Add version guards for Enumerator::ArithmeticSequence

* And keep specs for older versions.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@64411 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

spec/ruby/core/numeric/shared/step.rb

@@ -258,19 +258,24 @@ describe :numeric_step, :shared => true do
   end
 
   describe "when no block is given" do
-    it "returns an Enumerator when step is 0" do
-      1.send(@method, *@step_args.call(2, 0)).should be_an_instance_of(Enumerator::ArithmeticSequence)
+    step_enum_class = Enumerator
+    ruby_version_is "2.6" do
+      step_enum_class = Enumerator::ArithmeticSequence
     end
 
-    it "returns an Enumerator when not passed a block and self > stop" do
-      1.send(@method, *@step_args.call(0, 2)).should be_an_instance_of(Enumerator::ArithmeticSequence)
+    it "returns an #{step_enum_class} when step is 0" do
+      1.send(@method, *@step_args.call(2, 0)).should be_an_instance_of(step_enum_class)
     end
 
-    it "returns an Enumerator when not passed a block and self < stop" do
-      1.send(@method, *@step_args.call(2, 3)).should be_an_instance_of(Enumerator::ArithmeticSequence)
+    it "returns an #{step_enum_class} when not passed a block and self > stop" do
+      1.send(@method, *@step_args.call(0, 2)).should be_an_instance_of(step_enum_class)
     end
 
-    it "returns an Enumerator that uses the given step" do
+    it "returns an #{step_enum_class} when not passed a block and self < stop" do
+      1.send(@method, *@step_args.call(2, 3)).should be_an_instance_of(step_enum_class)
+    end
+
+    it "returns an #{step_enum_class} that uses the given step" do
       0.send(@method, *@step_args.call(5, 2)).to_a.should eql [0, 2, 4]
     end
 

spec/ruby/core/numeric/step_spec.rb

@@ -22,25 +22,44 @@ describe "Numeric#step" do
     it_behaves_like :numeric_step, :step
 
     describe "when no block is given" do
-      it "returns an Enumerator when step is 0" do
-        1.step(5, 0).should be_an_instance_of(Enumerator::ArithmeticSequence)
+      step_enum_class = Enumerator
+      ruby_version_is "2.6" do
+        step_enum_class = Enumerator::ArithmeticSequence
       end
 
-      it "returns an Enumerator when step is 0.0" do
-        1.step(2, 0.0).should be_an_instance_of(Enumerator::ArithmeticSequence)
+      it "returns an #{step_enum_class} when step is 0" do
+        1.step(5, 0).should be_an_instance_of(step_enum_class)
       end
 
-      describe "returned Enumerator" do
+      it "returns an #{step_enum_class} when step is 0.0" do
+        1.step(2, 0.0).should be_an_instance_of(step_enum_class)
+      end
+
+      describe "returned #{step_enum_class}" do
         describe "size" do
+          ruby_version_is ""..."2.6" do
             it "raises an ArgumentError when step is 0" do
               enum = 1.step(5, 0)
-            enum.size.should == Float::INFINITY
+              lambda { enum.size }.should raise_error(ArgumentError)
             end
 
             it "raises an ArgumentError when step is 0.0" do
               enum = 1.step(2, 0.0)
+              lambda { enum.size }.should raise_error(ArgumentError)
+            end
+          end
+
+          ruby_version_is "2.6" do
+            it "is infinity when step is 0" do
+              enum = 1.step(5, 0)
               enum.size.should == Float::INFINITY
             end
+
+            it "is infinity when step is 0.0" do
+              enum = 1.step(2, 0.0)
+              enum.size.should == Float::INFINITY
+            end
+          end
         end
       end
     end

spec/ruby/core/range/step_spec.rb

@@ -1,13 +1,18 @@
 require_relative '../../spec_helper'
 
 describe "Range#step" do
+  step_enum_class = Enumerator
+  ruby_version_is "2.6" do
+    step_enum_class = Enumerator::ArithmeticSequence
+  end
+
   before :each do
     ScratchPad.record []
   end
 
-  it "returns an arithmetic sequence when no block is given" do
+  it "returns an #{step_enum_class} when no block is given" do
     enum = (1..10).step(4)
-    enum.should be_an_instance_of(Enumerator::ArithmeticSequence)
+    enum.should be_an_instance_of(step_enum_class)
     enum.to_a.should eql([1, 5, 9])
   end
 
@@ -263,7 +268,7 @@ describe "Range#step" do
   end
 
   describe "when no block is given" do
-    describe "returned Enumerator::ArithmeticSequence" do
+    describe "returned #{step_enum_class}" do
       describe "size" do
         it "raises a TypeError if step does not respond to #to_int" do
           obj = mock("Range#step non-integer")
@@ -279,10 +284,29 @@ describe "Range#step" do
           lambda { enum.size }.should raise_error(TypeError)
         end
 
+        ruby_version_is ""..."2.6" do
+          it "raises an ArgumentError if step is 0" do
+            enum = (-1..1).step(0)
+            lambda { enum.size }.should raise_error(ArgumentError)
+          end
+
+          it "raises an ArgumentError if step is 0.0" do
+            enum = (-1..1).step(0.0)
+            lambda { enum.size }.should raise_error(ArgumentError)
+          end
+
+          it "raises an ArgumentError if step is negative" do
+            enum = (-1..1).step(-2)
+            lambda {  enum.size }.should raise_error(ArgumentError)
+          end
+        end
+
+        ruby_version_is "2.6" do
           it "returns Float::INFINITY for zero step" do
             (-1..1).step(0).size.should == Float::INFINITY
             (-1..1).step(0.0).size.should == Float::INFINITY
           end
+        end
 
         it "returns the ceil of range size divided by the number of steps" do
           (1..10).step(4).size.should == 3
@@ -297,10 +321,12 @@ describe "Range#step" do
           (-5...5).step(2).size.should == 5
         end
 
+        ruby_version_is "2.6" do
           it "returns the ceil of range size divided by the number of steps even if step is negative" do
             (-1..1).step(-1).size.should == 0
             (1..-1).step(-1).size.should == 3
           end
+        end
 
         it "returns the correct number of steps when one of the arguments is a float" do
           (-1..1.0).step(0.5).size.should == 5