Ruby

def test_merge_mapping

input = <<-END

column-defaults:

- &id

name : id

type : int

pkey : true

tables:

- name : admin_users

columns:

- <<: *id

name: user_id

END

#

classmap = {

"tables" => Struct.new('Table', 'name', 'columns'),

"columns" => Struct.new('Column', 'name', 'type', 'pkey', 'required'),

}

#

visitor = Psych::Visitors::CustomClassVisitor.create(classmap)

tree = Psych.parse(input)

ydoc = visitor.accept(tree)

#

assert_kind_of classmap["tables"], ydoc['tables'][0]

assert_kind_of classmap["columns"], ydoc['tables'][0]['columns'][0]

#

table = ydoc['tables'][0]

assert_equal "int", table.columns[0].type # merged

assert_equal true, table.columns[0].pkey # merged

assert_equal "user_id", table.columns[0].name # ovrerwritten

end