# Check if two fields values match
#
# ~~~
# var validator = new ObjectValidator
# validator.add new FieldsMatch("field1", "field2")
#
# assert validator.validate("""{ "field1": {}, "field2": {} }""")
# assert validator.validate("""{ "field1": "foo", "field2": "foo" }""")
# assert validator.validate("""{ "field1": null, "field2": null }""")
# assert validator.validate("""{}""")
#
# assert not validator.validate("""{ "field1": {}, "field2": [] }""")
# assert not validator.validate("""{ "field1": "foo", "field2": "bar" }""")
# assert not validator.validate("""{ "field1": null, "field2": "" }""")
# assert not validator.validate("""{ "field1": "foo" }""")
# ~~~
class FieldsMatch
	super FieldValidator

	# Other field to compare with
	var other: String

	redef fun validate_field(v, obj) do
		var val1 = obj.get_or_null(field)
		var val2 = obj.get_or_null(other)
		if val1 != val2 then
			v.validation.add_error(field, "Values mismatch: `{val1 or else "null"}` against `{val2 or else "null"}`")
			return false
		end
		return true
	end
end