Work on eliminating systematic failures on make minitest:

make minitest passes a -minitest flag to t/TEST
t/TEST sees this and sets $ENV{PERL_CORE_MINITEST}
Tests can choose to skip based on this.
(Other tactic is to make loading of Errno by %! happen at run time.)

p4raw-id: //depot/perl@22423

6 files changed, 21 insertions, 9 deletions

diff --git a/t/io/binmode.t b/t/io/binmode.t
index f50d0f7fa8..be198ae645 100644
--- a/t/io/binmode.t
+++ b/t/io/binmode.t
@@ -7,8 +7,9 @@ BEGIN {
 }
 
 use Config;
-use Errno;
-
+BEGIN {
+    eval {require Errno; Errno->import;};
+}
 plan(tests => 9);
 
 ok( binmode(STDERR),            'STDERR made binary' );
@@ -31,6 +32,7 @@ ok( binmode(STDOUT, ":raw"),    '  raw' );
 ok( binmode(STDOUT, ":crlf"),   '  and crlf' );
 
 SKIP: {
+    skip "minitest", 1 if $ENV{PERL_CORE_MINITEST};
     skip "no EBADF", 1 if (!exists &Errno::EBADF);
 
     no warnings 'io';
diff --git a/t/io/crlf.t b/t/io/crlf.t
index 2ee7b83191..d6f3fc3925 100644
--- a/t/io/crlf.t
+++ b/t/io/crlf.t
@@ -32,9 +32,9 @@ if (find PerlIO::Layer 'perlio') {
 
  SKIP:
  {
-  eval 'use PerlIO::scalar';
-  skip(q/miniperl cannnot load PerlIO::scalar/)
-      if $@ =~ /dynamic loading not available/;
+  skip("miniperl can't rely on loading PerlIO::scalar")
+      if $ENV{PERL_CORE_MINITEST};
+  eval 'PerlIO::scalar';
   my $fcontents = join "", map {"$_\015\012"} "a".."zzz";
   open my $fh, "<:crlf", \$fcontents;
   local $/ = "xxx";
diff --git a/t/io/layers.t b/t/io/layers.t
index 904ef93fa2..d0e37a3c8d 100644
--- a/t/io/layers.t
+++ b/t/io/layers.t
@@ -44,8 +44,10 @@ print <<__EOH__;
 __EOH__
 
 SKIP: {
+    # FIXME - more of these could be tested without Encode or full perl
     skip("This perl does not have Encode", $NTEST)
 	unless " $Config{extensions} " =~ / Encode /;
+    skip("miniperl does not have Encode", $NTEST) if $ENV{PERL_CORE_MINITEST};
 
     sub check {
 	my ($result, $expected, $id) = @_;
diff --git a/t/io/open.t b/t/io/open.t
index e71d2ec3c5..82ac2f3aaa 100755
--- a/t/io/open.t
+++ b/t/io/open.t
@@ -239,10 +239,14 @@ like( $@, qr/Bad filehandle:\s+afile/,          '       right error' );
 
 SKIP: {
     skip "This perl uses perlio", 1 if $Config{useperlio};
-    skip "This system doesn't understand EINVAL", 1 unless exists $!{EINVAL};
+    skip "miniperl cannot be relied on to load %Errno"
+	if $ENV{PERL_CORE_MINITEST};
+    # Force the reference to %! to be run time by writing ! as {"!"}
+    skip "This system doesn't understand EINVAL", 1
+	unless exists ${"!"}{EINVAL};
 
     no warnings 'io';
-    ok( !open(F,'>',\my $s) && $!{EINVAL}, 'open(reference) raises EINVAL' );
+    ok(!open(F,'>',\my $s) && ${"!"}{EINVAL}, 'open(reference) raises EINVAL');
 }
 
 {
diff --git a/t/io/print.t b/t/io/print.t
index f33aa666a3..31d559aac9 100755
--- a/t/io/print.t
+++ b/t/io/print.t
@@ -6,7 +6,8 @@ BEGIN {
 }
 
 use strict 'vars';
-use Errno;
+eval 'use Errno';
+die $@ if $@ and !$ENV{PERL_CORE_MINITEST};
 
 print "1..19\n";
 
@@ -41,6 +42,8 @@ print @x,"14\nok",@y;
     print "";
 }
 
+$\ = '';
+
 if (!exists &Errno::EBADF) {
     print "ok 19 # skipped: no EBADF\n";
 } else {
diff --git a/t/io/read.t b/t/io/read.t
index ea2672dedb..63ffee1d5a 100755
--- a/t/io/read.t
+++ b/t/io/read.t
@@ -9,7 +9,8 @@ BEGIN {
 }
 
 use strict;
-use Errno;
+eval 'use Errno';
+die $@ if $@ and !$ENV{PERL_CORE_MINITEST};
 
 plan tests => 2;