completion: loosen and document the requirement around completing alias

Recently we started to tell users to spell ": git foo ;" with
space(s) around 'foo' for an alias to be completed similarly
to the 'git foo' command.  It however is easy to also allow users to
spell it in a more natural way with the semicolon attached to 'foo',
i.e. ": git foo;".  Also, add a comment to note that 'git' is optional
and writing ": foo;" would complete the alias just fine.

Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 18 insertions, 0 deletions

diff --git a/t/t9902-completion.sh b/t/t9902-completion.sh
index 47e20fb8b1..a7c3b4eb63 100755
--- a/t/t9902-completion.sh
+++ b/t/t9902-completion.sh
@@ -2464,6 +2464,24 @@ test_expect_success 'completion used <cmd> completion for alias: !f() { : git <c
 	EOF
 '
 
+test_expect_success 'completion used <cmd> completion for alias: !f() { : <cmd> ; ... }' '
+	test_config alias.co "!f() { : checkout ; if ... } f" &&
+	test_completion "git co m" <<-\EOF
+	main Z
+	mybranch Z
+	mytag Z
+	EOF
+'
+
+test_expect_success 'completion used <cmd> completion for alias: !f() { : <cmd>; ... }' '
+	test_config alias.co "!f() { : checkout; if ... } f" &&
+	test_completion "git co m" <<-\EOF
+	main Z
+	mybranch Z
+	mytag Z
+	EOF
+'
+
 test_expect_success 'completion without explicit _git_xxx function' '
 	test_completion "git version --" <<-\EOF
 	--build-options Z