Fix the syswrite downgrade bug of

[perl5.git] / t / io / layers.t

diff --git a/t/io/layers.t b/t/io/layers.t
index 0da804c..904ef93 100644 (file)
--- a/t/io/layers.t
+++ b/t/io/layers.t
@@ -1,5 +1,7 @@
 #!./perl
 
+my $PERLIO;
+
 BEGIN {
     chdir 't' if -d 't';
     @INC = '../lib';
@@ -8,37 +10,86 @@ BEGIN {
        print "1..0 # Skip: not perlio\n";
        exit 0;
     }
+    eval 'use Encode';
+    if ($@ =~ /dynamic loading not available/) {
+        print "1..0 # miniperl cannot load Encode\n";
+       exit 0;
+    }
+    # Makes testing easier.
+    $ENV{PERLIO} = 'stdio' if exists $ENV{PERLIO} && $ENV{PERLIO} eq '';
     if (exists $ENV{PERLIO} && $ENV{PERLIO} !~ /^(stdio|perlio|mmap)$/) {
+       # We are not prepared for anything else.
        print "1..0 # PERLIO='$ENV{PERLIO}' unknown\n";
        exit 0;
     }
+    $PERLIO = exists $ENV{PERLIO} ? $ENV{PERLIO} : "(undef)";
 }
 
-plan tests => 43;
-
 use Config;
 
-my $DOSISH   = $^O =~ /^(?:MSWin32|cygwin|os2|dos|NetWare|mint)$/;
-my $NONSTDIO = exists $ENV{PERLIO} && $ENV{PERLIO} ne 'stdio';
+my $DOSISH    = $^O =~ /^(?:MSWin32|os2|dos|NetWare|mint)$/ ? 1 : 0;
+   $DOSISH    = 1 if !$DOSISH and $^O =~ /^uwin/;
+my $NONSTDIO  = exists $ENV{PERLIO} && $ENV{PERLIO} ne 'stdio'     ? 1 : 0;
+my $FASTSTDIO = $Config{d_faststdio} && $Config{usefaststdio}      ? 1 : 0;
+
+my $NTEST = 43 - (($DOSISH || !$FASTSTDIO) ? 7 : 0) - ($DOSISH ? 5 : 0);
+
+plan tests => $NTEST;
+
+print <<__EOH__;
+# PERLIO    = $PERLIO
+# DOSISH    = $DOSISH
+# NONSTDIO  = $NONSTDIO
+# FASTSTDIO = $FASTSTDIO
+__EOH__
 
 SKIP: {
-    skip("This perl does not have Encode", 43)
+    skip("This perl does not have Encode", $NTEST)
        unless " $Config{extensions} " =~ / Encode /;
 
     sub check {
        my ($result, $expected, $id) = @_;
+       # An interesting dance follows where we try to make the following
+       # IO layer stack setups to compare equal:
+       #
+       # PERLIO     UNIX-like                   DOS-like
+       #
+       # unset / "" unix perlio / stdio [1]     unix crlf
+       # stdio      unix perlio / stdio [1]     stdio
+       # perlio     unix perlio                 unix perlio
+       # mmap       unix mmap                   unix mmap
+       #
+       # [1] "stdio" if Configure found out how to do "fast stdio" (depends
+       # on the stdio implementation) and in Perl 5.8, otherwise "unix perlio"
+       #
        if ($NONSTDIO) {
            # Get rid of "unix".
            shift @$result if $result->[0] eq "unix";
            # Change expectations.
-           $expected->[0] = $ENV{PERLIO} if $expected->[0] eq "stdio";
+           if ($FASTSTDIO) {
+               $expected->[0] = $ENV{PERLIO};
+           } else {
+               $expected->[0] = $ENV{PERLIO} if $expected->[0] eq "stdio";
+           }
+       } elsif (!$FASTSTDIO && !$DOSISH) {
+           splice(@$result, 0, 2, "stdio")
+               if @$result >= 2 &&
+                  $result->[0] eq "unix" &&
+                  $result->[1] eq "perlio";
        } elsif ($DOSISH) {
            splice(@$result, 0, 2, "stdio")
-               if $result->[0] eq "unix" &&
+               if @$result >= 2 &&
+                  $result->[0] eq "unix" &&
                   $result->[1] eq "crlf";
        }
+       if ($DOSISH && grep { $_ eq 'crlf' } @$expected) {
+           # 5 tests potentially skipped because
+           # DOSISH systems already have a CRLF layer
+           # which will make new ones not stick.
+           @$expected = grep { $_ ne 'crlf' } @$expected;
+       }
        my $n = scalar @$expected;
-       is($n, scalar @$expected, "$id - layers = $n");
+       is($n, scalar @$expected, "$id - layers == $n");
        for (my $i = 0; $i < $n; $i++) {
            my $j = $expected->[$i];
            if (ref $j eq 'CODE') {
@@ -79,7 +130,6 @@ SKIP: {
          [ "stdio" ],
          ":raw");
 
-    binmode(F, ":pop") if $DOSISH; # Drop one extra :crlf.
     binmode(F, ":utf8");
 
     check([ PerlIO::get_layers(F) ],
@@ -106,9 +156,8 @@ SKIP: {
 
     binmode(F, ":raw :encoding(latin1)"); # "latin1" will be canonized
 
-    SKIP: {
-       skip("too complex layer coreography", 7) if $DOSISH;
-
+    # 7 tests potentially skipped.
+    unless ($DOSISH || !$FASTSTDIO) {
        my @results = PerlIO::get_layers(F, details => 1);
 
        # Get rid of the args and the flags.