edit() {
 		test_done "$testroot" "$ret"
 		return 1
 	fi
+	
+	cat > $testroot/editor.sh <<EOF
+#!/bin/sh
+ed -s "\$1" <<-EOF
+	,s/.*/modified zeta/
+	w
+	EOF
+EOF
+	chmod +x $testroot/editor.sh
 
-	(cd $testroot/wt && got histedit -c > $testroot/stdout)
+	(cd $testroot/wt && env EDITOR="$testroot/editor.sh" \
+		VISUAL="$testroot/editor.sh" \
+		got histedit -c > $testroot/stdout)
 
 	local new_commit1=`git_show_head $testroot/repo`
 	local short_new_commit1=`trim_obj_id 28 $new_commit1`
@@ -1244,13 +1329,23 @@ test_histedit_fold_last_commit_swap() {
 		return 1
 	fi
 
+	cat > $testroot/editor.sh <<EOF
+#!/bin/sh
+ed -s "\$1" <<-EOF
+	,s/.*/committing folded changes/
+	w
+	EOF
+EOF
+	chmod +x $testroot/editor.sh
+
 	# fold commit2 into commit1 (requires swapping commits)
 	echo "fold $old_commit2" > $testroot/histedit-script
-	echo "pick $old_commit1" >> $testroot/histedit-script
-	echo "mesg committing folded changes" >> $testroot/histedit-script
+	echo "mesg $old_commit1" >> $testroot/histedit-script
 
-	(cd $testroot/wt && got histedit -F $testroot/histedit-script \
-		> $testroot/stdout 2> $testroot/stderr)
+	(cd $testroot/wt && env EDITOR="$testroot/editor.sh" \
+		VISUAL="$testroot/editor.sh" \
+		got histedit -F $testroot/histedit-script > $testroot/stdout \
+		2> $testroot/stderr)
 
 	ret=$?
 	if [ $ret -ne 0 ]; then
@@ -1470,13 +1565,22 @@ test_histedit_fold_add_delete() {
 		return 1
 	fi
 
+	cat > $testroot/editor.sh <<EOF
+#!/bin/sh
+ed -s "\$1" <<-EOF
+	,s/.*/folded changes/
+	w
+	EOF
+EOF
+	chmod +x $testroot/editor.sh
+
 	echo "fold $old_commit1" > $testroot/histedit-script
 	echo "fold $old_commit2" >> $testroot/histedit-script
 	echo "pick $old_commit3" >> $testroot/histedit-script
-	echo "mesg folded changes" >> $testroot/histedit-script
 
-	(cd $testroot/wt && got histedit -F $testroot/histedit-script \
-		> $testroot/stdout)
+	(cd $testroot/wt && env EDITOR="$testroot/editor.sh" \
+		VISUAL="$testroot/editor.sh" \
+		got histedit -F $testroot/histedit-script > $testroot/stdout)
 
 	local new_commit1=`git_show_head $testroot/repo`
 
@@ -1565,12 +1669,21 @@ test_histedit_fold_edit_delete() {
 		return 1
 	fi
 
+	cat > $testroot/editor.sh <<EOF
+#!/bin/sh
+ed -s "\$1" <<-EOF
+	,s/.*/folded changes/
+	w
+	EOF
+EOF
+	chmod +x $testroot/editor.sh
+
 	echo "fold $old_commit1" > $testroot/histedit-script
 	echo "pick $old_commit2" >> $testroot/histedit-script
-	echo "mesg folded changes" >> $testroot/histedit-script
 
-	(cd $testroot/wt && got histedit -F $testroot/histedit-script \
-		> $testroot/stdout)
+	(cd $testroot/wt && env EDITOR="$testroot/editor.sh" \
+		VISUAL="$testroot/editor.sh" \
+		got histedit -F $testroot/histedit-script > $testroot/stdout)
 
 	local new_commit1=`git_show_head $testroot/repo`
 
@@ -1645,12 +1758,21 @@ test_histedit_fold_delete_add() {
 		return 1
 	fi
 
+	cat > $testroot/editor.sh <<EOF
+#!/bin/sh
+ed -s "\$1" <<-EOF
+	,s/.*/folded changes/
+	w
+	EOF
+EOF
+	chmod +x $testroot/editor.sh
+
 	echo "fold $old_commit1" > $testroot/histedit-script
 	echo "pick $old_commit2" >> $testroot/histedit-script
-	echo "mesg folded changes" >> $testroot/histedit-script
-
-	(cd $testroot/wt && got histedit -F $testroot/histedit-script \
-		> $testroot/stdout)
+
+	(cd $testroot/wt && env EDITOR="$testroot/editor.sh" \
+		VISUAL="$testroot/editor.sh" \
+		got histedit -F $testroot/histedit-script > $testroot/stdout)
 
