JSON.dump inconsistent output for hash #563

require "minitest/autorun"
require "json"


class DumpTest < Minitest::Test
  def test_dump_duplicate_key_hash
    assert_equal "{\"a\":5,\"c\":{\"b\":6}}", JSON.dump({ 'a' => 1,  a: 5, c: { 'b' => 2, b: 6 } })
  end
end

Run options: --seed 18012

# Running:

F

Failure:
DumpTest#test_dump_duplicate_key_hash [nano-example.rb:7]:
--- expected
+++ actual
@@ -1 +1 @@
-"{\"a\":5,\"c\":{\"b\":6}}"
+"{\"a\":1,\"a\":5,\"c\":{\"b\":2,\"b\":6}}"



bin/rails test nano-example.rb:6



Finished in 0.007499s, 133.3511 runs/s, 133.3511 assertions/s.
1 runs, 1 assertions, 1 failures, 0 errors, 0 skips