Merge pull request #28603 from mikeastock/alias-reverse-merge

Add an alias for reverse_merge to with_defaults

actionpack/lib/action_controller/metal/strong_parameters.rb

@@ -667,13 +667,15 @@ def reverse_merge(other_hash)
         other_hash.to_h.merge(@parameters)
       )
     end
+    alias_method :with_defaults, :reverse_merge
 
     # Returns current <tt>ActionController::Parameters</tt> instance with
     # current hash merged into +other_hash+.
     def reverse_merge!(other_hash)
       @parameters.merge!(other_hash.to_h) { |key, left, right| left }
       self
     end
+    alias_method :with_defaults!, :reverse_merge!
 
     # This is required by ActiveModel attribute assignment, so that user can
     # pass +Parameters+ to a mass assignment methods in a model. It should not

actionpack/test/controller/parameters/parameters_permit_test.rb

@@ -310,6 +310,14 @@ def walk_permitted(params)
     refute_predicate merged_params[:person], :empty?
   end
 
+  test "#with_defaults is an alias of reverse_merge" do
+    default_params = ActionController::Parameters.new(id: "1234", person: {}).permit!
+    merged_params = @params.with_defaults(default_params)
+
+    assert_equal "1234", merged_params[:id]
+    refute_predicate merged_params[:person], :empty?
+  end
+
   test "not permitted is sticky beyond reverse_merge" do
     refute_predicate @params.reverse_merge(a: "b"), :permitted?
   end
@@ -327,6 +335,14 @@ def walk_permitted(params)
     refute_predicate @params[:person], :empty?
   end
 
+  test "#with_defaults! is an alias of reverse_merge!" do
+    default_params = ActionController::Parameters.new(id: "1234", person: {}).permit!
+    @params.with_defaults!(default_params)
+
+    assert_equal "1234", @params[:id]
+    refute_predicate @params[:person], :empty?
+  end
+
   test "modifying the parameters" do
     @params[:person][:hometown] = "Chicago"
     @params[:person][:family] = { brother: "Jonas" }

activesupport/lib/active_support/core_ext/hash/reverse_merge.rb

@@ -12,11 +12,13 @@ class Hash
   def reverse_merge(other_hash)
     other_hash.merge(self)
   end
+  alias_method :with_defaults, :reverse_merge
 
   # Destructive +reverse_merge+.
   def reverse_merge!(other_hash)
     # right wins if there is no left
     merge!(other_hash) { |key, left, right| left }
   end
   alias_method :reverse_update, :reverse_merge!
+  alias_method :with_defaults!, :reverse_merge!
 end

activesupport/lib/active_support/hash_with_indifferent_access.rb

@@ -225,11 +225,13 @@ def merge(hash, &block)
     def reverse_merge(other_hash)
       super(self.class.new(other_hash))
     end
+    alias_method :with_defaults, :reverse_merge
 
     # Same semantics as +reverse_merge+ but modifies the receiver in-place.
     def reverse_merge!(other_hash)
       replace(reverse_merge(other_hash))
     end
+    alias_method :with_defaults!, :reverse_merge!
 
     # Replaces the contents of this hash with other_hash.
     #

activesupport/test/core_ext/hash_ext_test.rb

@@ -535,6 +535,16 @@ def test_indifferent_reverse_merging
     assert_equal "clobber", hash[:another]
   end
 
+  def test_indifferent_with_defaults_aliases_reverse_merge
+    hash = HashWithIndifferentAccess.new key: :old_value
+    actual = hash.with_defaults key: :new_value
+    assert_equal :old_value, actual[:key]
+
+    hash = HashWithIndifferentAccess.new key: :old_value
+    hash.with_defaults! key: :new_value
+    assert_equal :old_value, hash[:key]
+  end
+
   def test_indifferent_deleting
     get_hash = proc { { a: "foo" }.with_indifferent_access }
     hash = get_hash.call
@@ -848,6 +858,21 @@ def test_reverse_merge
     assert_equal expected, merged
   end
 
+  def test_with_defaults_aliases_reverse_merge
+    defaults = { a: "x", b: "y", c: 10 }.freeze
+    options  = { a: 1, b: 2 }
+    expected = { a: 1, b: 2, c: 10 }
+
+    # Should be an alias for reverse_merge
+    assert_equal expected, options.with_defaults(defaults)
+    assert_not_equal expected, options
+
+    # Should be an alias for reverse_merge!
+    merged = options.dup
+    assert_equal expected, merged.with_defaults!(defaults)
+    assert_equal expected, merged
+  end
+
   def test_slice
     original = { a: "x", b: "y", c: 10 }
     expected = { a: "x", b: "y" }