Multiple fixes with respect to in-line macros:

* .No selects the default font; relevant e.g. in .Bf blocks
* no need to force empty .Li elements
* closing delimiters as leading macro arguments do not suppress space
* opening delimiters at the end of a macro line do not suppress space
* correctly handle delimiter spacing in -Tman
As a side effect, these fixes let mandoc warn about empty .No macros
as requested by bentley@.

6 files changed, 84 insertions, 32 deletions

diff --git a/libmdoc.h b/libmdoc.h
index f0e5b961..c7a67705 100644
--- a/libmdoc.h
+++ b/libmdoc.h
@@ -1,7 +1,7 @@
 /*	$Id$ */
 /*
  * Copyright (c) 2008, 2009, 2010, 2011 Kristaps Dzonsons <kristaps@bsd.lv>
- * Copyright (c) 2013 Ingo Schwarze <schwarze@openbsd.org>
+ * Copyright (c) 2013, 2014 Ingo Schwarze <schwarze@openbsd.org>
  *
  * Permission to use, copy, modify, and distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
@@ -37,6 +37,7 @@ struct	mdoc {
 #define	MDOC_SYNOPSIS	 (1 << 7) /* SYNOPSIS-style formatting */
 #define	MDOC_KEEP	 (1 << 8) /* in a word keep */
 #define	MDOC_SMOFF	 (1 << 9) /* spacing is off */
+#define	MDOC_NODELIMC	 (1 << 10) /* disable closing delimiter handling */
 	enum mdoc_next	  next; /* where to put the next node */
 	struct mdoc_node *last; /* the last node parsed */
 	struct mdoc_node *first; /* the first node parsed */
diff --git a/mdoc_html.c b/mdoc_html.c
index 04d3883e..c64d38c4 100644
--- a/mdoc_html.c
+++ b/mdoc_html.c
@@ -98,6 +98,7 @@ static	int		  mdoc_mt_pre(MDOC_ARGS);
 static	int		  mdoc_ms_pre(MDOC_ARGS);
 static	int		  mdoc_nd_pre(MDOC_ARGS);
 static	int		  mdoc_nm_pre(MDOC_ARGS);
+static	int		  mdoc_no_pre(MDOC_ARGS);
 static	int		  mdoc_ns_pre(MDOC_ARGS);
 static	int		  mdoc_pa_pre(MDOC_ARGS);
 static	void		  mdoc_pf_post(MDOC_ARGS);
@@ -192,7 +193,7 @@ static	const struct htmlmdoc mdocs[MDOC_MAX] = {
 	{mdoc_quote_pre, mdoc_quote_post}, /* Eo */
 	{mdoc_xx_pre, NULL}, /* Fx */
 	{mdoc_ms_pre, NULL}, /* Ms */
-	{mdoc_igndelim_pre, NULL}, /* No */
+	{mdoc_no_pre, NULL}, /* No */
 	{mdoc_ns_pre, NULL}, /* Ns */
 	{mdoc_xx_pre, NULL}, /* Nx */
 	{mdoc_xx_pre, NULL}, /* Ox */
@@ -1884,6 +1885,16 @@ mdoc_rs_pre(MDOC_ARGS)
 }
 
 static int
+mdoc_no_pre(MDOC_ARGS)
+{
+	struct htmlpair	tag;
+
+	PAIR_CLASS_INIT(&tag, "none");
+	print_otag(h, TAG_CODE, 1, &tag);
+	return(1);
+}
+
+static int
 mdoc_li_pre(MDOC_ARGS)
 {
 	struct htmlpair	tag;
diff --git a/mdoc_macro.c b/mdoc_macro.c
index 183d0c73..16c99abb 100644
--- a/mdoc_macro.c
+++ b/mdoc_macro.c
@@ -147,8 +147,7 @@ const	struct mdoc_macro __mdoc_macros[MDOC_MAX] = {
 	{ blk_part_exp, MDOC_CALLABLE | MDOC_PARSED | MDOC_EXPLICIT }, /* Eo */
 	{ in_line_argn, MDOC_CALLABLE | MDOC_PARSED }, /* Fx */
 	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Ms */
-	{ in_line_argn, MDOC_CALLABLE | MDOC_PARSED |
-			MDOC_IGNDELIM | MDOC_JOIN }, /* No */
+	{ in_line, MDOC_CALLABLE | MDOC_PARSED | MDOC_JOIN }, /* No */
 	{ in_line_argn, MDOC_CALLABLE | MDOC_PARSED |
 			MDOC_IGNDELIM | MDOC_JOIN }, /* Ns */
 	{ in_line_argn, MDOC_CALLABLE | MDOC_PARSED }, /* Nx */
@@ -627,24 +626,22 @@ dword(struct mdoc *mdoc, int line, int col, const char *p,
 	if ( ! mdoc_word_alloc(mdoc, line, col, p))
 		return(0);
 
