Add `Hash#transform_keys!` and `Hash#transform_values`.

mrbgems/mruby-hash-ext/mrblib/hash.rb

@@ -404,6 +404,26 @@ class Hash
   end
   ##
   # call-seq:
+  #    hsh.transform_keys! {|key| block } -> hsh
+  #    hsh.transform_keys!                -> an_enumerator
+  #
+  # Invokes the given block once for each key in <i>hsh</i>, replacing it
+  # with the new key returned by the block, and then returns <i>hsh</i>.
+  #
+  # If no block is given, an enumerator is returned instead.
+  #
+  def transform_keys!(&b)
+    return to_enum :transform_keys! unless block_given?
+    self.keys.each do |k|
+      value = self[k]
+      new_key = yield(k)
+      self.__delete(k)
+      self[new_key] = value
+    end
+    self
+  end
+  ##
+  # call-seq:
   #    hsh.transform_values {|value| block } -> new_hash
   #    hsh.transform_values                  -> an_enumerator
   #
@@ -421,4 +441,21 @@ class Hash
     end
     hash
   end
+  ##
+  # call-seq:
+  #    hsh.transform_values! {|key| block } -> hsh
+  #    hsh.transform_values!                -> an_enumerator
+  #
+  # Invokes the given block once for each value in the hash, replacing
+  # with the new value returned by the block, and then returns <i>hsh</i>.
+  #
+  # If no block is given, an enumerator is returned instead.
+  #
+  def transform_values!(&b)
+    return to_enum :transform_values! unless block_given?
+    self.keys.each do |k|
+      self[k] = yield(self[k])
+    end
+    self
+  end
 end

mrbgems/mruby-hash-ext/test/hash.rb

@@ -263,6 +263,8 @@ assert("Hash#transform_keys") do
                {1 => 100, 2 => 200})
   assert_equal(h.transform_keys.with_index{|k, i| "#{k}.#{i}"},
                {"1.0" => 100, "2.1" => 200})
+  assert_equal(h.transform_keys!{|k|k.to_i}, h)
+  assert_equal(h, {1 => 100, 2 => 200})
 end
 
 assert("Hash#transform_values") do
@@ -273,4 +275,6 @@ assert("Hash#transform_values") do
                {a: "1", b: "2", c: "3"})
   assert_equal(h.transform_values.with_index{|v, i| "#{v}.#{i}"},
                {a: "1.0", b: "2.1", c: "3.2"})
+  assert_equal(h.transform_values!{|v|v.to_s}, h)
+  assert_equal(h, {a: "1", b: "2", c: "3"})
 end