warn about .Ns macros that have no effect because they are followed

by an isolated closing delimiter; inspired by mdoclint

6 files changed, 29 insertions, 7 deletions

diff --git a/mandoc.1 b/mandoc.1
index 1d731558..4d5eeb94 100644
--- a/mandoc.1
+++ b/mandoc.1
@@ -1175,7 +1175,9 @@ The paragraph macro is moved after the end of the list.
 .Pq mdoc
 An input line begins with an
 .Ic \&Ns
-macro.
+macro, or the next argument after an
+.Ic \&Ns
+macro is an isolated closing delimiter.
 The macro is ignored.
 .It Sy "blocks badly nested"
 .Pq mdoc
diff --git a/mdoc_validate.c b/mdoc_validate.c
index 42a51afd..5be54f6b 100644
--- a/mdoc_validate.c
+++ b/mdoc_validate.c
@@ -1983,10 +1983,13 @@ post_hyph(POST_ARGS)
 static void
 post_ns(POST_ARGS)
 {
+	struct roff_node	*n;
 
-	if (mdoc->last->flags & NODE_LINE)
+	n = mdoc->last;
+	if (n->flags & NODE_LINE ||
+	    (n->next != NULL && n->next->flags & NODE_DELIMC))
 		mandoc_msg(MANDOCERR_NS_SKIP, mdoc->parse,
-		    mdoc->last->line, mdoc->last->pos, NULL);
+		    n->line, n->pos, NULL);
 }
 
 static void
diff --git a/regress/mdoc/Ns/position.in b/regress/mdoc/Ns/position.in
index 1325df25..56fc5de6 100644
--- a/regress/mdoc/Ns/position.in
+++ b/regress/mdoc/Ns/position.in
@@ -1,4 +1,4 @@
-.Dd September 15, 2013
+.Dd June 27, 2017
 .Dt NS-POSITION 1
 .Os OpenBSD
 .Sh NAME
@@ -20,6 +20,12 @@ After some macro and a block closing:
 In the middle of a macro line:
 .Oo before Oc Ns Op after
 .Pp
+After closing punctuation:
+.Oo before Oc : Ns Op after
+.Pp
+Before closing punctuation:
+.Oo before Oc Ns : Op after
+.Pp
 At the end of a macro line:
 .Oo before Oc Ns
 .Op after
diff --git a/regress/mdoc/Ns/position.out_ascii b/regress/mdoc/Ns/position.out_ascii
index a2bd6c45..26de0562 100644
--- a/regress/mdoc/Ns/position.out_ascii
+++ b/regress/mdoc/Ns/position.out_ascii
@@ -12,8 +12,12 @@ DDEESSCCRRIIPPTTIIOONN
 
      In the middle of a macro line: [before][after]
 
+     After closing punctuation: [before]:[after]
+
+     Before closing punctuation: [before]: [after]
+
      At the end of a macro line: [before][after]
 
      At the end of partial implicit: [before][after]
 
-OpenBSD                       September 15, 2013                       OpenBSD
+OpenBSD                          June 27, 2017                         OpenBSD
diff --git a/regress/mdoc/Ns/position.out_lint b/regress/mdoc/Ns/position.out_lint
index 91695895..aa1f3275 100644
--- a/regress/mdoc/Ns/position.out_lint
+++ b/regress/mdoc/Ns/position.out_lint
@@ -1,4 +1,5 @@
 mandoc: position.in:3:5: BASE: operating system explicitly specified: Os OpenBSD (OpenBSD)
-mandoc: position.in:1:5: BASE: Mdocdate missing: Dd September (OpenBSD)
+mandoc: position.in:1:5: BASE: Mdocdate missing: Dd June (OpenBSD)
 mandoc: position.in:10:2: WARNING: skipping no-space macro
+mandoc: position.in:27:15: WARNING: skipping no-space macro
 mandoc: position.in: BASE: RCS id missing: (OpenBSD)
diff --git a/regress/mdoc/Ns/position.out_markdown b/regress/mdoc/Ns/position.out_markdown
index 14414a3e..8b6c509c 100644
--- a/regress/mdoc/Ns/position.out_markdown
+++ b/regress/mdoc/Ns/position.out_markdown
@@ -20,10 +20,16 @@ still before]\[after]
 In the middle of a macro line:
 \[before]\[after]
 
+After closing punctuation:
+\[before]:\[after]
+
+Before closing punctuation:
+\[before]: \[after]
+
 At the end of a macro line:
 \[before]\[after]
 
 At the end of partial implicit:
 \[before]\[after]
 
-OpenBSD - September 15, 2013
+OpenBSD - June 27, 2017