orphan/unborn: fix use of 'orphan' in end-user facing messages

"orphan branch" is not even grammatical ("orphaned branch" is), and
we have been using "unborn branch" to mean the state where the HEAD
points at a branch that does not yet exist.

Update end-user facing messages to correct them.  There are cases
other random words are used (e.g., "unparented branch") but now we
have a glossary entry, use the term "unborn branch" consistently.

Signed-off-by: Junio C Hamano <[email protected]>

builtin/checkout.c

@@ -1627,7 +1627,7 @@ static struct option *add_common_switch_branch_options(
 			parse_opt_tracking_mode),
 		OPT__FORCE(&opts->force, N_("force checkout (throw away local modifications)"),
 			   PARSE_OPT_NOCOMPLETE),
-		OPT_STRING(0, "orphan", &opts->new_orphan_branch, N_("new-branch"), N_("new unparented branch")),
+		OPT_STRING(0, "orphan", &opts->new_orphan_branch, N_("new-branch"), N_("new unborn branch")),
 		OPT_BOOL_F(0, "overwrite-ignore", &opts->overwrite_ignore,
 			   N_("update ignored files (default)"),
 			   PARSE_OPT_NOCOMPLETE),

builtin/worktree.c

@@ -49,14 +49,14 @@
 	_("No possible source branch, inferring '--orphan'")
 
 #define WORKTREE_ADD_ORPHAN_WITH_DASH_B_HINT_TEXT \
-	_("If you meant to create a worktree containing a new orphan branch\n" \
+	_("If you meant to create a worktree containing a new unborn branch\n" \
 	"(branch with no commits) for this repository, you can do so\n" \
 	"using the --orphan flag:\n" \
 	"\n" \
 	"    git worktree add --orphan -b %s %s\n")
 
 #define WORKTREE_ADD_ORPHAN_NO_DASH_B_HINT_TEXT \
-	_("If you meant to create a worktree containing a new orphan branch\n" \
+	_("If you meant to create a worktree containing a new unborn branch\n" \
 	"(branch with no commits) for this repository, you can do so\n" \
 	"using the --orphan flag:\n" \
 	"\n" \
@@ -784,7 +784,7 @@ static int add(int ac, const char **av, const char *prefix)
 			   N_("create a new branch")),
 		OPT_STRING('B', NULL, &new_branch_force, N_("branch"),
 			   N_("create or reset a branch")),
-		OPT_BOOL(0, "orphan", &opts.orphan, N_("create unborn/orphaned branch")),
+		OPT_BOOL(0, "orphan", &opts.orphan, N_("create unborn branch")),
 		OPT_BOOL('d', "detach", &opts.detach, N_("detach HEAD at named commit")),
 		OPT_BOOL(0, "checkout", &opts.checkout, N_("populate the new working tree")),
 		OPT_BOOL(0, "lock", &keep_locked, N_("keep the new working tree locked")),

t/t2400-worktree-add.sh

@@ -415,7 +415,7 @@ test_wt_add_orphan_hint () {
 		git -C repo switch --orphan noref &&
 		test_must_fail git -C repo worktree add $opts foobar/ 2>actual &&
 		! grep "error: unknown switch" actual &&
-		grep "hint: If you meant to create a worktree containing a new orphan branch" actual &&
+		grep "hint: If you meant to create a worktree containing a new unborn branch" actual &&
 		if [ $use_branch -eq 1 ]
 		then
 			grep -E "^hint: +git worktree add --orphan -b [^ ]+ [^ ]+$" actual
@@ -436,7 +436,7 @@ test_expect_success "'worktree add' doesn't show orphan hint in bad/orphan HEAD
 	(cd repo && test_commit commit) &&
 	test_must_fail git -C repo worktree add --quiet foobar_branch foobar/ 2>actual &&
 	! grep "error: unknown switch" actual &&
-	! grep "hint: If you meant to create a worktree containing a new orphan branch" actual
+	! grep "hint: If you meant to create a worktree containing a new unborn branch" actual
 '
 
 test_expect_success 'local clone from linked checkout' '
@@ -709,7 +709,7 @@ test_expect_success 'git worktree --no-guess-remote option overrides config' '
 test_dwim_orphan () {
 	local info_text="No possible source branch, inferring '--orphan'" &&
 	local fetch_error_text="fatal: No local or remote refs exist despite at least one remote" &&
-	local orphan_hint="hint: If you meant to create a worktree containing a new orphan branch" &&
+	local orphan_hint="hint: If you meant to create a worktree containing a new unborn branch" &&
 	local invalid_ref_regex="^fatal: invalid reference: " &&
 	local bad_combo_regex="^fatal: '[-a-z]*' and '[-a-z]*' cannot be used together" &&