Add unit test for UnsupportedAttribute

[blegat]

See osqp/OSQP.jl#71 and oxfordcontrol/COSMO.jl#97

[odow]

Closed by #1419

MathOptInterface.jl/src/Test/test_model.jl

Lines 606 to 638 in 79c7927

	"""
	test_model_copy_to_UnsupportedAttribute(
	model::MOI.ModelLike,
	::Config,
	)
	Test `MOI.copy_to` when an attribute is unsupported.
	"""
	function test_model_copy_to_UnsupportedAttribute(model::MOI.ModelLike, ::Config)
	# ModelAttribute
	@test !MOI.supports(model, UnknownModelAttribute())
	@test_throws(
	MOI.UnsupportedAttribute,
	MOI.copy_to(model, BadModelAttributeModel()),
	)
	# VariableAttribute
	@test !MOI.supports(model, UnknownVariableAttribute(), MOI.VariableIndex)
	@test_throws(
	MOI.UnsupportedAttribute,
	MOI.copy_to(model, BadVariableAttributeModel()),
	)
	# ConstraintAttribute
	@test !MOI.supports(
	model,
	UnknownConstraintAttribute(),
	MOI.ConstraintIndex{MOI.SingleVariable,MOI.EqualTo{Float64}},
	)
	@test_throws(
	MOI.UnsupportedAttribute,
	MOI.copy_to(model, BadConstraintAttributeModel()),
	)
	return
	end

[blegat]

Nice, this should catch a few bugs in solvers