-	if (DELIM_OPEN == d)
-		mdoc->last->flags |= MDOC_DELIMO;
-
 	/*
-	 * Closing delimiters only suppress the preceding space
-	 * when they follow something, not when they start a new
-	 * block or element, and not when they follow `No'.
-	 *
-	 * XXX	Explicitly special-casing MDOC_No here feels
-	 *	like a layering violation.  Find a better way
-	 *	and solve this in the code related to `No'!
+	 * If the word consists of a bare delimiter,
+	 * flag the new node accordingly,
+	 * unless doing so was vetoed by the invoking macro.
+	 * Always clear the veto, it is only valid for one word.
 	 */
 
-	else if (DELIM_CLOSE == d && mdoc->last->prev &&
-	    mdoc->last->prev->tok != MDOC_No &&
+	if (d == DELIM_OPEN)
+		mdoc->last->flags |= MDOC_DELIMO;
+	else if (d == DELIM_CLOSE &&
+	    ! (mdoc->flags & MDOC_NODELIMC) &&
 	    mdoc->last->parent->tok != MDOC_Fd)
 		mdoc->last->flags |= MDOC_DELIMC;
 
+	mdoc->flags &= ~MDOC_NODELIMC;
+
 	return(1);
 }
 
@@ -843,7 +840,7 @@ blk_exp_close(MACRO_PROT_ARGS)
 static int
 in_line(MACRO_PROT_ARGS)
 {
-	int		 la, scope, cnt, mayopen, nc, nl;
+	int		 la, scope, cnt, firstarg, mayopen, nc, nl;
 	enum margverr	 av;
 	enum mdoct	 ntok;
 	enum margserr	 ac;
@@ -894,17 +891,40 @@ in_line(MACRO_PROT_ARGS)
 		return(0);
 	}
 
+	d = DELIM_NONE;
+	firstarg = 1;
 	mayopen = 1;
 	for (cnt = scope = 0;; ) {
 		la = *pos;
 		ac = mdoc_args(mdoc, line, pos, buf, tok, &p);
 
-		if (ARGS_ERROR == ac)
+		if (ac == ARGS_ERROR)
 			return(0);
-		if (ARGS_EOLN == ac)
+
+		/*
+		 * At the end of a macro line,
+		 * opening delimiters do not suppress spacing.
+		 */
+
+		if (ac == ARGS_EOLN) {
+			if (d == DELIM_OPEN)
+				mdoc->last->flags &= ~MDOC_DELIMO;
 			break;
-		if (ARGS_PUNCT == ac)
+		}
+
+		/*
+		 * The rest of the macro line is only punctuation,
+		 * to be handled by append_delims().
+		 * If there were no other arguments,
+		 * do not allow the first one to suppress spacing,
+		 * even if it turns out to be a closing one.
+		 */
+
+		if (ac == ARGS_PUNCT) {
+			if (cnt == 0 && nc == 0)
+				mdoc->flags |= MDOC_NODELIMC;
 			break;
+		}
 
 		ntok = ARGS_QWORD == ac ? MDOC_MAX : lookup(tok, p);
 
@@ -949,20 +969,19 @@ in_line(MACRO_PROT_ARGS)
 		if (DELIM_NONE != d) {
 			/*
 			 * If we encounter closing punctuation, no word
-			 * has been omitted, no scope is open, and we're
+			 * has been emitted, no scope is open, and we're
 			 * allowed to have an empty element, then start
 			 * a new scope.
 			 */
 			if ((d == DELIM_CLOSE ||
 			     (d == DELIM_MIDDLE && tok == MDOC_Fl)) &&
-			    (nc || tok == MDOC_Li) &&
-			    !scope && !cnt && mayopen) {
+			    !cnt && !scope && nc && mayopen) {
 				if ( ! mdoc_elem_alloc(mdoc,
 				    line, ppos, tok, arg))
 					return(0);
 				scope = 1;
 				cnt++;
-				if (MDOC_Li == tok || MDOC_Nm == tok)
+				if (MDOC_Nm == tok)
 					mayopen = 0;
 			}
 			/*
@@ -984,6 +1003,15 @@ in_line(MACRO_PROT_ARGS)
 			return(0);
 
