From 0a5c3099d18d26970b778c9e74f2e27124dc1084 Mon Sep 17 00:00:00 2001
From: Eric Wong <e@80x24.org>
Date: Tue, 15 Oct 2019 20:19:36 +0000
Subject: [PATCH] doc: "check-man" target to ensure we stay <=80 cols

This should prevent future documentation changes from exceeding
the limit of standard terminals.
---
 Documentation/include.mk | 18 +++++++++++++++++-
 1 file changed, 17 insertions(+), 1 deletion(-)

diff --git a/Documentation/include.mk b/Documentation/include.mk
index 45e08573..4af8d455 100644
--- a/Documentation/include.mk
+++ b/Documentation/include.mk
@@ -13,6 +13,7 @@ MAN = man
 
 # this is "xml" on FreeBSD and maybe some other distros:
 XMLSTARLET = xmlstarlet
+AWK = awk
 
 # same as pod2text
 COLUMNS = 76
@@ -61,7 +62,9 @@ man8 := $(addsuffix .8, $(m8))
 
 all:: man html
 
-man: $(man1) $(man5) $(man7) $(man8)
+manpages = $(man1) $(man5) $(man7) $(man8)
+
+man: $(manpages)
 
 prefix ?= $(PREFIX)
 prefix ?= $(HOME)
@@ -86,6 +89,19 @@ doc_install :: install-man
 %.1 %.5 %.7 %.8 : Documentation/%.pod
 	$(podman) -s $(subst .,,$(suffix $@)) $< $@+ && mv $@+ $@
 
+# n.b. not sure if our usage of man(1) is portable or not, so not
+# enabled by default "check" target:
+# check :: check-man
+check_man = @echo CHECK80 $<;COLS=80 $(MAN) ./$^ | \
+	$(AWK) 'length>80{print;err=1}END{exit(err)}' >&2
+
+%.1.cols : %.1; $(check_man)
+%.5.cols : %.5; $(check_man)
+%.7.cols : %.7; $(check_man)
+%.8.cols : %.8; $(check_man)
+
+check-man :: $(addsuffix .cols, $(manpages))
+
 manuals :=
 manuals += $(m1)
 manuals += $(m5)
-- 
2.44.0