3 files changed, 36 insertions, 13 deletions
diff --git a/test/io/wait/test_io_wait.rb b/test/io/wait/test_io_wait.rb
index 6b4722e1be..cbc01f9622 100644
--- a/test/io/wait/test_io_wait.rb
+++ b/test/io/wait/test_io_wait.rb
@@ -3,10 +3,9 @@
 require 'test/unit'
 require 'timeout'
 require 'socket'
-begin
-  require 'io/wait'
-rescue LoadError
-end
+
+# For `IO#ready?` and `IO#nread`:
+require 'io/wait'
 
 class TestIOWait < Test::Unit::TestCase
 
@@ -37,6 +36,7 @@ class TestIOWait < Test::Unit::TestCase
   end
 
   def test_ready?
+    omit 'unstable on MinGW' if /mingw/ =~ RUBY_PLATFORM
     assert_not_predicate @r, :ready?, "shouldn't ready, but ready"
     @w.syswrite "."
     sleep 0.1
@@ -50,6 +50,7 @@ class TestIOWait < Test::Unit::TestCase
   end
 
   def test_wait
+    omit 'unstable on MinGW' if /mingw/ =~ RUBY_PLATFORM
     assert_nil @r.wait(0)
     @w.syswrite "."
     sleep 0.1
@@ -161,6 +162,34 @@ class TestIOWait < Test::Unit::TestCase
     assert_equal @w, @w.wait(0.01, :read_write)
   end
 
+  def test_wait_mask_writable
+    omit("Missing IO::WRITABLE!") unless IO.const_defined?(:WRITABLE)
+    assert_equal IO::WRITABLE, @w.wait(IO::WRITABLE, 0)
+  end
+
+  def test_wait_mask_readable
+    omit("Missing IO::READABLE!") unless IO.const_defined?(:READABLE)
+    @w.write("Hello World\n" * 3)
+    assert_equal IO::READABLE, @r.wait(IO::READABLE, 0)
+
+    @r.gets
+    assert_equal IO::READABLE, @r.wait(IO::READABLE, 0)
+  end
+
+  def test_wait_mask_zero
+    omit("Missing IO::WRITABLE!") unless IO.const_defined?(:WRITABLE)
+    assert_raise(ArgumentError) do
+      @w.wait(0, 0)
+    end
+  end
+
+  def test_wait_mask_negative
+    omit("Missing IO::WRITABLE!") unless IO.const_defined?(:WRITABLE)
+    assert_raise(ArgumentError) do
+      @w.wait(-6, 0)
+    end
+  end
+
 private
 
   def fill_pipe
diff --git a/test/io/wait/test_io_wait_uncommon.rb b/test/io/wait/test_io_wait_uncommon.rb
index b6f1c29bcd..0f922f4e24 100644
--- a/test/io/wait/test_io_wait_uncommon.rb
+++ b/test/io/wait/test_io_wait_uncommon.rb
@@ -1,6 +1,5 @@
 # frozen_string_literal: true
 require 'test/unit'
-require 'io/wait'
 
 # test uncommon device types to check portability problems
 # We may optimize IO#wait_*able for non-Linux kernels in the future
@@ -13,7 +12,7 @@ class TestIOWaitUncommon < Test::Unit::TestCase
   end
 
   def test_fifo_wait
-    skip 'no mkfifo' unless File.respond_to?(:mkfifo) && IO.const_defined?(:NONBLOCK)
+    omit 'no mkfifo' unless File.respond_to?(:mkfifo) && IO.const_defined?(:NONBLOCK)
     require 'tmpdir'
     Dir.mktmpdir('rubytest-fifo') do |dir|
       fifo = "#{dir}/fifo"
@@ -45,7 +44,7 @@ class TestIOWaitUncommon < Test::Unit::TestCase
     rescue Errno::ENOENT
       return # Ignore silently
     rescue SystemCallError => e
-      skip "#{dev} could not be opened #{e.message} (#{e.class})"
+      omit "#{dev} could not be opened #{e.message} (#{e.class})"
     end
     if block
       yield fp
diff --git a/test/io/wait/test_ractor.rb b/test/io/wait/test_ractor.rb
index 3d286af77f..800216e610 100644
--- a/test/io/wait/test_ractor.rb
+++ b/test/io/wait/test_ractor.rb
@@ -1,13 +1,8 @@
 # frozen_string_literal: true
 require 'test/unit'
 require 'rbconfig'
-require 'io/wait'
 
 class TestIOWaitInRactor < Test::Unit::TestCase
-  def setup
-    omit unless defined? Ractor
-  end
-
   def test_ractor
     ext = "/io/wait.#{RbConfig::CONFIG['DLEXT']}"
     path = $".find {|path| path.end_with?(ext)}
@@ -19,4 +14,4 @@ class TestIOWaitInRactor < Test::Unit::TestCase
       puts r.take
     end;
   end
-end
+end if defined? Ractor