From: Vincent Pit <vince@profvince.com>
Date: Wed, 25 Feb 2009 10:33:50 +0000 (+0100)
Subject: Make the package and method names passed to callbacks readonly
X-Git-Tag: v0.02~4
X-Git-Url: http://git.vpit.fr/?p=perl%2Fmodules%2FLexical-Types.git;a=commitdiff_plain;h=09c7a37f3be8034a8c04c2011208724e04441d83

Make the package and method names passed to callbacks readonly
---

diff --git a/MANIFEST b/MANIFEST
index 0d80d12..d556b64 100644
--- a/MANIFEST
+++ b/MANIFEST
@@ -10,6 +10,7 @@ t/00-load.t
 t/10-args.t
 t/11-integrate.t
 t/12-padsv.t
+t/13-ro.t
 t/20-object.t
 t/21-tie.t
 t/22-magic.t
diff --git a/Types.xs b/Types.xs
index 9baa8da..2e8bda4 100644
--- a/Types.xs
+++ b/Types.xs
@@ -121,9 +121,9 @@ STATIC OP *lt_pp_padsv(pTHX) {
 
    PUSHMARK(SP);
    EXTEND(SP, 3);
-   PUSHs(sv_2mortal(newSVsv(oi->type_pkg)));
+   PUSHs(oi->type_pkg);
    PUSHs(sv);
-   PUSHs(sv_2mortal(newSVsv(oi->orig_pkg)));
+   PUSHs(oi->orig_pkg);
    PUTBACK;
 
    items = call_sv(oi->type_meth, G_ARRAY | G_METHOD);
@@ -160,7 +160,7 @@ STATIC OP *lt_pp_padsv(pTHX) {
  * pp_padsv, but much less than if we would have set PL_ppaddr[OP_PADSV]
  * globally. */
 
-STATIC U32 lt_TYPEDSCALAR_hash = 0; 
+STATIC SV *lt_default_meth = NULL;
 
 STATIC OP *(*lt_old_ck_padany)(pTHX_ OP *) = 0;
 
@@ -175,13 +175,12 @@ STATIC OP *lt_ck_padany(pTHX_ OP *o) {
  stash = PL_in_my_stash;
  if (stash && (hint = lt_hint())) {
   SV *orig_pkg  = newSVpvn(HvNAME_get(stash), HvNAMELEN_get(stash));
-  SV *orig_meth = newSVpvn_share("TYPEDSCALAR", 11, lt_TYPEDSCALAR_hash);
+  SV *orig_meth = lt_default_meth;
   SV *type_pkg  = orig_pkg;
   SV *type_meth = orig_meth;
   SV *code      = INT2PTR(SV *, SvUVX(hint));
 
   SvREADONLY_on(orig_pkg);
-  SvREADONLY_on(orig_meth);
 
   if (code) {
    int items;
@@ -209,12 +208,16 @@ STATIC OP *lt_ck_padany(pTHX_ OP *o) {
     SV *rsv;
     if (items > 1) {
      rsv = POPs;
-     if (SvOK(rsv))
+     if (SvOK(rsv)) {
       type_meth = newSVsv(rsv);
+      SvREADONLY_on(type_meth);
+     }
     }
     rsv = POPs;
-    if (SvOK(rsv))
+    if (SvOK(rsv)) {
      type_pkg = newSVsv(rsv);
+     SvREADONLY_on(type_pkg);
+    }
    }
    PUTBACK;
 
@@ -222,8 +225,11 @@ STATIC OP *lt_ck_padany(pTHX_ OP *o) {
    LEAVE;
   }
 
-  lt_old_pp_padsv     = PL_ppaddr[OP_PADSV];
+  if (type_meth == orig_meth)
+   SvREFCNT_inc(orig_meth);
   lt_map_store(o, orig_pkg, type_pkg, type_meth, lt_old_pp_padsv);
+
+  lt_old_pp_padsv     = PL_ppaddr[OP_PADSV];
   PL_ppaddr[OP_PADSV] = lt_pp_padsv;
  }
 
@@ -249,7 +255,8 @@ PROTOTYPES: DISABLE
 BOOT: 
 {                                    
  if (!lt_initialized++) {
-  PERL_HASH(lt_TYPEDSCALAR_hash, "TYPEDSCALAR", 11);
+  lt_default_meth = newSVpvn("TYPEDSCALAR", 11);
+  SvREADONLY_on(lt_default_meth);
 
   PERL_HASH(lt_hash, __PACKAGE__, __PACKAGE_LEN__);
   lt_op_map = newHV();
diff --git a/t/13-ro.t b/t/13-ro.t
new file mode 100644
index 0000000..c8e9f7d
--- /dev/null
+++ b/t/13-ro.t
@@ -0,0 +1,67 @@
+#!perl -T
+
+use strict;
+use warnings;
+
+use Test::More tests => 4;
+
+sub Str::TYPEDSCALAR { }
+
+sub Str1::TYPEDSCALAR {
+ $_[0] = 'dongs';
+ ();
+}
+
+sub Str2::TYPEDSCALAR {
+ $_[2] = 'hlagh';
+ ();
+}
+
+sub ro_re {
+ my ($file, $line) = map quotemeta, @_;
+ $file = '\\(eval \\d+\\)' unless $file;
+ return qr/^Modification of a read-only value attempted at $file line $line/;
+}
+
+sub maybe_warn {
+ diag 'This will throw two warnings' if $] >= 5.008008 and $] < 5.009;
+}
+
+{
+ maybe_warn();
+ local $@;
+ eval q!
+  use Lexical::Types as => sub { $_[0] = 'dongs'; () };
+  my Str $x;
+ !;
+ like $@, ro_re('', 2), '$_[0] in initializer is read only';
+}
+
+SKIP: {
+ skip 'Kinda broken on old 5.8.x' => 1 if $] <= 5.008006;
+ maybe_warn();
+ local $@;
+ eval q!
+  use Lexical::Types as => sub { $_[1] = 'hlagh'; () };
+  my Str $x;
+ !;
+ like $@, ro_re('', 2), '$_[1] in initializer is read only';
+}
+
+{
+ local $@;
+ eval q[
+  use Lexical::Types;
+  my Str1 $x;
+ ];
+ like $@, ro_re($0, 11), '$_[0] in initializer is read only';
+}
+
+{
+ local $@;
+ eval q[
+  use Lexical::Types;
+  my Str2 $x;
+ ];
+ like $@, ro_re($0, 16), '$_[2] in initializer is read only';
+}