 		/*
+		 * If the first argument is a closing delimiter,
+		 * do not suppress spacing before it.
+		 */
+
+		if (firstarg && d == DELIM_CLOSE && !nc)
+			mdoc->last->flags &= ~MDOC_DELIMC;
+		firstarg = 0;
+
+		/*
 		 * `Fl' macros have their scope re-opened with each new
 		 * word so that the `-' can be added to each one without
 		 * having to parse out spaces.
@@ -1533,8 +1561,6 @@ in_line_argn(MACRO_PROT_ARGS)
 	switch (tok) {
 	case MDOC_Ap:
 		/* FALLTHROUGH */
-	case MDOC_No:
-		/* FALLTHROUGH */
 	case MDOC_Ns:
 		/* FALLTHROUGH */
 	case MDOC_Ux:
diff --git a/mdoc_man.c b/mdoc_man.c
index 234b9929..e5d062c9 100644
--- a/mdoc_man.c
+++ b/mdoc_man.c
@@ -594,7 +594,11 @@ print_node(DECL_ARGS)
 			printf("\\&");
 			outflags &= ~MMAN_spc;
 		}
+		if (outflags & MMAN_Sm && ! (n->flags & MDOC_DELIMC))
+			outflags |= MMAN_spc_force;
 		print_word(n->string);
+		if (outflags & MMAN_Sm && ! (n->flags & MDOC_DELIMO))
+			outflags |= MMAN_spc;
 	} else {
 		/*
 		 * Conditionally run the pre-node action handler for a
diff --git a/mdoc_term.c b/mdoc_term.c
index c115e0eb..e513ad19 100644
--- a/mdoc_term.c
+++ b/mdoc_term.c
@@ -193,7 +193,7 @@ static	const struct termact termacts[MDOC_MAX] = {
 	{ termp_quote_pre, termp_quote_post }, /* Eo */
 	{ termp_xx_pre, NULL }, /* Fx */
 	{ termp_bold_pre, NULL }, /* Ms */
-	{ NULL, NULL }, /* No */
+	{ termp_li_pre, NULL }, /* No */
 	{ termp_ns_pre, NULL }, /* Ns */
 	{ termp_xx_pre, NULL }, /* Nx */
 	{ termp_xx_pre, NULL }, /* Ox */
diff --git a/mdoc_validate.c b/mdoc_validate.c
index 977bf073..b891af6e 100644
--- a/mdoc_validate.c
+++ b/mdoc_validate.c
@@ -209,7 +209,7 @@ static	const struct valids mdoc_valids[MDOC_MAX] = {
 	{ NULL, NULL },				/* Eo */
 	{ NULL, NULL },				/* Fx */
 	{ NULL, NULL },				/* Ms */
-	{ NULL, ewarn_eq0 },			/* No */
+	{ NULL, NULL },				/* No */
 	{ NULL, post_ns },			/* Ns */
 	{ NULL, NULL },				/* Nx */
 	{ NULL, NULL },				/* Ox */
@@ -353,6 +353,20 @@ mdoc_valid_post(struct mdoc *mdoc)
 	case MDOC_ROOT:
 		return(post_root(mdoc));
 	default:
+
+		/*
+		 * Closing delimiters are not special at the
+		 * beginning of a block, opening delimiters
+		 * are not special at the end.
+		 */
+
+		if (n->child != NULL)
+			n->child->flags &= ~MDOC_DELIMC;
+		if (n->last != NULL)
+			n->last->flags &= ~MDOC_DELIMO;
+
+		/* Call the macro's postprocessor. */
+
 		p = mdoc_valids[n->tok].post;
 		return(*p ? (*p)(mdoc) : 1);
 	}
@@ -1162,10 +1176,6 @@ post_defaults(POST_ARGS)
 		if ( ! mdoc_word_alloc(mdoc, nn->line, nn->pos, "..."))
 			return(0);
 		break;
-	case MDOC_Li:
-		if ( ! mdoc_word_alloc(mdoc, nn->line, nn->pos, ""))
-			return(0);
-		break;
 	case MDOC_Pa:
 		/* FALLTHROUGH */
 	case MDOC_Mt: