14 files changed, 185 insertions, 289 deletions

diff --git a/spec/ruby/core/hash/shared/comparison.rb b/spec/ruby/core/hash/shared/comparison.rb
index 07564e4cec..2b62837232 100644
--- a/spec/ruby/core/hash/shared/comparison.rb
+++ b/spec/ruby/core/hash/shared/comparison.rb
@@ -1,15 +1,15 @@
 describe :hash_comparison, shared: true do
   it "raises a TypeError if the right operand is not a hash" do
-    -> { { a: 1 }.send(@method, 1) }.should raise_error(TypeError)
-    -> { { a: 1 }.send(@method, nil) }.should raise_error(TypeError)
-    -> { { a: 1 }.send(@method, []) }.should raise_error(TypeError)
+    -> { { a: 1 }.send(@method, 1) }.should.raise(TypeError)
+    -> { { a: 1 }.send(@method, nil) }.should.raise(TypeError)
+    -> { { a: 1 }.send(@method, []) }.should.raise(TypeError)
   end
 
   it "returns false if both hashes have the same keys but different values" do
     h1 = { a: 1 }
     h2 = { a: 2 }
 
-    h1.send(@method, h2).should be_false
-    h2.send(@method, h1).should be_false
+    h1.send(@method, h2).should == false
+    h2.send(@method, h1).should == false
   end
 end
diff --git a/spec/ruby/core/hash/shared/each.rb b/spec/ruby/core/hash/shared/each.rb
index b2483c8116..657c5d2c52 100644
--- a/spec/ruby/core/hash/shared/each.rb
+++ b/spec/ruby/core/hash/shared/each.rb
@@ -10,7 +10,7 @@ describe :hash_each, shared: true do
   it "yields the key and value of each pair to a block expecting |key, value|" do
     r = {}
     h = { a: 1, b: 2, c: 3, d: 5 }
-    h.send(@method) { |k,v| r[k.to_s] = v.to_s }.should equal(h)
+    h.send(@method) { |k,v| r[k.to_s] = v.to_s }.should.equal?(h)
     r.should == { "a" => "1", "b" => "2", "c" => "3", "d" => "5" }
   end
 
@@ -21,37 +21,18 @@ describe :hash_each, shared: true do
     ary.sort.should == ["a", "b", "c"]
   end
 
-  ruby_version_is ""..."3.0" do
-    it "yields 2 values and not an Array of 2 elements when given a callable of arity 2" do
-      obj = Object.new
-      def obj.foo(key, value)
-        ScratchPad << key << value
-      end
-
-      ScratchPad.record([])
-      { "a" => 1 }.send(@method, &obj.method(:foo))
-      ScratchPad.recorded.should == ["a", 1]
-
-      ScratchPad.record([])
-      { "a" => 1 }.send(@method, &-> key, value { ScratchPad << key << value })
-      ScratchPad.recorded.should == ["a", 1]
+  it "always yields an Array of 2 elements, even when given a callable of arity 2" do
+    obj = Object.new
+    def obj.foo(key, value)
     end
-  end
 
-  ruby_version_is "3.0" do
-    it "always yields an Array of 2 elements, even when given a callable of arity 2" do
-      obj = Object.new
-      def obj.foo(key, value)
-      end
-
-      -> {
-        { "a" => 1 }.send(@method, &obj.method(:foo))
-      }.should raise_error(ArgumentError)
+    -> {
+      { "a" => 1 }.send(@method, &obj.method(:foo))
+    }.should.raise(ArgumentError)
 
-      -> {
-        { "a" => 1 }.send(@method, &-> key, value { })
-      }.should raise_error(ArgumentError)
-    end
+    -> {
+      { "a" => 1 }.send(@method, &-> key, value { })
+    }.should.raise(ArgumentError)
   end
 
   it "yields an Array of 2 elements when given a callable of arity 1" do
@@ -72,7 +53,7 @@ describe :hash_each, shared: true do
 
     -> {
       { "a" => 1 }.send(@method, &obj.method(:foo))
-    }.should raise_error(ArgumentError)
+    }.should.raise(ArgumentError)
   end
 
   it "uses the same order as keys() and values()" do
diff --git a/spec/ruby/core/hash/shared/eql.rb b/spec/ruby/core/hash/shared/eql.rb
index 68db49f76d..512e1ad016 100644
--- a/spec/ruby/core/hash/shared/eql.rb
+++ b/spec/ruby/core/hash/shared/eql.rb
@@ -3,7 +3,7 @@ describe :hash_eql, shared: true do
     value = mock('x')
     value.should_not_receive(:==)
     value.should_not_receive(:eql?)
-    { 1 => value }.send(@method, { 2 => value }).should be_false
+    { 1 => value }.send(@method, { 2 => value }).should == false
   end
 
   it "returns false when the numbers of keys differ without comparing any elements" do
@@ -13,8 +13,8 @@ describe :hash_eql, shared: true do
     obj.should_not_receive(:==)
     obj.should_not_receive(:eql?)
 
-    {}.send(@method, h).should be_false
-    h.send(@method, {}).should be_false
+    {}.send(@method, h).should == false
+    h.send(@method, {}).should == false
   end
 
   it "first compares keys via hash" do
@@ -23,7 +23,7 @@ describe :hash_eql, shared: true do
     y = mock('y')
     y.should_receive(:hash).any_number_of_times.and_return(0)
 
-    { x => 1 }.send(@method, { y => 1 }).should be_false
+    { x => 1 }.send(@method, { y => 1 }).should == false
   end
 
   it "does not compare keys with different hash codes via eql?" do
@@ -35,39 +35,39 @@ describe :hash_eql, shared: true do
     x.should_receive(:hash).any_number_of_times.and_return(0)
     y.should_receive(:hash).any_number_of_times.and_return(1)
 
-    { x => 1 }.send(@method, { y => 1 }).should be_false
+    { x => 1 }.send(@method, { y => 1 }).should == false
   end
 
   it "computes equality for recursive hashes" do
     h = {}
     h[:a] = h
-    h.send(@method, h[:a]).should be_true
-    (h == h[:a]).should be_true
+    h.send(@method, h[:a]).should == true
+    (h == h[:a]).should == true
   end
 
   it "doesn't call to_hash on objects" do
     mock_hash = mock("fake hash")
     def mock_hash.to_hash() {} end
-    {}.send(@method, mock_hash).should be_false
+    {}.send(@method, mock_hash).should == false
   end
 
   it "computes equality for complex recursive hashes" do
     a, b = {}, {}
     a.merge! self: a, other: b
     b.merge! self: b, other: a
-    a.send(@method, b).should be_true # they both have the same structure!
+    a.send(@method, b).should == true # they both have the same structure!
 
     c = {}
     c.merge! other: c, self: c
-    c.send(@method, a).should be_true # subtle, but they both have the same structure!
+    c.send(@method, a).should == true # subtle, but they both have the same structure!
     a[:delta] = c[:delta] = a
-    c.send(@method, a).should be_false # not quite the same structure, as a[:other][:delta] = nil
+    c.send(@method, a).should == false # not quite the same structure, as a[:other][:delta] = nil
     c[:delta] = 42
-    c.send(@method, a).should be_false
+    c.send(@method, a).should == false
     a[:delta] = 42
-    c.send(@method, a).should be_false
+    c.send(@method, a).should == false
     b[:delta] = 42
-    c.send(@method, a).should be_true
+    c.send(@method, a).should == true
   end
 
   it "computes equality for recursive hashes & arrays" do
@@ -76,19 +76,19 @@ describe :hash_eql, shared: true do
     x << a
     y << c
     z << b
-    b.send(@method, c).should be_true # they clearly have the same structure!
-    y.send(@method, z).should be_true
-    a.send(@method, b).should be_true # subtle, but they both have the same structure!
-    x.send(@method, y).should be_true
+    b.send(@method, c).should == true # they clearly have the same structure!
+    y.send(@method, z).should == true
+    a.send(@method, b).should == true # subtle, but they both have the same structure!
+    x.send(@method, y).should == true
     y << x
-    y.send(@method, z).should be_false
+    y.send(@method, z).should == false
     z << x
-    y.send(@method, z).should be_true
+    y.send(@method, z).should == true
 
     a[:foo], a[:bar] = a[:bar], a[:foo]
-    a.send(@method, b).should be_false
+    a.send(@method, b).should == false
     b[:bar] = b[:foo]
-    b.send(@method, c).should be_false
+    b.send(@method, c).should == false
   end
 end
 
@@ -100,7 +100,7 @@ describe :hash_eql_additional, shared: true do
     def y.==(o) false end
     def x.eql?(o) false end
     def y.eql?(o) false end
-    { 1 => x }.send(@method, { 1 => y }).should be_false
+    { 1 => x }.send(@method, { 1 => y }).should == false
 
     x = mock('x')
     y = mock('y')
@@ -108,45 +108,45 @@ describe :hash_eql_additional, shared: true do
     def y.==(o) true end
     def x.eql?(o) true end
     def y.eql?(o) true end
-    { 1 => x }.send(@method, { 1 => y }).should be_true
+    { 1 => x }.send(@method, { 1 => y }).should == true
   end
 
   it "compares keys with eql? semantics" do
-    { 1.0 => "x" }.send(@method, { 1.0 => "x" }).should be_true
-    { 1.0 => "x" }.send(@method, { 1.0 => "x" }).should be_true
-    { 1 => "x" }.send(@method, { 1.0 => "x" }).should be_false
-    { 1.0 => "x" }.send(@method, { 1 => "x" }).should be_false
+    { 1.0 => "x" }.send(@method, { 1.0 => "x" }).should == true
+    { 1.0 => "x" }.send(@method, { 1.0 => "x" }).should == true
+    { 1 => "x" }.send(@method, { 1.0 => "x" }).should == false
+    { 1.0 => "x" }.send(@method, { 1 => "x" }).should == false
   end
 
   it "returns true if and only if other Hash has the same number of keys and each key-value pair matches" do
     a = { a: 5 }
     b = {}
-    a.send(@method, b).should be_false
+    a.send(@method, b).should == false
 
     b[:a] = 5
-    a.send(@method, b).should be_true
+    a.send(@method, b).should == true
 
     not_supported_on :opal do
       c = { "a" => 5 }
-      a.send(@method, c).should be_false
+      a.send(@method, c).should == false
     end
 
     c = { "A" => 5 }
-    a.send(@method, c).should be_false
+    a.send(@method, c).should == false
 
     c = { a: 6 }
-    a.send(@method, c).should be_false
+    a.send(@method, c).should == false
   end
 
   it "does not call to_hash on hash subclasses" do
-    { 5 => 6 }.send(@method, HashSpecs::ToHashHash[5 => 6]).should be_true
+    { 5 => 6 }.send(@method, HashSpecs::ToHashHash[5 => 6]).should == true
   end
 
   it "ignores hash class differences" do
     h = { 1 => 2, 3 => 4 }
-    HashSpecs::MyHash[h].send(@method, h).should be_true
-    HashSpecs::MyHash[h].send(@method, HashSpecs::MyHash[h]).should be_true
-    h.send(@method, HashSpecs::MyHash[h]).should be_true
+    HashSpecs::MyHash[h].send(@method, h).should == true
+    HashSpecs::MyHash[h].send(@method, HashSpecs::MyHash[h]).should == true
+    h.send(@method, HashSpecs::MyHash[h]).should == true
   end
 
   # Why isn't this true of eql? too ?
@@ -163,7 +163,7 @@ describe :hash_eql_additional, shared: true do
       obj
     end
 
-    { a[0] => 1 }.send(@method, { a[1] => 1 }).should be_false
+    { a[0] => 1 }.send(@method, { a[1] => 1 }).should == false
 
     a = Array.new(2) do
       obj = mock('0')
@@ -176,7 +176,7 @@ describe :hash_eql_additional, shared: true do
       obj
     end
 
-    { a[0] => 1 }.send(@method, { a[1] => 1 }).should be_true
+    { a[0] => 1 }.send(@method, { a[1] => 1 }).should == true
   end
 
   it "compares the values in self to values in other hash" do
@@ -185,20 +185,20 @@ describe :hash_eql_additional, shared: true do
 
     l_val.should_receive(:eql?).with(r_val).and_return(true)
 
-    { 1 => l_val }.eql?({ 1 => r_val }).should be_true
+    { 1 => l_val }.eql?({ 1 => r_val }).should == true
   end
 end
 
 describe :hash_eql_additional_more, shared: true do
   it "returns true if other Hash has the same number of keys and each key-value pair matches, even though the default-value are not same" do
-    Hash.new(5).send(@method, Hash.new(1)).should be_true
-    Hash.new {|h, k| 1}.send(@method, Hash.new {}).should be_true
-    Hash.new {|h, k| 1}.send(@method, Hash.new(2)).should be_true
+    Hash.new(5).send(@method, Hash.new(1)).should == true
+    Hash.new {|h, k| 1}.send(@method, Hash.new {}).should == true
+    Hash.new {|h, k| 1}.send(@method, Hash.new(2)).should == true
 
     d = Hash.new {|h, k| 1}
     e = Hash.new {}
     d[1] = 2
     e[1] = 2
-    d.send(@method, e).should be_true
+    d.send(@method, e).should == true
   end
 end
diff --git a/spec/ruby/core/hash/shared/equal.rb b/spec/ruby/core/hash/shared/equal.rb
deleted file mode 100644
index 43606437fe..0000000000
--- a/spec/ruby/core/hash/shared/equal.rb
+++ /dev/null
@@ -1,90 +0,0 @@
-describe :hash_equal, shared: true do
-  it "does not compare values when keys don't match" do
-    value = mock('x')
-    value.should_not_receive(:==)
-    value.should_not_receive(:eql?)
-    { 1 => value }.send(@method, { 2 => value }).should be_false
-  end
-
-  it "returns false when the numbers of keys differ without comparing any elements" do
-    obj = mock('x')
-    h = { obj => obj }
-
-    obj.should_not_receive(:==)
-    obj.should_not_receive(:eql?)
-
-    {}.send(@method, h).should be_false
-    h.send(@method, {}).should be_false
-  end
-
-  it "first compares keys via hash" do
-    x = mock('x')
-    x.should_receive(:hash).and_return(0)
-    y = mock('y')
-    y.should_receive(:hash).and_return(0)
-
-    { x => 1 }.send(@method, { y => 1 }).should be_false
-  end
-
-  it "does not compare keys with different hash codes via eql?" do
-    x = mock('x')
-    y = mock('y')
-    x.should_not_receive(:eql?)
-    y.should_not_receive(:eql?)
-
-    x.should_receive(:hash).and_return(0)
-    y.should_receive(:hash).and_return(1)
-
-    def x.hash() 0 end
-    def y.hash() 1 end
-
-    { x => 1 }.send(@method, { y => 1 }).should be_false
-  end
-
-  it "computes equality for recursive hashes" do
-    h = {}
-    h[:a] = h
-    h.send(@method, h[:a]).should be_true
-    (h == h[:a]).should be_true
-  end
-
-  it "computes equality for complex recursive hashes" do
-    a, b = {}, {}
-    a.merge! self: a, other: b
-    b.merge! self: b, other: a
-    a.send(@method, b).should be_true # they both have the same structure!
-
-    c = {}
-    c.merge! other: c, self: c
-    c.send(@method, a).should be_true # subtle, but they both have the same structure!
-    a[:delta] = c[:delta] = a
-    c.send(@method, a).should be_false # not quite the same structure, as a[:other][:delta] = nil
-    c[:delta] = 42
-    c.send(@method, a).should be_false
-    a[:delta] = 42
-    c.send(@method, a).should be_false
-    b[:delta] = 42
-    c.send(@method, a).should be_true
-  end
-
-  it "computes equality for recursive hashes & arrays" do
-    x, y, z = [], [], []
-    a, b, c = {foo: x, bar: 42}, {foo: y, bar: 42}, {foo: z, bar: 42}
-    x << a
-    y << c
-    z << b
-    b.send(@method, c).should be_true # they clearly have the same structure!
-    y.send(@method, z).should be_true
-    a.send(@method, b).should be_true # subtle, but they both have the same structure!
-    x.send(@method, y).should be_true
-    y << x
-    y.send(@method, z).should be_false
-    z << x
-    y.send(@method, z).should be_true
-
-    a[:foo], a[:bar] = a[:bar], a[:foo]
-    a.send(@method, b).should be_false
-    b[:bar] = b[:foo]
-    b.send(@method, c).should be_false
-  end
-end
diff --git a/spec/ruby/core/hash/shared/greater_than.rb b/spec/ruby/core/hash/shared/greater_than.rb
index 1f8b9fcfb7..dfe0b80250 100644
--- a/spec/ruby/core/hash/shared/greater_than.rb
+++ b/spec/ruby/core/hash/shared/greater_than.rb
@@ -5,11 +5,11 @@ describe :hash_greater_than, shared: true do
   end
 
