Re: [perl #43357] *DESTROY = sub {} at runtime

From: "Brandon Black" <blblack@gmail.com>
Message-ID: <84621a60706270807r7af65546x8d959b131ffa28e6@mail.gmail.com>

p4raw-id: //depot/perl@31489

1 files changed, 45 insertions, 1 deletions

diff --git a/t/mro/basic.t b/t/mro/basic.t
index 332782e02b..be7e3ddec0 100644
--- a/t/mro/basic.t
+++ b/t/mro/basic.t
@@ -3,7 +3,7 @@
 use strict;
 use warnings;
 
-require q(./test.pl); plan(tests => 21);
+require q(./test.pl); plan(tests => 27);
 
 {
     package MRO_A;
@@ -127,6 +127,8 @@ is(eval { MRO_N->testfunc() }, 123);
 }
 
 # clearing @ISA in different ways
+#  some are destructive to the package, hence the new
+#  package name each time
 {
     no warnings 'uninitialized';
     {
@@ -141,6 +143,48 @@ is(eval { MRO_N->testfunc() }, 123);
     $ISACLEAR::ISA[1] = undef;
     ok(eq_array(mro::get_linear_isa('ISACLEAR'),[qw/ISACLEAR XX main ZZ/]));
 
+    # undef the array itself
     undef @ISACLEAR::ISA;
     ok(eq_array(mro::get_linear_isa('ISACLEAR'),[qw/ISACLEAR/]));
 }
+
+{
+    {
+        package ISACLEAR2;
+        our @ISA = qw/XX YY ZZ/;
+    }
+
+    # baseline
+    ok(eq_array(mro::get_linear_isa('ISACLEAR2'),[qw/ISACLEAR2 XX YY ZZ/]));
+
+    # delete @ISA
+    delete $ISACLEAR2::{ISA};
+    ok(eq_array(mro::get_linear_isa('ISACLEAR2'),[qw/ISACLEAR2/]));
+}
+
+# another destructive test, undef the ISA glob
+{
+    {
+        package ISACLEAR3;
+        our @ISA = qw/XX YY ZZ/;
+    }
+    # baseline
+    ok(eq_array(mro::get_linear_isa('ISACLEAR3'),[qw/ISACLEAR3 XX YY ZZ/]));
+
+    undef *ISACLEAR3::ISA;
+    ok(eq_array(mro::get_linear_isa('ISACLEAR3'),[qw/ISACLEAR3/]));
+}
+
+# This is how Class::Inner does it
+{
+    {
+        package ISACLEAR4;
+        our @ISA = qw/XX YY ZZ/;
+    }
+    # baseline
+    ok(eq_array(mro::get_linear_isa('ISACLEAR4'),[qw/ISACLEAR4 XX YY ZZ/]));
+
+    delete $ISACLEAR4::{ISA};
+    delete $::{ISACLEAR4::};
+    ok(eq_array(mro::get_linear_isa('ISACLEAR4'),[qw/ISACLEAR4/]));
+}