5 files changed, 64 insertions, 2 deletions
diff --git a/spec/ruby/core/kernel/eval_spec.rb b/spec/ruby/core/kernel/eval_spec.rb
index 454bc4a58e..5f4cd27da0 100644
--- a/spec/ruby/core/kernel/eval_spec.rb
+++ b/spec/ruby/core/kernel/eval_spec.rb
@@ -274,6 +274,26 @@ describe "Kernel#eval" do
     eval("").should == nil
   end
 
+  context "with shebang" do
+    it "ignores shebang with ruby interpreter" do
+      pid = eval(<<~CODE.b)
+        #!/usr/bin/env ruby
+        Process.pid
+      CODE
+
+      pid.should == Process.pid
+    end
+
+    it "ignores shebang with non-ruby interpreter" do
+      pid = eval(<<~CODE.b)
+        #!/usr/bin/env puma
+        Process.pid
+      CODE
+
+      pid.should == Process.pid
+    end
+  end
+
   # See language/magic_comment_spec.rb for more magic comments specs
   describe "with a magic encoding comment" do
     it "uses the magic comment encoding for the encoding of literal strings" do
diff --git a/spec/ruby/core/kernel/extend_spec.rb b/spec/ruby/core/kernel/extend_spec.rb
index 47b22f3a18..6342d8cae1 100644
--- a/spec/ruby/core/kernel/extend_spec.rb
+++ b/spec/ruby/core/kernel/extend_spec.rb
@@ -76,4 +76,16 @@ describe "Kernel#extend" do
       -> { @frozen.extend @module }.should raise_error(FrozenError)
     end
   end
+
+  it "updated class methods of a module when it extends self and includes another module" do
+    a = Module.new do
+      extend self
+    end
+    b = Module.new do
+      def foo; :foo; end
+    end
+
+    a.include b
+    a.foo.should == :foo
+  end
 end
diff --git a/spec/ruby/core/kernel/raise_spec.rb b/spec/ruby/core/kernel/raise_spec.rb
index 4f190c120b..a038dcf031 100644
--- a/spec/ruby/core/kernel/raise_spec.rb
+++ b/spec/ruby/core/kernel/raise_spec.rb
@@ -46,6 +46,22 @@ describe "Kernel#raise" do
     cause = StandardError.new
     -> { raise(cause: cause) }.should raise_error(ArgumentError)
   end
+
+  it "re-raises a rescued exception" do
+    -> do
+      begin
+        raise StandardError, "aaa"
+      rescue Exception
+        begin
+          raise ArgumentError
+        rescue ArgumentError
+        end
+
+        # should raise StandardError "aaa"
+        raise
+      end
+    end.should raise_error(StandardError, "aaa")
+  end
 end
 
 describe "Kernel#raise" do
diff --git a/spec/ruby/core/kernel/select_spec.rb b/spec/ruby/core/kernel/select_spec.rb
index e0d82f3079..df23414b28 100644
--- a/spec/ruby/core/kernel/select_spec.rb
+++ b/spec/ruby/core/kernel/select_spec.rb
@@ -10,9 +10,9 @@ end
 describe "Kernel.select" do
   it 'does not block when timeout is 0' do
     IO.pipe do |read, write|
-      IO.select([read], [], [], 0).should == nil
+      select([read], [], [], 0).should == nil
       write.write 'data'
-      IO.select([read], [], [], 0).should == [[read], [], []]
+      select([read], [], [], 0).should == [[read], [], []]
     end
   end
 end
diff --git a/spec/ruby/core/kernel/sleep_spec.rb b/spec/ruby/core/kernel/sleep_spec.rb
index d35e313006..1de52a707f 100644
--- a/spec/ruby/core/kernel/sleep_spec.rb
+++ b/spec/ruby/core/kernel/sleep_spec.rb
@@ -51,6 +51,20 @@ describe "Kernel#sleep" do
     t.value.should == 5
   end
 
+  platform_is_not :darwin do
+    it "sleeps with nanosecond precision" do
+      start_time = Process.clock_gettime(Process::CLOCK_MONOTONIC)
+      100.times do
+        sleep(0.0001)
+      end
+      end_time = Process.clock_gettime(Process::CLOCK_MONOTONIC)
+
+      actual_duration = end_time - start_time
+      (actual_duration > 0.01).should == true # 100 * 0.0001 => 0.01
+      (actual_duration < 0.03).should == true
+    end
+  end
+
   ruby_version_is ""..."3.3" do
     it "raises a TypeError when passed nil" do
       -> { sleep(nil)   }.should raise_error(TypeError)