   it "returns true if the other hash is a subset of self" do
-    @h1.send(@method, @h2).should be_true
+    @h1.send(@method, @h2).should == true
   end
 
   it "returns false if the other hash is not a subset of self" do
-    @h2.send(@method, @h1).should be_false
+    @h2.send(@method, @h1).should == false
   end
 
   it "converts the right operand to a hash before comparing" do
@@ -18,6 +18,6 @@ describe :hash_greater_than, shared: true do
       { a: 1, b: 2 }
     end
 
-    @h1.send(@method, o).should be_true
+    @h1.send(@method, o).should == true
   end
 end
diff --git a/spec/ruby/core/hash/shared/index.rb b/spec/ruby/core/hash/shared/index.rb
index 7f6a186464..dd4e89a9b4 100644
--- a/spec/ruby/core/hash/shared/index.rb
+++ b/spec/ruby/core/hash/shared/index.rb
@@ -10,13 +10,13 @@ describe :hash_index, shared: true do
 
   it "returns nil if the value is not found" do
     suppress_warning do # for Hash#index
-      { a: -1, b: 3.14, c: 2.718 }.send(@method, 1).should be_nil
+      { a: -1, b: 3.14, c: 2.718 }.send(@method, 1).should == nil
     end
   end
 
   it "doesn't return default value if the value is not found" do
     suppress_warning do # for Hash#index
-      Hash.new(5).send(@method, 5).should be_nil
+      Hash.new(5).send(@method, 5).should == nil
     end
   end
 
diff --git a/spec/ruby/core/hash/shared/iteration.rb b/spec/ruby/core/hash/shared/iteration.rb
index d27c2443f8..322e4b9a2f 100644
--- a/spec/ruby/core/hash/shared/iteration.rb
+++ b/spec/ruby/core/hash/shared/iteration.rb
@@ -5,15 +5,15 @@ describe :hash_iteration_no_block, shared: true do
   end
 
   it "returns an Enumerator if called on a non-empty hash without a block" do
-    @hsh.send(@method).should be_an_instance_of(Enumerator)
+    @hsh.send(@method).should.instance_of?(Enumerator)
   end
 
   it "returns an Enumerator if called on an empty hash without a block" do
-    @empty.send(@method).should be_an_instance_of(Enumerator)
+    @empty.send(@method).should.instance_of?(Enumerator)
   end
 
   it "returns an Enumerator if called on a frozen instance" do
     @hsh.freeze
-    @hsh.send(@method).should be_an_instance_of(Enumerator)
+    @hsh.send(@method).should.instance_of?(Enumerator)
   end
 end
diff --git a/spec/ruby/core/hash/shared/less_than.rb b/spec/ruby/core/hash/shared/less_than.rb
index cdc6f14546..071b3e97bb 100644
--- a/spec/ruby/core/hash/shared/less_than.rb
+++ b/spec/ruby/core/hash/shared/less_than.rb
@@ -5,11 +5,11 @@ describe :hash_less_than, shared: true do
   end
 
   it "returns true if self is a subset of the other hash" do
-    @h1.send(@method, @h2).should be_true
+    @h1.send(@method, @h2).should == true
   end
 
   it "returns false if self is not a subset of the other hash" do
-    @h2.send(@method, @h1).should be_false
+    @h2.send(@method, @h1).should == false
   end
 
   it "converts the right operand to a hash before comparing" do
@@ -18,6 +18,6 @@ describe :hash_less_than, shared: true do
       { a: 1, b: 2, c: 3 }
     end
 
