[ruby/json] Cleanup JSON.pretty_generate

https://github.com/ruby/json/commit/01c47a0555

ext/json/lib/json/common.rb

@@ -74,15 +74,6 @@ module JSON
       $VERBOSE = old
     end
 
-    def create_pretty_state
-      State.new(
-        :indent         => '  ',
-        :space          => ' ',
-        :object_nl      => "\n",
-        :array_nl       => "\n"
-      )
-    end
-
     # Returns the JSON generator module that is used by JSON.
     attr_reader :generator
 
@@ -366,6 +357,14 @@ module JSON
     generate(obj, opts)
   end
 
+  PRETTY_GENERATE_OPTIONS = {
+    indent: '  ',
+    space: ' ',
+    object_nl: "\n",
+    array_nl: "\n",
+  }.freeze
+  private_constant :PRETTY_GENERATE_OPTIONS
+
   # :call-seq:
   #   JSON.pretty_generate(obj, opts = nil) -> new_string
   #
@@ -397,22 +396,24 @@ module JSON
   #   }
   #
   def pretty_generate(obj, opts = nil)
-    if State === opts
-      state, opts = opts, nil
-    else
-      state = JSON.create_pretty_state
-    end
+    return state.generate(obj) if State === opts
+
+    options = PRETTY_GENERATE_OPTIONS
+
     if opts
-      if opts.respond_to? :to_hash
-        opts = opts.to_hash
-      elsif opts.respond_to? :to_h
-        opts = opts.to_h
-      else
-        raise TypeError, "can't convert #{opts.class} into Hash"
+      unless opts.is_a?(Hash)
+        if opts.respond_to? :to_hash
+          opts = opts.to_hash
+        elsif opts.respond_to? :to_h
+          opts = opts.to_h
+        else
+          raise TypeError, "can't convert #{opts.class} into Hash"
+        end
       end
-      state.configure(opts)
+      options = options.merge(opts)
     end
-    state.generate(obj)
+
+    State.generate(obj, options, nil)
   end
 
   # Sets or returns default options for the JSON.unsafe_load method.

test/json/json_generator_test.rb

@@ -199,26 +199,7 @@ class JSONGeneratorTest < Test::Unit::TestCase
     )
   end
 
-  def test_pretty_state
-    state = JSON.create_pretty_state
-    assert_equal({
-      :allow_nan             => false,
-      :array_nl              => "\n",
-      :as_json               => false,
-      :ascii_only            => false,
-      :buffer_initial_length => 1024,
-      :depth                 => 0,
-      :script_safe           => false,
-      :strict                => false,
-      :indent                => "  ",
-      :max_nesting           => 100,
-      :object_nl             => "\n",
-      :space                 => " ",
-      :space_before          => "",
-    }.sort_by { |n,| n.to_s }, state.to_h.sort_by { |n,| n.to_s })
-  end
-
-  def test_safe_state
+  def test_state_defaults
     state = JSON::State.new
     assert_equal({
       :allow_nan             => false,