1 files changed, 73 insertions, 0 deletions
diff --git a/t/unit_run_test_harness.t b/t/unit_run_test_harness.t
new file mode 100644
index 0000000..e6a7f53
--- /dev/null
+++ b/t/unit_run_test_harness.t
@@ -0,0 +1,73 @@
+#!/usr/bin/perl -w
+
+use strict;
+use lib 't/lib';
+use MBTest tests => 9;
+
+blib_load('Module::Build');
+
+my $tmp = MBTest->tmpdir;
+
+use DistGen;
+my $dist = DistGen->new( dir => $tmp );
+$dist->regen;
+
+$dist->chdir_in;
+
+#########################
+
+
+# make sure Test::Harness loaded before we define Test::Harness::runtests otherwise we'll
+# get another redefined warning inside Test::Harness::runtests
+use Test::Harness;
+
+{
+  package MB::Subclass;
+  use base qw(Module::Build);
+  sub harness_switches { return }
+}
+
+{
+  local $SIG{__WARN__} = sub { die "Termination after a warning: $_[0]"};
+  my $mock1 = { A => 1 };
+  my $mock2 = { B => 2 };
+
+  no warnings qw[redefine once];
+
+  # This runs run_test_harness with Test::Harness::switches = undef and harness_switches() returning empty list,
+  # ensure there are no warnings, and output is empty too
+  {
+    my $mb = MB::Subclass->new( module_name => $dist->name );
+    local *Test::Harness::runtests = sub {
+      is shift(), $mock1, "runtests ran with expected parameters";
+      is shift(), $mock2, "runtests ran with expected parameters";
+      is $Test::Harness::switches, '', "switches are undef";
+      is $Test::Harness::Switches, '', "switches are undef";
+    };
+
+    # $Test::Harness::switches and $Test::Harness::switches are aliases, but we pretend we don't know this
+    local $Test::Harness::switches = '';
+    local $Test::Harness::switches = '';
+    $mb->run_test_harness([$mock1, $mock2]);
+
+    ok 1, "run_test_harness should not produce warning if Test::Harness::[Ss]witches are undef and harness_switches() return empty list";
+  }
+
+  # This runs run_test_harness with Test::Harness::switches = '' and harness_switches() returning empty list,
+  # ensure there are no warnings, and switches are empty string
+  {
+    my $mb = MB::Subclass->new( module_name => $dist->name );
+    local *Test::Harness::runtests = sub {
+      is shift(), $mock1, "runtests ran with expected parameters";
+      is shift(), $mock2, "runtests ran with expected parameters";
+      is $Test::Harness::switches, '', "switches are empty string";
+      is $Test::Harness::Switches, '', "switches are empty string";
+    };
+
+    # $Test::Harness::switches and $Test::Harness::switches are aliases, but we pretend we don't know this
+    local $Test::Harness::switches = '';
+    local $Test::Harness::switches = '';
+    $mb->run_test_harness([$mock1, $mock2]);
+  }
+
+}