1 files changed, 4 insertions, 4 deletions
diff --git a/spec/ruby/core/string/dup_spec.rb b/spec/ruby/core/string/dup_spec.rb
index 73f71b8ffc..e367f7a311 100644
--- a/spec/ruby/core/string/dup_spec.rb
+++ b/spec/ruby/core/string/dup_spec.rb
@@ -21,7 +21,7 @@ describe "String#dup" do
   it "does not copy singleton methods" do
     def @obj.special() :the_one end
     dup = @obj.dup
-    -> { dup.special }.should raise_error(NameError)
+    -> { dup.special }.should.raise(NameError)
   end
 
   it "does not copy modules included in the singleton class" do
@@ -30,7 +30,7 @@ describe "String#dup" do
     end
 
     dup = @obj.dup
-    -> { dup.repr }.should raise_error(NameError)
+    -> { dup.repr }.should.raise(NameError)
   end
 
   it "does not copy constants defined in the singleton class" do
@@ -39,7 +39,7 @@ describe "String#dup" do
     end
 
     dup = @obj.dup
-    -> { class << dup; CLONE; end }.should raise_error(NameError)
+    -> { class << dup; CLONE; end }.should.raise(NameError)
   end
 
   it "does not modify the original string when changing dupped string" do
@@ -51,7 +51,7 @@ describe "String#dup" do
   end
 
   it "does not modify the original setbyte-mutated string when changing dupped string" do
-    orig = "a"
+    orig = +"a"
     orig.setbyte 0, "b".ord
     copy = orig.dup
     orig.setbyte 0, "c".ord