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diff --git a/spec/ruby/core/array/equal_value_spec.rb b/spec/ruby/core/array/equal_value_spec.rb
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+++ b/spec/ruby/core/array/equal_value_spec.rb
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+require_relative '../../spec_helper'
+require_relative 'fixtures/classes'
+require_relative 'shared/eql'
+
+describe "Array#==" do
+  it_behaves_like :array_eql, :==
+
+  it "compares with an equivalent Array-like object using #to_ary" do
+    obj = mock('array-like')
+    obj.should_receive(:respond_to?).at_least(1).with(:to_ary).and_return(true)
+    obj.should_receive(:==).with([1]).at_least(1).and_return(true)
+
+    ([1] == obj).should be_true
+    ([[1]] == [obj]).should be_true
+    ([[[1], 3], 2] == [[obj, 3], 2]).should be_true
+
+    # recursive arrays
+    arr1 = [[1]]
+    arr1 << arr1
+    arr2 = [obj]
+    arr2 << arr2
+    (arr1 == arr2).should be_true
+    (arr2 == arr1).should be_true
+  end
+
+  it "returns false if any corresponding elements are not #==" do
+    a = ["a", "b", "c"]
+    b = ["a", "b", "not equal value"]
+    a.should_not == b
+
+    c = mock("c")
+    c.should_receive(:==).and_return(false)
+    ["a", "b", c].should_not == a
+  end
+
+  it "returns true if corresponding elements are #==" do
+    [].should == []
+    ["a", "c", 7].should == ["a", "c", 7]
+
+    [1, 2, 3].should == [1.0, 2.0, 3.0]
+
+    obj = mock('5')
+    obj.should_receive(:==).and_return(true)
+    [obj].should == [5]
+  end
+
+  # See https://bugs.ruby-lang.org/issues/1720
+  it "returns true for [NaN] == [NaN] because Array#== first checks with #equal? and NaN.equal?(NaN) is true" do
+    [Float::NAN].should == [Float::NAN]
+  end
+end