Add a new warning, "Prototype after '%s'"

Based on:
Subject: Re: [perl #36673] sub foo(@$) {} should generate an error
Message-ID: <483A9A2B.6020808@smart-websolutions.de>

p4raw-id: //depot/perl@34021

diff --git a/t/lib/warnings/toke b/t/lib/warnings/toke
index f4842a7..b82268d 100644 (file)
--- a/t/lib/warnings/toke
+++ b/t/lib/warnings/toke
@@ -852,3 +852,26 @@ use warnings 'deprecated';
 our $bar :unique;
 EXPECT
 Use of :unique is deprecated at - line 4.
+########
+# toke.c
+use warnings "syntax";
+sub proto_after_array(@$);
+sub proto_after_arref(\@$);
+sub proto_after_arref2(\[@$]);
+sub proto_after_arref3(\[@$]_);
+sub proto_after_hash(%$);
+sub proto_after_hashref(\%$);
+sub proto_after_hashref2(\[%$]);
+sub underscore_last_pos($_);
+sub underscore2($_;$);
+sub underscore_fail($_$);
+sub underscore_after_at(@_);
+no warnings "syntax";
+sub proto_after_array(@$);
+sub proto_after_hash(%$);
+sub underscore_fail($_$);
+EXPECT
+Prototype after '@' for main::proto_after_array : @$ at - line 3.
+Prototype after '%' for main::proto_after_hash : %$ at - line 7.
+Illegal character in prototype for main::underscore_fail : $_$ at - line 12.
+Prototype after '@' for main::underscore_after_at : @_ at - line 13.

diff --git a/toke.c b/toke.c
index b76e434..5f75233 100644 (file)
--- a/toke.c
+++ b/toke.c
@@ -6744,6 +6744,11 @@ Perl_yylex(pTHX)
                if (*s == '(') {
                    char *p;
                    bool bad_proto = FALSE;
+                   bool in_brackets = FALSE;
+                   char greedy_proto = ' ';
+                   bool proto_after_greedy_proto = FALSE;
+                   bool must_be_last = FALSE;
+                   bool underscore = FALSE;
                    const bool warnsyntax = ckWARN(WARN_SYNTAX);
 
                    s = scan_str(s,!!PL_madskills,FALSE);
@@ -6755,11 +6760,43 @@ Perl_yylex(pTHX)
                    for (p = d; *p; ++p) {
                        if (!isSPACE(*p)) {
                            d[tmp++] = *p;
-                           if (warnsyntax && !strchr("$@%*;[]&\\_", *p))
-                               bad_proto = TRUE;
+
+                           if (warnsyntax) {
+                               if (must_be_last)
+                                   proto_after_greedy_proto = TRUE;
+                               if (!strchr("$@%*;[]&\\_", *p)) {
+                                   bad_proto = TRUE;
+                               }
+                               else {
+                                   if ( underscore ) {
+                                       if ( *p != ';' )
+                                           bad_proto = TRUE;
+                                       underscore = FALSE;
+                                   }
+                                   if ( *p == '[' ) {
+                                       in_brackets = TRUE;
+                                   }
+                                   else if ( *p == ']' ) {
+                                       in_brackets = FALSE;
+                                   }
+                                   else if ( (*p == '@' || *p == '%') &&
+                                        ( tmp < 2 || d[tmp-2] != '\\' ) &&
+                                        !in_brackets ) {
+                                       must_be_last = TRUE;
+                                       greedy_proto = *p;
+                                   }
+                                   else if ( *p == '_' ) {
+                                       underscore = TRUE;
+                                   }
+                               }
+                           }
                        }
                    }
                    d[tmp] = '\0';
+                   if (proto_after_greedy_proto)
+                       Perl_warner(aTHX_ packWARN(WARN_SYNTAX),
+                                   "Prototype after '%c' for %"SVf" : %s",
+                                   greedy_proto, SVfARG(PL_subname), d);
                    if (bad_proto)
                        Perl_warner(aTHX_ packWARN(WARN_SYNTAX),
                                    "Illegal character in prototype for %"SVf" : %s",