1 files changed, 8 insertions, 6 deletions
diff --git a/spec/ruby/core/array/pack/shared/unicode.rb b/spec/ruby/core/array/pack/shared/unicode.rb
index dd0f8b38aa..58ba8a8b23 100644
--- a/spec/ruby/core/array/pack/shared/unicode.rb
+++ b/spec/ruby/core/array/pack/shared/unicode.rb
@@ -26,7 +26,7 @@ describe :array_pack_unicode, shared: true do
   it "constructs strings with valid encodings" do
     str = [0x85].pack("U*")
     str.should == "\xc2\x85"
-    str.valid_encoding?.should be_true
+    str.valid_encoding?.should == true
   end
 
   it "encodes values larger than UTF-8 max codepoints" do
@@ -64,11 +64,13 @@ describe :array_pack_unicode, shared: true do
   it "raises a TypeError if #to_int does not return an Integer" do
     obj = mock('to_int')
     obj.should_receive(:to_int).and_return("5")
-    -> { [obj].pack("U") }.should raise_error(TypeError)
+    -> { [obj].pack("U") }.should.raise(TypeError)
   end
 
-  it "ignores NULL bytes between directives" do
-    [1, 2, 3].pack("U\x00U").should == "\x01\x02"
+  it "raise ArgumentError for NULL bytes between directives" do
+    -> {
+      [1, 2, 3].pack("U\x00U")
+    }.should.raise(ArgumentError, /unknown pack directive/)
   end
 
   it "ignores spaces between directives" do
@@ -76,11 +78,11 @@ describe :array_pack_unicode, shared: true do
   end
 
   it "raises a RangeError if passed a negative number" do
-    -> { [-1].pack("U") }.should raise_error(RangeError)
+    -> { [-1].pack("U") }.should.raise(RangeError)
   end
 
   it "raises a RangeError if passed a number larger than an unsigned 32-bit integer" do
-    -> { [2**32].pack("U") }.should raise_error(RangeError)
+    -> { [2**32].pack("U") }.should.raise(RangeError)
   end
 
   it "sets the output string to UTF-8 encoding" do