-    @h1.send(@method, o).should be_true
+    @h1.send(@method, o).should == true
   end
 end
diff --git a/spec/ruby/core/hash/shared/replace.rb b/spec/ruby/core/hash/shared/replace.rb
deleted file mode 100644
index bea64384bb..0000000000
--- a/spec/ruby/core/hash/shared/replace.rb
+++ /dev/null
@@ -1,51 +0,0 @@
-describe :hash_replace, shared: true do
-  it "replaces the contents of self with other" do
-    h = { a: 1, b: 2 }
-    h.send(@method, c: -1, d: -2).should equal(h)
-    h.should == { c: -1, d: -2 }
-  end
-
-  it "tries to convert the passed argument to a hash using #to_hash" do
-    obj = mock('{1=>2,3=>4}')
-    obj.should_receive(:to_hash).and_return({ 1 => 2, 3 => 4 })
-
-    h = {}
-    h.send(@method, obj)
-    h.should == { 1 => 2, 3 => 4 }
-  end
-
-  it "calls to_hash on hash subclasses" do
-    h = {}
-    h.send(@method, HashSpecs::ToHashHash[1 => 2])
-    h.should == { 1 => 2 }
-  end
-
-  it "does not transfer default values" do
-    hash_a = {}
-    hash_b = Hash.new(5)
-    hash_a.send(@method, hash_b)
-    hash_a.default.should == 5
-
-    hash_a = {}
-    hash_b = Hash.new { |h, k| k * 2 }
-    hash_a.send(@method, hash_b)
-    hash_a.default(5).should == 10
-
-    hash_a = Hash.new { |h, k| k * 5 }
-    hash_b = Hash.new(-> { raise "Should not invoke lambda" })
-    hash_a.send(@method, hash_b)
-    hash_a.default.should == hash_b.default
-  end
-
-  it "raises a FrozenError if called on a frozen instance that would not be modified" do
-    -> do
-      HashSpecs.frozen_hash.send(@method, HashSpecs.frozen_hash)
-    end.should raise_error(FrozenError)
-  end
-
-  it "raises a FrozenError if called on a frozen instance that is modified" do
-    -> do
-      HashSpecs.frozen_hash.send(@method, HashSpecs.empty_frozen_hash)
-    end.should raise_error(FrozenError)
-  end
-end
diff --git a/spec/ruby/core/hash/shared/select.rb b/spec/ruby/core/hash/shared/select.rb
index 5170af50d6..b4f6d1b3ac 100644
--- a/spec/ruby/core/hash/shared/select.rb
+++ b/spec/ruby/core/hash/shared/select.rb
@@ -17,7 +17,7 @@ describe :hash_select, shared: true do
 
   it "returns a Hash of entries for which block is true" do
     a_pairs = { 'a' => 9, 'c' => 4, 'b' => 5, 'd' => 2 }.send(@method) { |k,v| v % 2 == 0 }
-    a_pairs.should be_an_instance_of(Hash)
+    a_pairs.should.instance_of?(Hash)
     a_pairs.sort.should == [['c', 4], ['d', 2]]
   end
 
@@ -33,11 +33,32 @@ describe :hash_select, shared: true do
   end
 
   it "returns an Enumerator when called on a non-empty hash without a block" do
-    @hsh.send(@method).should be_an_instance_of(Enumerator)
+    @hsh.send(@method).should.instance_of?(Enumerator)
   end
 
   it "returns an Enumerator when called on an empty hash without a block" do
-    @empty.send(@method).should be_an_instance_of(Enumerator)
+    @empty.send(@method).should.instance_of?(Enumerator)
+  end
+
+  it "does not retain the default value" do
+    h = Hash.new(1)
+    h.send(@method) { true }.default.should == nil
+    h[:a] = 1
+    h.send(@method) { true }.default.should == nil
+  end
+
+  it "does not retain the default_proc" do
+    pr = proc { |h, k| h[k] = [] }
+    h = Hash.new(&pr)
+    h.send(@method) { true }.default_proc.should == nil
+    h[:a] = 1
+    h.send(@method) { true }.default_proc.should == nil
+  end
+
+  it "retains compare_by_identity flag" do
+    h = { a: 9, c: 4 }.compare_by_identity
+    h2 = h.send(@method) { |k, _| k == :a }
+    h2.compare_by_identity?.should == true
   end
 
   it_should_behave_like :hash_iteration_no_block
@@ -56,7 +77,7 @@ describe :hash_select!, shared: true do
 
   it "is equivalent to keep_if if changes are made" do
     h = { a: 2 }
-    h.send(@method) { |k,v| v <= 1 }.should equal h
+    h.send(@method) { |k,v| v <= 1 }.should.equal? h
 
     h = { 1 => 2, 3 => 4 }
     all_args_select = []
@@ -66,7 +87,7 @@ describe :hash_select!, shared: true do
 
   it "removes all entries if the block is false" do
     h = { a: 1, b: 2, c: 3 }
-    h.send(@method) { |k,v| false }.should equal(h)
+    h.send(@method) { |k,v| false }.should.equal?(h)
     h.should == {}
   end
 
