3 files changed, 89 insertions, 33 deletions
diff --git a/spec/ruby/core/kernel/proc_spec.rb b/spec/ruby/core/kernel/proc_spec.rb
index d9c09117e7..2c0e7988f9 100644
--- a/spec/ruby/core/kernel/proc_spec.rb
+++ b/spec/ruby/core/kernel/proc_spec.rb
@@ -36,14 +36,28 @@ describe "Kernel.proc" do
 end
 
 describe "Kernel#proc" do
-  it "uses the implicit block from an enclosing method" do
-    def some_method
-      proc
+  ruby_version_is ""..."2.7" do
+    it "uses the implicit block from an enclosing method" do
+      def some_method
+        proc
+      end
+
+      prc = some_method { "hello" }
+
+      prc.call.should == "hello"
     end
+  end
 
-    prc = some_method { "hello" }
+  ruby_version_is "2.7" do
+    it "can be created when called with no block" do
+      def some_method
+        proc
+      end
 
-    prc.call.should == "hello"
+      -> {
+        some_method { "hello" }
+      }.should complain(/tried to create Proc object without a block/)
+    end
   end
 
   it "needs to be reviewed for spec completeness"
diff --git a/spec/ruby/core/proc/block_pass_spec.rb b/spec/ruby/core/proc/block_pass_spec.rb
index 282f00b5a8..917a38efac 100644
--- a/spec/ruby/core/proc/block_pass_spec.rb
+++ b/spec/ruby/core/proc/block_pass_spec.rb
@@ -20,22 +20,39 @@ describe "Proc as a block pass argument" do
   end
 end
 
-describe "Proc as an implicit block pass argument" do
-  def revivify
-    Proc.new
-  end
+ruby_version_is ""..."2.7" do
+  describe "Proc as an implicit block pass argument" do
+    def revivify
+      Proc.new
+    end
 
-  it "remains the same object if re-vivified by the target method" do
-    p = Proc.new {}
-    p2 = revivify(&p)
-    p.should equal p2
-    p.should == p2
+    it "remains the same object if re-vivified by the target method" do
+      p = Proc.new {}
+      p2 = revivify(&p)
+      p.should equal p2
+      p.should == p2
+    end
+
+    it "remains the same object if reconstructed with Proc.new" do
+      p = Proc.new {}
+      p2 = Proc.new(&p)
+      p.should equal p2
+      p.should == p2
+    end
   end
+end
 
-  it "remains the same object if reconstructed with Proc.new" do
-    p = Proc.new {}
-    p2 = Proc.new(&p)
-    p.should equal p2
-    p.should == p2
+ruby_version_is "2.7" do
+  describe "Proc called with no block" do
+    def revivify
+      Proc.new
+    end
+
+    it "raises ArgumentError when called with no block" do
+      p = Proc.new {}
+      -> {
+        revivify(&p)
+      }.should
+    end
   end
 end
diff --git a/spec/ruby/core/proc/new_spec.rb b/spec/ruby/core/proc/new_spec.rb
index abdd187276..1c37c64478 100644
--- a/spec/ruby/core/proc/new_spec.rb
+++ b/spec/ruby/core/proc/new_spec.rb
@@ -95,16 +95,18 @@ describe "Proc.new with an associated block" do
     obj.second.should == 2
   end
 
-  it "returns a new Proc instance from the block passed to the containing method" do
-    prc = ProcSpecs.new_proc_in_method { "hello" }
-    prc.should be_an_instance_of(Proc)
-    prc.call.should == "hello"
-  end
+  ruby_version_is ""..."2.7" do
+    it "returns a new Proc instance from the block passed to the containing method" do
+      prc = ProcSpecs.new_proc_in_method { "hello" }
+      prc.should be_an_instance_of(Proc)
+      prc.call.should == "hello"
+    end
 
-  it "returns a new Proc instance from the block passed to the containing method" do
-    prc = ProcSpecs.new_proc_subclass_in_method { "hello" }
-    prc.should be_an_instance_of(ProcSpecs::ProcSubclass)
-    prc.call.should == "hello"
+    it "returns a new Proc instance from the block passed to the containing method" do
+      prc = ProcSpecs.new_proc_subclass_in_method { "hello" }
+      prc.should be_an_instance_of(ProcSpecs::ProcSubclass)
+      prc.call.should == "hello"
+    end
   end
 end
 
@@ -178,13 +180,36 @@ describe "Proc.new without a block" do
     lambda { ProcSpecs.new_proc_subclass_in_method }.should raise_error(ArgumentError)
   end
 
-  it "uses the implicit block from an enclosing method" do
-    def some_method
-      Proc.new
+  ruby_version_is ""..."2.7" do
+    it "uses the implicit block from an enclosing method" do
+      def some_method
+        Proc.new
+      end
+
+      prc = some_method { "hello" }
+
+      prc.call.should == "hello"
+    end
+  end
+
+  ruby_version_is "2.7" do
+    it "can be created if invoked from within a method with a block" do
+      lambda { ProcSpecs.new_proc_in_method { "hello" } }.should complain(/tried to create Proc object without a block/)
+    end
+
+    it "can be created if invoked on a subclass from within a method with a block" do
+      lambda { ProcSpecs.new_proc_subclass_in_method { "hello" } }.should complain(/tried to create Proc object without a block/)
     end
 
-    prc = some_method { "hello" }
 
-    prc.call.should == "hello"
+    it "can be create when called with no block" do
+      def some_method
+        Proc.new
+      end
+
+      -> {
+        some_method { "hello" }
+      }.should complain(/tried to create Proc object without a block/)
+    end
   end
 end