Add unit test for RT #132008

Term::ReadLine generates empty &STDERR files

GH #1

Author: atoomic

dist/Term-ReadLine/lib/Term/ReadLine.pm

@@ -229,12 +229,17 @@ sub readline {
 }
 sub addhistory {}
 
+# used for testing purpose
+sub devtty { return '/dev/tty' }
+
 sub findConsole {
     my $console;
     my $consoleOUT;
 
-    if ($^O ne 'MSWin32' and -e "/dev/tty") {
-	$console = "/dev/tty";
+    my $devtty = devtty();
+
+    if ($^O ne 'MSWin32' and -e $devtty) {
+	$console = $devtty;
     } elsif ($^O eq 'MSWin32' or $^O eq 'msys' or -e "con") {
        $console = 'CONIN$';
        $consoleOUT = 'CONOUT$';
@@ -248,7 +253,7 @@ sub findConsole {
 
     $consoleOUT = $console unless defined $consoleOUT;
     $console = "&STDIN" unless defined $console;
-    if ($console eq "/dev/tty" && !open(my $fh, "<", $console)) {
+    if ($console eq $devtty && !open(my $fh, "<", $console)) {
       $console = "&STDIN";
       undef($consoleOUT);
     }
@@ -266,9 +271,6 @@ sub new {
   if (@_==2) {
     my($console, $consoleOUT) = $_[0]->findConsole;
 
-
-
-
     # the Windows CONIN$ needs GENERIC_WRITE mode to allow
     # a SetConsoleMode() if we end up using Term::ReadKey
     open FIN, (( $^O eq 'MSWin32' && $console eq 'CONIN$' ) ? '+<' : '<' ), $console;

dist/Term-ReadLine/t/ReadLine-STDERR.t

@@ -0,0 +1,41 @@
+#!./perl -w
+use strict;
+
+use Test::More;
+
+## unit test for RT 132008 - https://rt.perl.org/Ticket/Display.html?id=132008
+
+if ( $^O eq 'MSWin32' || !-e q{/dev/tty} ) {
+    plan skip_all => "Test not tested on windows or when /dev/tty do not exists";
+}
+else {
+    plan tests => 9;
+}
+
+if ( -e q[&STDERR] ) {
+    note q[Removing existing file &STDERR];
+    unlink q[&STDERR] or die q{Cannot remove existign file &STDERR [probably created from a previous run]};
+}
+
+use_ok('Term::ReadLine');
+can_ok( 'Term::ReadLine::Stub', qw{new devtty findConsole} );
+
+is( Term::ReadLine->devtty(), q{/dev/tty} );
+my @out = Term::ReadLine::Stub::findConsole();
+is_deeply \@out, [ q{/dev/tty}, q{/dev/tty} ], "findConsole is using /dev/tty";
+
+{
+    no warnings 'redefine';
+    my $donotexist = q[/this/should/not/exist/hopefully];
+
+    ok !-e $donotexist, "File $donotexist does not exist";
+    local *Term::ReadLine::Stub::devtty = sub { $donotexist };
+    is( Term::ReadLine->devtty(), $donotexist, "devtty mocked" );
+
+    my @out = Term::ReadLine::Stub::findConsole();
+    is_deeply \@out, [ q{&STDIN}, q{&STDERR} ], "findConsole is using /dev/tty" or diag explain \@out;
+
+    ok !-e q[&STDERR], 'file &STDERR do not exist before Term::ReadLine call';
+    my $tr = Term::ReadLine->new('whatever');
+    ok !-e q[&STDERR], 'file &STDERR was not created by mistake';
+}