Introduce the concept of nodes that are semantically transparent:

they are skipped when looking for previous or following high-level
macros.  Examples include roff(7) .ft, .ll, and .ta, mdoc(7) .Sm
and .Tg, and man(7) .DT and .PD.  Use this concept for a variety
of improved decisions in various validators and formatters.

While here,
* remove a few const qualifiers on struct arguments that caused trouble;
* get rid of some more Yoda notation in the vicinity;
* and apply some other stylistic improvements in the vicinity.

I found this class of issues while considering .Tg patches from kn@.

3 files changed, 37 insertions, 2 deletions

diff --git a/regress/man/HP/Makefile b/regress/man/HP/Makefile
index 1e33cfb4..945f5339 100644
--- a/regress/man/HP/Makefile
+++ b/regress/man/HP/Makefile
@@ -1,6 +1,6 @@
-# $OpenBSD: Makefile,v 1.3 2019/01/06 04:41:15 schwarze Exp $
+# $OpenBSD: Makefile,v 1.4 2020/02/27 01:25:58 schwarze Exp $
 
-REGRESS_TARGETS = break literal macrotag manyargs spacing
+REGRESS_TARGETS = break literal macrotag manyargs spacing vert
 HTML_TARGETS	= literal
 
 .include <bsd.regress.mk>
diff --git a/regress/man/HP/vert.in b/regress/man/HP/vert.in
new file mode 100644
index 00000000..b433c7e0
--- /dev/null
+++ b/regress/man/HP/vert.in
@@ -0,0 +1,14 @@
+.\" $OpenBSD: vert.in,v 1.1 2020/02/27 01:25:58 schwarze Exp $
+.TH HP-VERT 1 "February 19, 2020"
+.SH NAME
+HP-vert \- vertical spacing before hanged lists
+.SH DESCRIPTION
+.PD 2v
+.HP
+Each hanged paragraph gets a sufficient amount of text
+to wrap to the next line.
+.HP
+Each hanged paragraph gets a sufficient amount of text
+to wrap to the next line.
+.LP
+Normal text.
diff --git a/regress/man/HP/vert.out_ascii b/regress/man/HP/vert.out_ascii
new file mode 100644
index 00000000..30fa3dd4
--- /dev/null
+++ b/regress/man/HP/vert.out_ascii
@@ -0,0 +1,21 @@
+HP-VERT(1)                  General Commands Manual                 HP-VERT(1)
+
+
+
+NNAAMMEE
+       HP-vert - vertical spacing before hanged lists
+
+DDEESSCCRRIIPPTTIIOONN
+       Each hanged paragraph gets a sufficient amount of text to wrap to the
+              next line.
+
+
+       Each hanged paragraph gets a sufficient amount of text to wrap to the
+              next line.
+
+
+       Normal text.
+
+
+
+OpenBSD                        February 19, 2020                    HP-VERT(1)