methods on array subclass return array instance

core/array/drop_spec.rb

@@ -1,4 +1,5 @@
 require_relative '../../spec_helper'
+require_relative 'fixtures/classes'
 
 describe "Array#drop" do
   it "removes the specified number of elements from the start of the array" do
@@ -48,4 +49,16 @@
 
     -> { [1, 2].drop(obj) }.should raise_error(TypeError)
   end
+
+  ruby_version_is ''...'3.0' do
+    it 'returns a subclass instance for Array subclasses' do
+      ArraySpecs::MyArray[1, 2, 3, 4, 5].drop(1).should be_an_instance_of(ArraySpecs::MyArray)
+    end
+  end
+
+  ruby_version_is '3.0' do
+    it 'returns a Array instance for Array subclasses' do
+      ArraySpecs::MyArray[1, 2, 3, 4, 5].drop(1).should be_an_instance_of(Array)
+    end
+  end
 end

core/array/drop_while_spec.rb

@@ -1,4 +1,5 @@
 require_relative '../../spec_helper'
+require_relative 'fixtures/classes'
 
 describe "Array#drop_while" do
   it "removes elements from the start of the array while the block evaluates to true" do
@@ -12,4 +13,16 @@
   it "removes elements from the start of the array until the block returns false" do
     [1, 2, 3, false, 5].drop_while { |n| n }.should == [false, 5]
   end
+
+  ruby_version_is ''...'3.0' do
+    it 'returns a subclass instance for Array subclasses' do
+      ArraySpecs::MyArray[1, 2, 3, 4, 5].drop_while { |n| n < 4 }.should be_an_instance_of(ArraySpecs::MyArray)
+    end
+  end
+
+  ruby_version_is '3.0' do
+    it 'returns a Array instance for Array subclasses' do
+      ArraySpecs::MyArray[1, 2, 3, 4, 5].drop_while { |n| n < 4 }.should be_an_instance_of(Array)
+    end
+  end
 end

core/array/slice_spec.rb

@@ -185,6 +185,64 @@ def to.to_int() -2 end
       a.should == [3, 4]
     end
   end
+
+  describe "with a subclass of Array" do
+    before :each do
+      @array = ArraySpecs::MyArray[1, 2, 3, 4, 5]
+    end
+
+    ruby_version_is ''...'3.0' do
+      it "returns a subclass instance with [n, m]" do
+        @array.slice!(0, 2).should be_an_instance_of(ArraySpecs::MyArray)
+      end
+
+      it "returns a subclass instance with [-n, m]" do
+        @array.slice!(-3, 2).should be_an_instance_of(ArraySpecs::MyArray)
+      end
+
+      it "returns a subclass instance with [n..m]" do
+        @array.slice!(1..3).should be_an_instance_of(ArraySpecs::MyArray)
+      end
+
+      it "returns a subclass instance with [n...m]" do
+        @array.slice!(1...3).should be_an_instance_of(ArraySpecs::MyArray)
+      end
+
+      it "returns a subclass instance with [-n..-m]" do
+        @array.slice!(-3..-1).should be_an_instance_of(ArraySpecs::MyArray)
+      end
+
+      it "returns a subclass instance with [-n...-m]" do
+        @array.slice!(-3...-1).should be_an_instance_of(ArraySpecs::MyArray)
+      end
+    end
+
+    ruby_version_is '3.0' do
+      it "returns a Array instance with [n, m]" do
+        @array.slice!(0, 2).should be_an_instance_of(Array)
+      end
+
+      it "returns a Array instance with [-n, m]" do
+        @array.slice!(-3, 2).should be_an_instance_of(Array)
+      end
+
+      it "returns a Array instance with [n..m]" do
+        @array.slice!(1..3).should be_an_instance_of(Array)
+      end
+
+      it "returns a Array instance with [n...m]" do
+        @array.slice!(1...3).should be_an_instance_of(Array)
+      end
+
+      it "returns a Array instance with [-n..-m]" do
+        @array.slice!(-3..-1).should be_an_instance_of(Array)
+      end
+
+      it "returns a Array instance with [-n...-m]" do
+        @array.slice!(-3...-1).should be_an_instance_of(Array)
+      end
+    end
+  end
 end
 
 describe "Array#slice" do

core/array/take_spec.rb

@@ -1,4 +1,5 @@
 require_relative '../../spec_helper'
+require_relative 'fixtures/classes'
 
 describe "Array#take" do
   it "returns the first specified number of elements" do
@@ -24,4 +25,16 @@
   it "raises an ArgumentError when the argument is negative" do
     ->{ [1].take(-3) }.should raise_error(ArgumentError)
   end
+
+  ruby_version_is ''...'3.0' do
+    it 'returns a subclass instance for Array subclasses' do
+      ArraySpecs::MyArray[1, 2, 3, 4, 5].take(1).should be_an_instance_of(ArraySpecs::MyArray)
+    end
+  end
+
+  ruby_version_is '3.0' do
+    it 'returns a Array instance for Array subclasses' do
+      ArraySpecs::MyArray[1, 2, 3, 4, 5].take(1).should be_an_instance_of(Array)
+    end
+  end
 end

core/array/take_while_spec.rb

@@ -1,4 +1,5 @@
 require_relative '../../spec_helper'
+require_relative 'fixtures/classes'
 
 describe "Array#take_while" do
   it "returns all elements until the block returns false" do
@@ -12,4 +13,16 @@
   it "returns all elements until the block returns false" do
     [1, 2, false, 4].take_while{ |element| element }.should == [1, 2]
   end
+
+  ruby_version_is ''...'3.0' do
+    it 'returns a subclass instance for Array subclasses' do
+      ArraySpecs::MyArray[1, 2, 3, 4, 5].take_while { |n| n < 4 }.should be_an_instance_of(ArraySpecs::MyArray)
+    end
+  end
+
+  ruby_version_is '3.0' do
+    it 'returns a Array instance for Array subclasses' do
+      ArraySpecs::MyArray[1, 2, 3, 4, 5].take_while { |n| n < 4 }.should be_an_instance_of(Array)
+    end
+  end
 end