@@ -75,11 +96,11 @@ describe :hash_select!, shared: true do
   end
 
   it "raises a FrozenError if called on an empty frozen instance" do
-    -> { HashSpecs.empty_frozen_hash.send(@method) { false } }.should raise_error(FrozenError)
+    -> { HashSpecs.empty_frozen_hash.send(@method) { false } }.should.raise(FrozenError)
   end
 
   it "raises a FrozenError if called on a frozen instance that would not be modified" do
-    -> { HashSpecs.frozen_hash.send(@method) { true } }.should raise_error(FrozenError)
+    -> { HashSpecs.frozen_hash.send(@method) { true } }.should.raise(FrozenError)
   end
 
   it_should_behave_like :hash_iteration_no_block
diff --git a/spec/ruby/core/hash/shared/store.rb b/spec/ruby/core/hash/shared/store.rb
index b823ea45ca..05ef63face 100644
--- a/spec/ruby/core/hash/shared/store.rb
+++ b/spec/ruby/core/hash/shared/store.rb
@@ -9,7 +9,7 @@ describe :hash_store, shared: true do
 
   it "duplicates string keys using dup semantics" do
     # dup doesn't copy singleton methods
-    key = "foo"
+    key = +"foo"
     def key.reverse() "bar" end
     h = {}
     h.send(@method, key, 0)
@@ -44,7 +44,7 @@ describe :hash_store, shared: true do
   end
 
   it "duplicates and freezes string keys" do
-    key = "foo"
+    key = +"foo"
     h = {}
     h.send(@method, key, 0)
     key << "bar"
@@ -57,7 +57,7 @@ describe :hash_store, shared: true do
     key = "foo".freeze
     h = {}
     h.send(@method, key, 0)
-    h.keys[0].should equal(key)
+    h.keys[0].should.equal?(key)
   end
 
   it "keeps the existing key in the hash if there is a matching one" do
@@ -66,34 +66,34 @@ describe :hash_store, shared: true do
     key2 = HashSpecs::ByValueKey.new(13)
     h[key1] = 41
     key_in_hash = h.keys.last
-    key_in_hash.should equal(key1)
+    key_in_hash.should.equal?(key1)
     h[key2] = 42
     last_key = h.keys.last
-    last_key.should equal(key_in_hash)
-    last_key.should_not equal(key2)
+    last_key.should.equal?(key_in_hash)
+    last_key.should_not.equal?(key2)
   end
 
   it "keeps the existing String key in the hash if there is a matching one" do
     h = { "a" => 1, "b" => 2, "c" => 3, "d" => 4 }
-    key1 = "foo"
-    key2 = "foo"
-    key1.should_not equal(key2)
+    key1 = "foo".dup
+    key2 = "foo".dup
+    key1.should_not.equal?(key2)
     h[key1] = 41
     frozen_key = h.keys.last
-    frozen_key.should_not equal(key1)
+    frozen_key.should_not.equal?(key1)
     h[key2] = 42
-    h.keys.last.should equal(frozen_key)
-    h.keys.last.should_not equal(key2)
+    h.keys.last.should.equal?(frozen_key)
+    h.keys.last.should_not.equal?(key2)
   end
 
   it "raises a FrozenError if called on a frozen instance" do
-    -> { HashSpecs.frozen_hash.send(@method, 1, 2) }.should raise_error(FrozenError)
+    -> { HashSpecs.frozen_hash.send(@method, 1, 2) }.should.raise(FrozenError)
   end
 
   it "does not raise an exception if changing the value of an existing key during iteration" do
-      hash = {1 => 2, 3 => 4, 5 => 6}
-      hash.each { hash.send(@method, 1, :foo) }
-      hash.should == {1 => :foo, 3 => 4, 5 => 6}
+    hash = {1 => 2, 3 => 4, 5 => 6}
+    hash.each { hash.send(@method, 1, :foo) }
+    hash.should == {1 => :foo, 3 => 4, 5 => 6}
   end
 
   it "does not dispatch to hash for Boolean, Integer, Float, String, or Symbol" do
diff --git a/spec/ruby/core/hash/shared/to_s.rb b/spec/ruby/core/hash/shared/to_s.rb
index 2db3a96583..f88ca738a5 100644
--- a/spec/ruby/core/hash/shared/to_s.rb
+++ b/spec/ruby/core/hash/shared/to_s.rb
@@ -4,14 +4,8 @@ require_relative '../fixtures/classes'
 describe :hash_to_s, shared: true do
   it "returns a string representation with same order as each()" do
     h = { a: [1, 2], b: -2, d: -6, nil => nil }
-
-    pairs = []
-    h.each do |key, value|
-      pairs << key.inspect + '=>' + value.inspect
-    end
-
-    str = '{' + pairs.join(', ') + '}'
-    h.send(@method).should == str
+    expected = ruby_version_is("3.4") ? "{a: [1, 2], b: -2, d: -6, nil => nil}" : "{:a=>[1, 2], :b=>-2, :d=>-6, nil=>nil}"
+    h.send(@method).should == expected
   end
 