 	local new_commit1=`git_show_head $testroot/repo`
 	
@@ -2136,129 +2258,9 @@ EOF
 	if [ $ret -ne 0 ]; then
 		diff -u $testroot/content.expected $testroot/content
 		test_done "$testroot" "$ret"
-		return 1
-	fi
-
-	test_done "$testroot" $ret
-}
-
-test_histedit_mesg_invalid() {
-	local testroot=`test_init mesg_invalid`
-
-	local orig_commit=`git_show_head $testroot/repo`
-
-	echo "modified alpha on master" > $testroot/repo/alpha
-	git -C $testroot/repo rm -q beta
-	echo "new file on master" > $testroot/repo/epsilon/new
-	git -C $testroot/repo add epsilon/new
-	git_commit $testroot/repo -m 'committing changes'
-	local old_commit1=`git_show_head $testroot/repo`
-
-	echo "modified zeta on master" > $testroot/repo/epsilon/zeta
-	git_commit $testroot/repo -m 'committing to zeto on master'
-	local old_commit2=`git_show_head $testroot/repo`
-
-	got checkout -c $orig_commit $testroot/repo $testroot/wt > /dev/null
-	ret=$?
-	if [ $ret -ne 0 ]; then
-		test_done "$testroot" $ret
-		return 1
-	fi
-
-	# try with a leading mesg
-
-	echo "mesg something something" > $testroot/histedit-script
-	echo "pick $old_commit1" >> $testroot/histedit-script
-	echo "pick $old_commit2" >> $testroot/histedit-script
-
-	(cd $testroot/wt && got histedit -F $testroot/histedit-script \
-		> $testroot/stdout 2> $testroot/stderr)
-	ret=$?
-	if [ $ret -eq 0 ]; then
-		echo "histedit succeeded unexpectedly" >&2
-		test_done "$testroot" 1
-		return 1
-	fi
-
-	echo "got: bad histedit command" > $testroot/stderr.expected
-	cmp -s $testroot/stderr.expected $testroot/stderr
-	ret=$?
-	if [ $ret -ne 0 ]; then
-		diff -u $testroot/stderr.expected $testroot/stderr
-		test_done "$testroot" $ret
-		return 1
-	fi
-
-	# try again with mesg -> mesg
-
-	echo "pick $old_commit1" > $testroot/histedit-script
-	echo "mesg something something" >> $testroot/histedit-script
-	echo "mesg something something else" >> $testroot/histedit-script
-	echo "pick $old_commit2" >> $testroot/histedit-script
-
-	(cd $testroot/wt && got histedit -F $testroot/histedit-script \
-		> $testroot/stdout 2> $testroot/stderr)
-	ret=$?
-	if [ $ret -eq 0 ]; then
-		echo "histedit succeeded unexpectedly" >&2
-		test_done "$testroot" 1
-		return 1
-	fi
-
-	echo "got: bad histedit command" > $testroot/stderr.expected
-	cmp -s $testroot/stderr.expected $testroot/stderr
-	ret=$?
-	if [ $ret -ne 0 ]; then
-		diff -u $testroot/stderr.expected $testroot/stderr
-		test_done "$testroot" $ret
-		return 1
-	fi
-
-	# try again with drop -> mesg
-
-	echo "drop $old_commit1" > $testroot/histedit-script
-	echo "mesg something something" >> $testroot/histedit-script
-	echo "pick $old_commit2" >> $testroot/histedit-script
-
-	(cd $testroot/wt && got histedit -F $testroot/histedit-script \
-		> $testroot/stdout 2> $testroot/stderr)
-	ret=$?
-	if [ $ret -eq 0 ]; then
-		echo "histedit succeeded unexpectedly" >&2
-		test_done "$testroot" 1
-		return 1
-	fi
-
-	echo "got: bad histedit command" > $testroot/stderr.expected
-	cmp -s $testroot/stderr.expected $testroot/stderr
-	ret=$?
-	if [ $ret -ne 0 ]; then
-		diff -u $testroot/stderr.expected $testroot/stderr
-		test_done "$testroot" $ret
 		return 1
 	fi
 
-	# try again with fold -> mesg
-
-	echo "fold $old_commit1" > $testroot/histedit-script
-	echo "mesg something something" >> $testroot/histedit-script
-	echo "pick $old_commit2" >> $testroot/histedit-script
-
-	(cd $testroot/wt && got histedit -F $testroot/histedit-script \
-		> $testroot/stdout 2> $testroot/stderr)
-	ret=$?
-	if [ $ret -eq 0 ]; then
-		echo "histedit succeeded unexpectedly" >&2
-		test_done "$testroot" 1
-		return 1
-	fi
-
-	echo "got: bad histedit command" > $testroot/stderr.expected
-	cmp -s $testroot/stderr.expected $testroot/stderr
-	ret=$?
-	if [ $ret -ne 0 ]; then
-		diff -u $testroot/stderr.expected $testroot/stderr
-	fi
 	test_done "$testroot" $ret
 }
 
@@ -2354,13 +2356,22 @@ test_histedit_umask() {
 		return 1
 	fi
 
+	cat > $testroot/editor.sh <<EOF
+#!/bin/sh
+ed -s "\$1" <<-EOF
+	,s/.*/folding changes/
+	w
+	EOF
+EOF
+	chmod +x $testroot/editor.sh
+
 	echo fold $commit1 >$testroot/histedit-script
 	echo fold $commit2 >>$testroot/histedit-script
 	echo pick $commit3 >>$testroot/histedit-script
-	echo mesg folding changes >>$testroot/histedit-script
 
 	# using a subshell to avoid clobbering global umask
 	(umask 077 && cd "$testroot/wt" && \
+		env EDITOR="$testroot/editor.sh" VISUAL="$testroot/editor.sh" \
 		got histedit -F "$testroot/histedit-script") >/dev/null
 	ret=$?
 
@@ -2604,7 +2615,8 @@ run_test test_histedit_drop
 run_test test_histedit_fold
 run_test test_histedit_edit
 run_test test_histedit_fold_last_commit
-run_test test_histedit_missing_commit
+run_test test_histedit_missing_commit_pick
+run_test test_histedit_missing_commit_mesg
 run_test test_histedit_abort
 run_test test_histedit_path_prefix_drop
 run_test test_histedit_path_prefix_edit
@@ -2619,7 +2631,6 @@ run_test test_histedit_fold_only
 run_test test_histedit_fold_only_empty_logmsg
 run_test test_histedit_edit_only
 run_test test_histedit_prepend_line
-run_test test_histedit_mesg_invalid
 run_test test_histedit_resets_committer
 run_test test_histedit_umask
 run_test test_histedit_mesg_filemode_change