Make C<undef ~~ 0> and C<undef ~~ ""> not match (like in 5.10.0)

This makes ~~ commutative with regard to undef, and fixes an
inconsistency, since C<undef ~~ [0]> was not matching, and ~~
should be distributive in this case.

diff --git a/pod/perlsyn.pod b/pod/perlsyn.pod
index 2ba30d8..9212573 100644 (file)
--- a/pod/perlsyn.pod
+++ b/pod/perlsyn.pod
@@ -720,6 +720,7 @@ and "Array" entries apply in those cases. (For blessed references, the
     Object  Any       invokes ~~ overloading on $object, or falls back:
     Any     Num       numeric equality         $a == $b
     Num     numish[4] numeric equality         $a == $b
+    undef   Any       undefined                !defined($b)
     Any     Any       string equality          $a eq $b
 
  1 - empty hashes or arrays will match.

diff --git a/pp_ctl.c b/pp_ctl.c
index 6bb5b40..59ac8c1 100644 (file)
--- a/pp_ctl.c
+++ b/pp_ctl.c
@@ -4393,6 +4393,10 @@ S_do_smartmatch(pTHX_ HV *seen_this, HV *seen_other)
        SP -= 2;
        goto sm_any_scalar;
     }
+    else if (!SvOK(d)) {
+       /* undef ~~ scalar ; we already know that the scalar is SvOK */
+       RETPUSHNO;
+    }
     else
   sm_any_scalar:
     if (SvNIOK(e) || (SvPOK(e) && looks_like_number(e) && SvNIOK(d))) {

diff --git a/t/op/smartmatch.t b/t/op/smartmatch.t
index 58466af..cb0e656 100644 (file)
--- a/t/op/smartmatch.t
+++ b/t/op/smartmatch.t
@@ -70,7 +70,7 @@ my %keyandmore = map { $_ => 0 } @keyandmore;
 my %fooormore = map { $_ => 0 } @fooormore;
 
 # Load and run the tests
-plan tests => 314;
+plan tests => 322;
 
 while (<DATA>) {
     next if /^#/ || !/\S/;
@@ -371,7 +371,7 @@ __DATA__
        ["foo", "bar"]          [["foo"], ["bar"]]
 !      ["foo", "bar"]          [qr/o/, "foo"]
        ["foo", undef, "bar"]   [qr/o/, undef, "bar"]
-       ["foo", undef, "bar"]   [qr/o/, "",    "bar"]
+!      ["foo", undef, "bar"]   [qr/o/, "",    "bar"]
 !      ["foo", "", "bar"]      [qr/o/, undef, "bar"]
        $deep1                  $deep1
        @$deep1                 @$deep1
@@ -409,6 +409,11 @@ __DATA__
 !      undef           [1, 2, [undef], 4]
 !      undef           @fooormore
        undef           @sparse
+       undef           [undef]
+!      0               [undef]
+!      ""              [undef]
+!      undef           [0]
+!      undef           [""]
 
 # - nested arrays and ~~ distributivity
        11              [[11]]
@@ -422,7 +427,8 @@ __DATA__
 !      2               3
        0               FALSE
        3-2             TRUE
-       undef           0
+!      undef           0
+!      (my $u)         0
 
 # Number against string
 =      2               "2"
@@ -430,6 +436,8 @@ __DATA__
 !      2               "2bananas"
 !=     2_3             "2_3"           NOWARNINGS
        FALSE           "0"
+!      undef           "0"
+!      undef           ""
 
 # Regex against string
        "x"             qr/x/

diff --git a/t/op/switch.t b/t/op/switch.t
index d8cb781..2012c6c 100644 (file)
--- a/t/op/switch.t
+++ b/t/op/switch.t
@@ -133,15 +133,15 @@ sub check_outside1 { is($_, "outside", "\$_ lexically scoped") }
 }
 {
     no warnings "uninitialized";
-    my $ok = 0;
-    given (undef) { when(0) {$ok = 1} }
+    my $ok = 1;
+    given (undef) { when(0) {$ok = 0} }
     is($ok, 1, "Given(undef) when(0)");
 }
 {
     no warnings "uninitialized";
     my $undef;
-    my $ok = 0;
-    given ($undef) { when(0) {$ok = 1} }
+    my $ok = 1;
+    given ($undef) { when(0) {$ok = 0} }
     is($ok, 1, 'Given($undef) when(0)');
 }
 ########
@@ -158,15 +158,15 @@ sub check_outside1 { is($_, "outside", "\$_ lexically scoped") }
 }
 {
     no warnings "uninitialized";
-    my $ok = 0;
-    given (undef) { when("") {$ok = 1} }
+    my $ok = 1;
+    given (undef) { when("") {$ok = 0} }
     is($ok, 1, 'Given(undef) when("")');
 }
 {
     no warnings "uninitialized";
     my $undef;
-    my $ok = 0;
-    given ($undef) { when("") {$ok = 1} }
+    my $ok = 1;
+    given ($undef) { when("") {$ok = 0} }
     is($ok, 1, 'Given($undef) when("")');
 }
 ########