Make like() and unlike() in t/test.pl refuse non-qr// arguments

As I noted in v5.21.1-12-g826af13 we have subtle bugs in the test suite
because you can do e.g. like($@, '') now which'll be a passing test even
when we have an error, because $@ =~ // will be true.

I'm just changing t/test.pl to not accept non-Regexp arguments, and
fixing up a bunch of test failures that resulted from that. There might
still be more of these in tests that I'm just not running, I've also
changed some of these from $str =~ /foo/ to $str eq 'foo'
(i.e. s/like/is/) in cases where that appeared to work, but it might
break some systems.

Let's just find that out via the smokers.

3 files changed, 7 insertions, 7 deletions

diff --git a/lib/charnames.t b/lib/charnames.t
index 5629f3a83c..bd0c21ea85 100644
--- a/lib/charnames.t
+++ b/lib/charnames.t
@@ -41,7 +41,7 @@ use charnames ":full";
 1
 EOE
 
-    like($@, "above 0xFF", "Verify get warning for \\N{above ff} under 'use bytes' with :full");
+    like($@, qr/above 0xFF/, "Verify get warning for \\N{above ff} under 'use bytes' with :full");
     ok(! defined $res, "... and result is undefined");
 
     $res = eval <<'EOE';
@@ -49,7 +49,7 @@ use charnames 'cyrillic';
 "Here: \N{Be}!";
 1
 EOE
-    like($@, "CYRILLIC CAPITAL LETTER BE.*above 0xFF", "Verify get warning under 'use bytes' with explicit script");
+    like($@, qr/CYRILLIC CAPITAL LETTER BE.*above 0xFF/, "Verify get warning under 'use bytes' with explicit script");
     ok(! defined $res, "... and result is undefined");
 
     $res = eval <<'EOE';
diff --git a/lib/overload.t b/lib/overload.t
index 7efd992fe8..d89ec2a510 100644
--- a/lib/overload.t
+++ b/lib/overload.t
@@ -305,7 +305,7 @@ is($na, '_!_xx_!_');
 $na = 0;
 
 $na = eval { ~$aI };
-like($@, '');
+is($@, '');
 
 bless \$x, OscalarI;
 
diff --git a/lib/perl5db.t b/lib/perl5db.t
index bd5615a673..0b777314fa 100644
--- a/lib/perl5db.t
+++ b/lib/perl5db.t
@@ -92,21 +92,21 @@ EOF
 {
     local $ENV{PERLDB_OPTS} = "ReadLine=0 NonStop=1";
     my $output = runperl(switches => [ '-d' ], stderr => 1, progfile => '../lib/perl5db/t/rt-66110');
-    like($output, "All tests successful.", "[perl #66110]");
+    like($output, qr/\bAll tests successful\.$/, "[perl #66110]");
 }
 # [ perl #116769] Frame=2
 {
     local $ENV{PERLDB_OPTS} = "frame=2 nonstop";
     my $output = runperl( switches => [ '-d' ], prog => 'print q{success}' );
     is( $?, 0, '[perl #116769] frame=2 does not crash debugger, exit == 0' );
-    like( $output, 'success' , '[perl #116769] code is run' );
+    is( $output, 'success' , '[perl #116769] code is run' );
 }
 # [ perl #116771] autotrace
 {
     local $ENV{PERLDB_OPTS} = "autotrace nonstop";
     my $output = runperl( switches => [ '-d' ], prog => 'print q{success}' );
     is( $?, 0, '[perl #116771] autotrace does not crash debugger, exit == 0' );
-    like( $output, 'success' , '[perl #116771] code is run' );
+    is( $output, 'success' , '[perl #116771] code is run' );
 }
 # [ perl #41461] Frame=2 noTTY
 {
@@ -114,7 +114,7 @@ EOF
     rc('');
     my $output = runperl( switches => [ '-d' ], prog => 'print q{success}' );
     is( $?, 0, '[perl #41461] frame=2 noTTY does not crash debugger, exit == 0' );
-    like( $output, 'success' , '[perl #41461] code is run' );
+    is( $output, 'success' , '[perl #41461] code is run' );
 }
 
 package DebugWrap;