3 files changed, 48 insertions, 32 deletions
diff --git a/spec/ruby/language/block_spec.rb b/spec/ruby/language/block_spec.rb
index 578d9cb3b0..cf0931b688 100644
--- a/spec/ruby/language/block_spec.rb
+++ b/spec/ruby/language/block_spec.rb
@@ -960,24 +960,27 @@ describe "Post-args" do
     end
 
     describe "with a circular argument reference" do
-      it "raises a SyntaxError if using an existing local with the same name as the argument" do
-        a = 1
-        -> {
-          @proc = eval "proc { |a=a| a }"
-        }.should raise_error(SyntaxError)
+      ruby_version_is ""..."3.4" do
+        it "raises a SyntaxError if using the argument in its default value" do
+          a = 1
+          -> {
+            eval "proc { |a=a| a }"
+          }.should raise_error(SyntaxError)
+        end
       end
 
-      it "raises a SyntaxError if there is an existing method with the same name as the argument" do
-        def a; 1; end
-        -> {
-          @proc = eval "proc { |a=a| a }"
-        }.should raise_error(SyntaxError)
+      ruby_version_is "3.4" do
+        it "is nil if using the argument in its default value" do
+          -> {
+            eval "proc { |a=a| a }.call"
+          }.call.should == nil
+        end
       end
+    end
 
-      it "calls an existing method with the same name as the argument if explicitly using ()" do
-        def a; 1; end
-        proc { |a=a()| a }.call.should == 1
-      end
+    it "calls an existing method with the same name as the argument if explicitly using ()" do
+      def a; 1; end
+      proc { |a=a()| a }.call.should == 1
     end
   end
 
diff --git a/spec/ruby/language/def_spec.rb b/spec/ruby/language/def_spec.rb
index 42e721c68c..ce8077eb69 100644
--- a/spec/ruby/language/def_spec.rb
+++ b/spec/ruby/language/def_spec.rb
@@ -197,15 +197,25 @@ describe "An instance method with a default argument" do
     foo(2,3,3).should == [2,3,[3]]
   end
 
-  it "raises a SyntaxError when there is an existing method with the same name as the local variable" do
-    def bar
-      1
+  ruby_version_is ""..."3.4" do
+    it "raises a SyntaxError if using the argument in its default value" do
+      -> {
+        eval "def foo(bar = bar)
+          bar
+        end"
+      }.should raise_error(SyntaxError)
+    end
+  end
+
+  ruby_version_is "3.4" do
+    it "is nil if using the argument in its default value" do
+      -> {
+        eval "def foo(bar = bar)
+          bar
+        end
+        foo"
+      }.call.should == nil
     end
-    -> {
-      eval "def foo(bar = bar)
-        bar
-      end"
-    }.should raise_error(SyntaxError)
   end
 
   it "calls a method with the same name as the local when explicitly using ()" do
diff --git a/spec/ruby/language/lambda_spec.rb b/spec/ruby/language/lambda_spec.rb
index 3ab3569ebe..ed5a1c69e8 100644
--- a/spec/ruby/language/lambda_spec.rb
+++ b/spec/ruby/language/lambda_spec.rb
@@ -263,18 +263,21 @@ describe "A lambda literal -> () { }" do
     end
 
     describe "with circular optional argument reference" do
-      it "raises a SyntaxError if using an existing local with the same name as the argument" do
-        a = 1
-        -> {
-          @proc = eval "-> (a=a) { a }"
-        }.should raise_error(SyntaxError)
+      ruby_version_is ""..."3.4" do
+        it "raises a SyntaxError if using the argument in its default value" do
+          a = 1
+          -> {
+            eval "-> (a=a) { a }"
+          }.should raise_error(SyntaxError)
+        end
       end
 
-      it "raises a SyntaxError if there is an existing method with the same name as the argument" do
-        def a; 1; end
-        -> {
-          @proc = eval "-> (a=a) { a }"
-        }.should raise_error(SyntaxError)
+      ruby_version_is "3.4" do
+        it "is nil if using the argument in its default value" do
+          -> {
+            eval "-> (a=a) { a }.call"
+          }.call.should == nil
+        end
       end
 
       it "calls an existing method with the same name as the argument if explicitly using ()" do