   it "calls #inspect on keys and values" do
@@ -19,31 +13,31 @@ describe :hash_to_s, shared: true do
     val = mock('val')
     key.should_receive(:inspect).and_return('key')
     val.should_receive(:inspect).and_return('val')
-
-    { key => val }.send(@method).should == '{key=>val}'
+    expected = ruby_version_is("3.4") ? "{key => val}" : "{key=>val}"
+    { key => val }.send(@method).should == expected
   end
 
   it "does not call #to_s on a String returned from #inspect" do
-    str = "abc"
+    str = +"abc"
     str.should_not_receive(:to_s)
-
-    { a: str }.send(@method).should == '{:a=>"abc"}'
+    expected = ruby_version_is("3.4") ? '{a: "abc"}' : '{:a=>"abc"}'
+    { a: str }.send(@method).should == expected
   end
 
   it "calls #to_s on the object returned from #inspect if the Object isn't a String" do
     obj = mock("Hash#inspect/to_s calls #to_s")
     obj.should_receive(:inspect).and_return(obj)
     obj.should_receive(:to_s).and_return("abc")
-
-    { a: obj }.send(@method).should == "{:a=>abc}"
+    expected = ruby_version_is("3.4") ? "{a: abc}" : "{:a=>abc}"
+    { a: obj }.send(@method).should == expected
   end
 
   it "does not call #to_str on the object returned from #inspect when it is not a String" do
     obj = mock("Hash#inspect/to_s does not call #to_str")
     obj.should_receive(:inspect).and_return(obj)
     obj.should_not_receive(:to_str)
-
-    { a: obj }.send(@method).should =~ /^\{:a=>#<MockObject:0x[0-9a-f]+>\}$/
+    expected_pattern = ruby_version_is("3.4") ? /^\{a: #<MockObject:0x[0-9a-f]+>\}$/ : /^\{:a=>#<MockObject:0x[0-9a-f]+>\}$/
+    { a: obj }.send(@method).should =~ expected_pattern
   end
 
   it "does not call #to_str on the object returned from #to_s when it is not a String" do
@@ -51,8 +45,8 @@ describe :hash_to_s, shared: true do
     obj.should_receive(:inspect).and_return(obj)
     obj.should_receive(:to_s).and_return(obj)
     obj.should_not_receive(:to_str)
-
-    { a: obj }.send(@method).should =~ /^\{:a=>#<MockObject:0x[0-9a-f]+>\}$/
+    expected_pattern = ruby_version_is("3.4") ? /^\{a: #<MockObject:0x[0-9a-f]+>\}$/ : /^\{:a=>#<MockObject:0x[0-9a-f]+>\}$/
+    { a: obj }.send(@method).should =~ expected_pattern
   end
 
   it "does not swallow exceptions raised by #to_s" do
@@ -60,30 +54,71 @@ describe :hash_to_s, shared: true do
     obj.should_receive(:inspect).and_return(obj)
     obj.should_receive(:to_s).and_raise(Exception)
 
-    -> { { a: obj }.send(@method) }.should raise_error(Exception)
+    -> { { a: obj }.send(@method) }.should.raise(Exception)
   end
 
   it "handles hashes with recursive values" do
     x = {}
     x[0] = x
-    x.send(@method).should == '{0=>{...}}'
+    expected = ruby_version_is("3.4") ? '{0 => {...}}' : '{0=>{...}}'
+    x.send(@method).should == expected
 
     x = {}
     y = {}
     x[0] = y
     y[1] = x
-    x.send(@method).should == "{0=>{1=>{...}}}"
-    y.send(@method).should == "{1=>{0=>{...}}}"
+    expected_x = ruby_version_is("3.4") ? '{0 => {1 => {...}}}' : '{0=>{1=>{...}}}'
+    expected_y = ruby_version_is("3.4") ? '{1 => {0 => {...}}}' : '{1=>{0=>{...}}}'
+    x.send(@method).should == expected_x
+    y.send(@method).should == expected_y
   end
 
   it "does not raise if inspected result is not default external encoding" do
     utf_16be = mock("utf_16be")
-    utf_16be.should_receive(:inspect).and_return(%<"utf_16be \u3042">.encode!(Encoding::UTF_16BE))
-
-    {a: utf_16be}.send(@method).should == '{:a=>"utf_16be \u3042"}'
+    utf_16be.should_receive(:inspect).and_return(%<"utf_16be \u3042">.encode(Encoding::UTF_16BE))
+    expected = ruby_version_is("3.4") ? '{a: "utf_16be \u3042"}' : '{:a=>"utf_16be \u3042"}'
+    {a: utf_16be}.send(@method).should == expected
   end
 
