Add test for closed branches

t/smoke-test.expected

@@ -298,3 +298,25 @@ Added file in branch åäö
 from :41
 M 100644 :42 a0d01fcbff5d86327d542687dcfd8b299d054147
 
+blob
+mark :44
+data 24
+this-is-a-closed-branch
+
+commit refs/heads/this-is-a-closed-branch
+mark :45
+author Grevious Bodily Harmsworth <gbh@example.com> 1679083200 +0000
+committer Grevious Bodily Harmsworth <gbh@example.com> 1679083200 +0000
+data 45
+Added file in branch this-is-a-closed-branch
+from :43
+M 100644 :44 9d7dfd0ecce946dca320dd7826e5b9f97a0e9e79
+
+commit refs/heads/this-is-a-closed-branch
+mark :46
+author Grevious Bodily Harmsworth <gbh@example.com> 1679086800 +0000
+committer Grevious Bodily Harmsworth <gbh@example.com> 1679086800 +0000
+data 39
+Closing branch this-is-a-closed-branch
+from :45
+

t/smoke-test.t

@@ -108,6 +108,8 @@ commit_rest() {
 	make-branch "_1" 17 &&
 	make-branch "Feature- 12V Vac \"Venom\"" 18 &&
 	make-branch "åäö" 19 &&
+	make-branch "this-is-a-closed-branch" 20 &&
+	close-branch "this-is-a-closed-branch" 21 &&
 
 	hg bookmark bm-for-the-rest
 	)
@@ -121,6 +123,11 @@ make-branch() {
     hg commit -d "2023-03-17 $2:00Z" -m "Added file in branch $1"
 }
 
+close-branch() {
+	hg branch "$1"
+	hg commit --close-branch -d "2023-03-17 $2:00Z" -m "Closing branch $1"
+}
+
 setup
 
 test_expect_success 'all in one' '