Multiple fixes with respect to .Pf:

* The first argument of .Pf is not parsed.
* Normal delimiter handling does not apply to the first argument of .Pf.
* Warn if nothing follows a prefix (inspired by groff_mdoc(7)).
* In that case, do not suppress spacing.

8 files changed, 33 insertions, 10 deletions

diff --git a/mandoc.1 b/mandoc.1
index cd1b206b..10194ae6 100644
--- a/mandoc.1
+++ b/mandoc.1
@@ -1054,6 +1054,14 @@ argument is invalid.
 The default font
 .Cm \efR
 is used instead.
+.It Sy "nothing follows prefix"
+.Pq mdoc
+A
+.Ic \&Pf
+macro has no argument, or only one argument and no macro follows
+on the same input line.
+This defeats its purpose; in particular, spacing is not suppressed
+before the text or macros following on the next input line.
 .It Sy "missing -std argument, adding it"
 .Pq mdoc
 An
diff --git a/mandoc.h b/mandoc.h
index eed7f689..18af6fcf 100644
--- a/mandoc.h
+++ b/mandoc.h
@@ -103,6 +103,7 @@ enum	mandocerr {
 	MANDOCERR_IT_NOBODY, /* empty list item: Bl -type It */
 	MANDOCERR_BF_NOFONT, /* missing font type, using \fR: Bf */
 	MANDOCERR_BF_BADFONT, /* unknown font type, using \fR: Bf font */
+	MANDOCERR_PF_SKIP, /* nothing follows prefix: Pf arg */
 	MANDOCERR_ARG_STD, /* missing -std argument, adding it: macro */
 	MANDOCERR_EQN_NOBOX, /* missing eqn box, using "": op */
 
diff --git a/mdoc_html.c b/mdoc_html.c
index ed589127..fe333655 100644
--- a/mdoc_html.c
+++ b/mdoc_html.c
@@ -1869,7 +1869,8 @@ static void
 mdoc_pf_post(MDOC_ARGS)
 {
 
-	h->flags |= HTML_NOSPACE;
+	if ( ! (n->next == NULL || n->next->flags & MDOC_LINE))
+		h->flags |= HTML_NOSPACE;
 }
 
 static int
diff --git a/mdoc_macro.c b/mdoc_macro.c
index 8554c2d4..6d1556b4 100644
--- a/mdoc_macro.c
+++ b/mdoc_macro.c
@@ -1396,7 +1396,7 @@ in_line_argn(MACRO_PROT_ARGS)
 	char		*p;
 	enum mdoct	 ntok;
 
-	nl = MDOC_NEWLINE & mdoc->flags;
+	nl = mdoc->flags & MDOC_NEWLINE;
 
 	/*
 	 * A line macro that has a fixed number of arguments (maxargs).
@@ -1428,11 +1428,18 @@ in_line_argn(MACRO_PROT_ARGS)
 
 	mdoc_argv(mdoc, line, tok, &arg, pos, buf);
 
-	for (flushed = j = 0; ; ) {
+	p = NULL;
+	flushed = j = 0;
+	for (;;) {
 		la = *pos;
 		ac = mdoc_args(mdoc, line, pos, buf, tok, &p);
-		if (ac == ARGS_PUNCT || ac == ARGS_EOLN)
+		if (ac == ARGS_PUNCT || ac == ARGS_EOLN) {
+			if (j < 2 && tok == MDOC_Pf)
+				mandoc_vmsg(MANDOCERR_PF_SKIP,
+				    mdoc->parse, line, ppos, "Pf %s",
+				    p == NULL ? "at eol" : p);
 			break;
+		}
 
 		if ( ! (mdoc_macros[tok].flags & MDOC_IGNDELIM) &&
 		    ac != ARGS_QWORD && j == 0 &&
@@ -1447,8 +1454,8 @@ in_line_argn(MACRO_PROT_ARGS)
 			flushed = 1;
 		}
 
-		ntok = ac == ARGS_QWORD ? MDOC_MAX :
-		    lookup(mdoc, tok, line, la, p);
+		ntok = (ac == ARGS_QWORD || (tok == MDOC_Pf && j == 0)) ?
+		    MDOC_MAX : lookup(mdoc, tok, line, la, p);
 
 		if (ntok != MDOC_MAX) {
 			if ( ! flushed)
@@ -1471,8 +1478,11 @@ in_line_argn(MACRO_PROT_ARGS)
 		j++;
 	}
 
-	if (j == 0)
+	if (j == 0) {
 		mdoc_elem_alloc(mdoc, line, ppos, tok, arg);
+		if (ac == ARGS_PUNCT && tok == MDOC_Pf)
+			append_delims(mdoc, line, pos, buf);
+	}
 	if ( ! flushed)
 		rew_elem(mdoc, tok);
 	if (nl)
diff --git a/mdoc_man.c b/mdoc_man.c
index 937a4251..458706c5 100644
--- a/mdoc_man.c
+++ b/mdoc_man.c
@@ -1602,7 +1602,8 @@ static void
 post_pf(DECL_ARGS)
 {
 
-	outflags &= ~MMAN_spc;
+	if ( ! (n->next == NULL || n->next->flags & MDOC_LINE))
+		outflags &= ~MMAN_spc;
 }
 
 static int
diff --git a/mdoc_term.c b/mdoc_term.c
index be0a2ab0..4b4d12d9 100644
--- a/mdoc_term.c
+++ b/mdoc_term.c
@@ -1734,7 +1734,8 @@ static void
 termp_pf_post(DECL_ARGS)
 {
 
-	p->flags |= TERMP_NOSPACE;
+	if ( ! (n->next == NULL || n->next->flags & MDOC_LINE))
+		p->flags |= TERMP_NOSPACE;
 }
 
 static int
diff --git a/mdoc_validate.c b/mdoc_validate.c
index 18946b52..88ee2537 100644
--- a/mdoc_validate.c
+++ b/mdoc_validate.c
@@ -210,7 +210,7 @@ static	const struct valids mdoc_valids[MDOC_MAX] = {
 	{ NULL, NULL },				/* Nx */
 	{ NULL, NULL },				/* Ox */
 	{ NULL, NULL },				/* Pc */
-	{ NULL, ewarn_eq1 },			/* Pf */
+	{ NULL, NULL },				/* Pf */
 	{ NULL, NULL },				/* Po */
 	{ NULL, NULL },				/* Pq */
 	{ NULL, NULL },				/* Qc */
diff --git a/read.c b/read.c
index 75fa3693..ecb0d827 100644
--- a/read.c
+++ b/read.c
@@ -146,6 +146,7 @@ static	const char * const	mandocerrs[MANDOCERR_MAX] = {
 	"empty list item",
 	"missing font type, using \\fR",
 	"unknown font type, using \\fR",
+	"nothing follows prefix",
 	"missing -std argument, adding it",
 	"missing eqn box, using \"\"",