fix: set $! to ENOENT on stat of non-existent mock (O::FC #13)

lib/Test/MockFile.pm

@@ -1036,8 +1036,14 @@ sub _mock_stat {
     # Find the path, following the symlink if required.
     my $file = _find_file_or_fh( $file_or_fh, $follow_link );
 
-    return [] if defined $file && defined BROKEN_SYMLINK   && $file eq BROKEN_SYMLINK;      # Allow an ELOOP to fall through here.
-    return [] if defined $file && defined CIRCULAR_SYMLINK && $file eq CIRCULAR_SYMLINK;    # Allow an ELOOP to fall through here.
+    if ( defined $file && defined BROKEN_SYMLINK && $file eq BROKEN_SYMLINK ) {
+        $! = ELOOP;
+        return 0;
+    }
+    if ( defined $file && defined CIRCULAR_SYMLINK && $file eq CIRCULAR_SYMLINK ) {
+        $! = ELOOP;
+        return 0;
+    }
 
     if ( !defined $file or !length $file ) {
         _real_file_access_hook( $type, [$file_or_fh] );
@@ -1051,7 +1057,10 @@ sub _mock_stat {
     }
 
     # File is not present so no stats for you!
-    return [] if !$file_data->is_link && !defined $file_data->contents();
+    if ( !$file_data->is_link && !defined $file_data->contents() ) {
+        $! = ENOENT;
+        return 0;
+    }
 
     # Make sure the file size is correct in the stats before returning its contents.
     return [ $file_data->stat ];

t/enoent_on_nonexistent.t

@@ -0,0 +1,106 @@
+#!/usr/bin/perl -w
+
+# Regression test for Overload::FileCheck GH#13
+# When a file is mocked as non-existent (undef contents),
+# -e should set $! to ENOENT, not EBADF.
+
+use strict;
+use warnings;
+
+use Test2::Bundle::Extended;
+use Test2::Tools::Explain;
+use Test2::Plugin::NoWarnings;
+
+use Errno qw/ENOENT EBADF/;
+
+use Test::MockFile;
+
+subtest '-e on non-existent mock sets ENOENT' => sub {
+    my $path = '/some/nonexistent/path';
+    my $mock = Test::MockFile->file( $path, undef );
+
+    $! = 0;
+    my $exists = -e $path;
+
+    ok( !$exists, '-e returns false for file mocked with undef contents' );
+    is( $! + 0, ENOENT, '$! is ENOENT (not EBADF) after -e on non-existent mock' );
+};
+
+subtest '-e on non-existent mock (no content arg)' => sub {
+    my $path = '/another/missing/file';
+    my $mock = Test::MockFile->file($path);
+
+    $! = 0;
+    my $exists = -e $path;
+
+    ok( !$exists, '-e returns false for file mocked without content' );
+    is( $! + 0, ENOENT, '$! is ENOENT after -e on file mocked without content' );
+};
+
+subtest '-f on non-existent mock sets ENOENT' => sub {
+    my $path = '/mock/not/a/file';
+    my $mock = Test::MockFile->file( $path, undef );
+
+    $! = 0;
+    my $is_file = -f $path;
+
+    ok( !$is_file, '-f returns false for file mocked with undef contents' );
+    is( $! + 0, ENOENT, '$! is ENOENT after -f on non-existent mock' );
+};
+
+subtest '-d on non-existent mock sets ENOENT' => sub {
+    my $path = '/mock/not/a/dir';
+    my $mock = Test::MockFile->dir($path);
+
+    $! = 0;
+    my $is_dir = -d $path;
+
+    ok( !$is_dir, '-d returns false for non-existent dir mock' );
+    is( $! + 0, ENOENT, '$! is ENOENT after -d on non-existent dir mock' );
+};
+
+subtest 'stat on non-existent mock fails cleanly' => sub {
+    my $path = '/mock/no/stat';
+    my $mock = Test::MockFile->file( $path, undef );
+
+    $! = 0;
+    my @st = stat($path);
+
+    is( scalar @st, 0, 'stat returns empty list for non-existent mock' );
+
+    # errno after stat() on non-existent mock depends on Overload::FileCheck's XS
+    # cleanup behavior. The _check() Perl code sets ENOENT correctly, but the XS
+    # FREETMPS/LEAVE in _overload_ft_stat() may clobber errno before returning.
+    # File checks (-e, -f, etc.) are unaffected because _check_from_stat checks
+    # array length rather than errno. See cpanel/Overload-FileCheck for the fix.
+    todo 'Overload::FileCheck XS clobbers errno on stat failure path' => sub {
+        is( $! + 0, ENOENT, '$! is ENOENT after stat on non-existent mock' );
+    };
+};
+
+subtest 'lstat on non-existent mock fails cleanly' => sub {
+    my $path = '/mock/no/lstat';
+    my $mock = Test::MockFile->file( $path, undef );
+
+    $! = 0;
+    my @st = lstat($path);
+
+    is( scalar @st, 0, 'lstat returns empty list for non-existent mock' );
+
+    todo 'Overload::FileCheck XS clobbers errno on stat failure path' => sub {
+        is( $! + 0, ENOENT, '$! is ENOENT after lstat on non-existent mock' );
+    };
+};
+
+subtest '-e succeeds for existing mock' => sub {
+    my $path = '/mock/exists';
+    my $mock = Test::MockFile->file( $path, 'content' );
+
+    $! = 0;
+    my $exists = -e $path;
+
+    ok( $exists, '-e returns true for file mocked with content' );
+    is( $! + 0, 0, '$! is not set after successful -e' );
+};
+
+done_testing();

t/mock_stat.t

@@ -9,7 +9,7 @@ use Test2::Plugin::NoWarnings;
 
 use Test::MockFile qw< nostrict >;
 use Overload::FileCheck qw/:check/;
-use Errno qw/ELOOP/;
+use Errno qw/ELOOP ENOENT/;
 
 use Cwd ();
 
@@ -97,11 +97,12 @@ my $basic_stat_return = array {
 };
 
 is( Test::MockFile::_mock_stat( 'lstat', '/foo/bar' ), $basic_stat_return, "/foo/bar mock stat" );
-is( Test::MockFile::_mock_stat( 'stat',  '/aaa' ),     [],                 "/aaa mock stat when looped." );
+is( Test::MockFile::_mock_stat( 'stat',  '/aaa' ),     0,                  "/aaa mock stat when looped." );
 is( $! + 0, ELOOP, "Throws an ELOOP error" );
 
 push @mocked_files, Test::MockFile->file('/foo/baz');    # Missing file but mocked.
-is( Test::MockFile::_mock_stat( 'lstat', '/foo/baz' ), [], "/foo/baz mock stat when missing." );
+is( Test::MockFile::_mock_stat( 'lstat', '/foo/baz' ), 0, "/foo/baz mock stat when missing." );
+is( $! + 0, ENOENT, "Throws an ENOENT error for missing file" );
 
 my $symlink_lstat_return = array {
     item 0;
@@ -120,7 +121,7 @@ my $symlink_lstat_return = array {
 };
 
 is( Test::MockFile::_mock_stat( 'lstat', '/broken_link' ), $symlink_lstat_return, "lstat on /broken_link returns the stat on the symlink itself." );
-is( Test::MockFile::_mock_stat( 'stat',  '/broken_link' ), [],                    "stat on /broken_link is an empty array since what it points to doesn't exist." );
+is( Test::MockFile::_mock_stat( 'stat',  '/broken_link' ), 0,                     "stat on /broken_link returns 0 since what it points to doesn't exist." );
 
 {
     my $exe = q[/tmp/custom.exe];