1 files changed, 8 insertions, 4 deletions
diff --git a/spec/ruby/core/string/unpack/b_spec.rb b/spec/ruby/core/string/unpack/b_spec.rb
index 2cf5ebad34..23d93a8aea 100644
--- a/spec/ruby/core/string/unpack/b_spec.rb
+++ b/spec/ruby/core/string/unpack/b_spec.rb
@@ -88,7 +88,9 @@ describe "String#unpack with format 'B'" do
 
   ruby_version_is ""..."3.3" do
     it "ignores NULL bytes between directives" do
-      "\x80\x00".unpack("B\x00B").should == ["1", "0"]
+      suppress_warning do
+        "\x80\x00".unpack("B\x00B").should == ["1", "0"]
+      end
     end
   end
 
@@ -105,7 +107,7 @@ describe "String#unpack with format 'B'" do
   end
 
   it "decodes into US-ASCII string values" do
-    str = "s".force_encoding('UTF-8').unpack("B*")[0]
+    str = "s".dup.force_encoding('UTF-8').unpack("B*")[0]
     str.encoding.name.should == 'US-ASCII'
   end
 end
@@ -194,7 +196,9 @@ describe "String#unpack with format 'b'" do
 
   ruby_version_is ""..."3.3" do
     it "ignores NULL bytes between directives" do
-      "\x01\x00".unpack("b\x00b").should == ["1", "0"]
+      suppress_warning do
+        "\x01\x00".unpack("b\x00b").should == ["1", "0"]
+      end
     end
   end
 
@@ -211,7 +215,7 @@ describe "String#unpack with format 'b'" do
   end
 
   it "decodes into US-ASCII string values" do
-    str = "s".force_encoding('UTF-8').unpack("b*")[0]
+    str = "s".dup.force_encoding('UTF-8').unpack("b*")[0]
     str.encoding.name.should == 'US-ASCII'
   end
 end