warn about commas in function arguments; inspired by mdoclint(1)

4 files changed, 34 insertions, 2 deletions

diff --git a/mandoc.1 b/mandoc.1
index ebb7df57..04902e35 100644
--- a/mandoc.1
+++ b/mandoc.1
@@ -1118,6 +1118,13 @@ macro has an invalid argument.
 It is used verbatim, with
 .Qq "AT&T UNIX "
 prefixed to it.
+.It Sy "comma in function argument"
+.Pq mdoc
+An argument of an
+.Ic \&Fa
+or
+.Ic \&Fn
+macro contains a comma; it should probably be split into two arguments.
 .It Sy "invalid content in Rs block"
 .Pq mdoc
 An
diff --git a/mandoc.h b/mandoc.h
index 24a2510a..4f7a193d 100644
--- a/mandoc.h
+++ b/mandoc.h
@@ -113,6 +113,7 @@ enum	mandocerr {
 	MANDOCERR_BL_REP, /* skipping duplicate list type: Bl -type */
 	MANDOCERR_BL_SKIPW, /* skipping -width argument: Bl -type */
 	MANDOCERR_AT_BAD, /* unknown AT&T UNIX version: At version */
+	MANDOCERR_FA_COMMA, /* comma in function argument: arg */
 	MANDOCERR_RS_BAD, /* invalid content in Rs block: macro */
 	MANDOCERR_SM_BAD, /* invalid Boolean argument: macro arg */
 	MANDOCERR_FT_BAD, /* unknown font, skipping request: ft font */
diff --git a/mdoc_validate.c b/mdoc_validate.c
index 23649490..15ee201b 100644
--- a/mdoc_validate.c
+++ b/mdoc_validate.c
@@ -100,6 +100,7 @@ static	int	 post_en(POST_ARGS);
 static	int	 post_es(POST_ARGS);
 static	int	 post_eoln(POST_ARGS);
 static	int	 post_ex(POST_ARGS);
+static	int	 post_fa(POST_ARGS);
 static	int	 post_fo(POST_ARGS);
 static	int	 post_hyph(POST_ARGS);
 static	int	 post_hyphtext(POST_ARGS);
@@ -157,10 +158,10 @@ static	const struct valids mdoc_valids[MDOC_MAX] = {
 	{ NULL, NULL },				/* Er */
 	{ NULL, NULL },				/* Ev */
 	{ pre_std, post_ex },			/* Ex */
-	{ NULL, NULL },				/* Fa */
+	{ NULL, post_fa },			/* Fa */
 	{ NULL, ewarn_ge1 },			/* Fd */
 	{ NULL, NULL },				/* Fl */
-	{ NULL, NULL },				/* Fn */
+	{ NULL, post_fa },			/* Fn */
 	{ NULL, NULL },				/* Ft */
 	{ NULL, NULL },				/* Ic */
 	{ NULL, ewarn_eq1 },			/* In */
@@ -1008,6 +1009,28 @@ post_fo(POST_ARGS)
 }
 
 static int
+post_fa(POST_ARGS)
+{
+	const struct mdoc_node *n;
+	const char *cp;
+
+	for (n = mdoc->last->child; n != NULL; n = n->next) {
+		for (cp = n->string; *cp != '\0'; cp++) {
+			/* Ignore callbacks and alterations. */
+			if (*cp == '(' || *cp == '{')
+				break;
+			if (*cp != ',')
+				continue;
+			mandoc_msg(MANDOCERR_FA_COMMA, mdoc->parse,
+			    n->line, n->pos + (cp - n->string),
+			    n->string);
+			break;
+		}
+	}
+	return(1);
+}
+
+static int
 post_vt(POST_ARGS)
 {
 	const struct mdoc_node *n;
diff --git a/read.c b/read.c
index b19059ed..346bee13 100644
--- a/read.c
+++ b/read.c
@@ -158,6 +158,7 @@ static	const char * const	mandocerrs[MANDOCERR_MAX] = {
 	"skipping duplicate list type",
 	"skipping -width argument",
 	"unknown AT&T UNIX version",
+	"comma in function argument",
 	"invalid content in Rs block",
 	"invalid Boolean argument",
 	"unknown font, skipping request",