Introduce JSON::Coder

Co-authored-by: Jean Boussier <jean.boussier@gmail.com>

test/json/json_coder_test.rb

@@ -0,0 +1,38 @@
+#!/usr/bin/env ruby
+# frozen_string_literal: true
+
+require_relative 'test_helper'
+
+class JSONCoderTest < Test::Unit::TestCase
+  def test_json_coder_with_proc
+    coder = JSON::Coder.new do |object|
+      "[Object object]"
+    end
+    assert_equal %(["[Object object]"]), coder.dump([Object.new])
+  end
+
+  def test_json_coder_with_proc_with_unsupported_value
+    coder = JSON::Coder.new do |object|
+      Object.new
+    end
+    assert_raise(JSON::GeneratorError) { coder.dump([Object.new]) }
+  end
+
+  def test_json_coder_options
+    coder = JSON::Coder.new(array_nl: "\n") do |object|
+      42
+    end
+
+    assert_equal "[\n42\n]", coder.dump([Object.new])
+  end
+
+  def test_json_coder_load
+    coder = JSON::Coder.new
+    assert_equal [1,2,3], coder.load("[1,2,3]")
+  end
+
+  def test_json_coder_load_options
+    coder = JSON::Coder.new(symbolize_names: true)
+    assert_equal({a: 1}, coder.load('{"a":1}'))
+  end
+end