   it "works for keys and values whose #inspect return a frozen String" do
-    { true => false }.to_s.should == "{true=>false}"
+    expected = ruby_version_is("3.4") ? "{true => false}" : "{true=>false}"
+    { true => false }.to_s.should == expected
+  end
+
+  ruby_version_is "3.4" do
+    it "adds quotes to symbol keys that are not valid symbol literals" do
+      { "needs-quotes": 1 }.send(@method).should == '{"needs-quotes": 1}'
+    end
+
+    it "can be evaled" do
+      no_quote = '{a: 1, a!: 1, a?: 1}'
+      eval(no_quote).inspect.should == no_quote
+      [
+        '{"": 1}',
+        '{"0": 1, "!": 1, "%": 1, "&": 1, "*": 1, "+": 1, "-": 1, "/": 1, "<": 1, ">": 1, "^": 1, "`": 1, "|": 1, "~": 1}',
+        '{"@a": 1, "$a": 1, "+@": 1, "a=": 1, "[]": 1}',
+        '{"a\"b": 1, "@@a": 1, "<=>": 1, "===": 1, "[]=": 1}',
+      ].each do |quote|
+        eval(quote).inspect.should == quote
+      end
+    end
+
+    it "can be evaled when Encoding.default_external is changed" do
+      external = Encoding.default_external
+
+      Encoding.default_external = Encoding::ASCII
+      utf8_ascii_hash = '{"\\u3042": 1}'
+      eval(utf8_ascii_hash).inspect.should == utf8_ascii_hash
+
+      Encoding.default_external = Encoding::UTF_8
+      utf8_hash = "{\u3042: 1}"
+      eval(utf8_hash).inspect.should == utf8_hash
+
+      Encoding.default_external = Encoding::Windows_31J
+      sjis_hash = "{\x87]: 1}".dup.force_encoding('sjis')
+      eval(sjis_hash).inspect.should == sjis_hash
+    ensure
+      Encoding.default_external = external
+    end
   end
 end
diff --git a/spec/ruby/core/hash/shared/update.rb b/spec/ruby/core/hash/shared/update.rb
index 1b0eb809bf..6dbad1d6d0 100644
--- a/spec/ruby/core/hash/shared/update.rb
+++ b/spec/ruby/core/hash/shared/update.rb
@@ -1,14 +1,14 @@
 describe :hash_update, shared: true do
   it "adds the entries from other, overwriting duplicate keys. Returns self" do
     h = { _1: 'a', _2: '3' }
-    h.send(@method, _1: '9', _9: 2).should equal(h)
+    h.send(@method, _1: '9', _9: 2).should.equal?(h)
     h.should == { _1: "9", _2: "3", _9: 2 }
   end
 
   it "sets any duplicate key to the value of block if passed a block" do
     h1 = { a: 2, b: -1 }
     h2 = { a: -2, c: 1 }
-    h1.send(@method, h2) { |k,x,y| 3.14 }.should equal(h1)
+    h1.send(@method, h2) { |k,x,y| 3.14 }.should.equal?(h1)
     h1.should == { c: 1, b: -1, a: 3.14 }
 
     h1.send(@method, h1) { nil }
@@ -37,7 +37,7 @@ describe :hash_update, shared: true do
   it "raises a FrozenError on a frozen instance that is modified" do
     -> do
       HashSpecs.frozen_hash.send(@method, 1 => 2)
-    end.should raise_error(FrozenError)
+    end.should.raise(FrozenError)
   end
 
   it "checks frozen status before coercing an object with #to_hash" do
@@ -47,14 +47,14 @@ describe :hash_update, shared: true do
     def obj.to_hash() raise Exception, "should not receive #to_hash" end
     obj.freeze
 
-    -> { HashSpecs.frozen_hash.send(@method, obj) }.should raise_error(FrozenError)
+    -> { HashSpecs.frozen_hash.send(@method, obj) }.should.raise(FrozenError)
   end
 
   # see redmine #1571
   it "raises a FrozenError on a frozen instance that would not be modified" do
     -> do
       HashSpecs.frozen_hash.send(@method, HashSpecs.empty_frozen_hash)
-    end.should raise_error(FrozenError)
+    end.should.raise(FrozenError)
   end
 
   it "does not raise an exception if changing the value of an existing key during iteration" do
@@ -71,6 +71,6 @@ describe :hash_update, shared: true do
 
   it "accepts zero arguments" do
     hash = { a: 1 }
-    hash.send(@method).should eql(hash)
+    hash.send(@method).should.eql?(hash)
   end
 end
diff --git a/spec/ruby/core/hash/shared/values_at.rb b/spec/ruby/core/hash/shared/values_at.rb
index ef3b0e8ba0..4e4e60e7d6 100644
--- a/spec/ruby/core/hash/shared/values_at.rb
+++ b/spec/ruby/core/hash/shared/values_at.rb
@@ -1,9 +1,9 @@
 describe :hash_values_at, shared: true do
   it "returns an array of values for the given keys" do
     h = { a: 9, b: 'a', c: -10, d: nil }
-    h.send(@method).should be_kind_of(Array)
+    h.send(@method).should.is_a?(Array)
     h.send(@method).should == []
-    h.send(@method, :a, :d, :b).should be_kind_of(Array)
+    h.send(@method, :a, :d, :b).should.is_a?(Array)
     h.send(@method, :a, :d, :b).should == [9, nil, 'a']
   end
 end