Implement the roff .break request (break out of a .while loop).

Jan Stary <hans at stare dot cz> found it in an ancient groffer(1)
manual page (version 1.19) on MacOS X Mojave.
Having .break not implemented wasn't a particularly bright idea
because obviously, it tended to cause infinite loops.

3 files changed, 27 insertions, 2 deletions

diff --git a/regress/usr.bin/mandoc/roff/while/Makefile b/regress/usr.bin/mandoc/roff/while/Makefile
index ed970474667..42ce590a865 100644
--- a/regress/usr.bin/mandoc/roff/while/Makefile
+++ b/regress/usr.bin/mandoc/roff/while/Makefile
@@ -1,6 +1,6 @@
-# $OpenBSD: Makefile,v 1.1 2018/08/24 22:56:37 schwarze Exp $
+# $OpenBSD: Makefile,v 1.2 2019/04/21 22:43:00 schwarze Exp $
 
-REGRESS_TARGETS	= basic badargs into nesting outof
+REGRESS_TARGETS	= basic badargs break into nesting outof
 LINT_TARGETS	= badargs into nesting outof
 
 # mandoc defects:
diff --git a/regress/usr.bin/mandoc/roff/while/break.in b/regress/usr.bin/mandoc/roff/while/break.in
new file mode 100644
index 00000000000..11e7d2f5e99
--- /dev/null
+++ b/regress/usr.bin/mandoc/roff/while/break.in
@@ -0,0 +1,16 @@
+.\" $OpenBSD: break.in,v 1.1 2019/04/21 22:43:00 schwarze Exp $
+.Dd $Mdocdate: April 21 2019 $
+.Dt WHILE-BREAK 1
+.Os
+.Sh NAME
+.Nm while-break
+.Nd break request inside a while loop
+.Sh DESCRIPTION
+initial text
+.nr cnt 11 1
+.while n \{\
+\n-[cnt]
+.if !\n[cnt] .break
+\(en
+.\}
+final text
diff --git a/regress/usr.bin/mandoc/roff/while/break.out_ascii b/regress/usr.bin/mandoc/roff/while/break.out_ascii
new file mode 100644
index 00000000000..8e3f39b941b
--- /dev/null
+++ b/regress/usr.bin/mandoc/roff/while/break.out_ascii
@@ -0,0 +1,9 @@
+WHILE-BREAK(1)              General Commands Manual             WHILE-BREAK(1)
+
+NNAAMMEE
+     wwhhiillee--bbrreeaakk - break request inside a while loop
+
+DDEESSCCRRIIPPTTIIOONN
+     initial text 10 - 9 - 8 - 7 - 6 - 5 - 4 - 3 - 2 - 1 - 0 final text
+
+OpenBSD                         April 21, 2019                         OpenBSD