Add GetAttributeNotAllowed error

[odow]

Closes #1777

With @blegat's example, the state is now EMPTY_OPTIMIZER, and the set is <= 2.0 as desired.

julia> using MathOptInterface

julia> const MOI = MathOptInterface
MathOptInterface

julia> MOI.Utilities.@model(
           NoFreeVariablesModel,
           (),
           (MOI.LessThan,),
           (MOI.Nonnegatives,),
           (),
           (),
           (MOI.ScalarAffineFunction,),
           (MOI.VectorOfVariables,),
           ()
       )
MathOptInterface.Utilities.GenericModel{T, MathOptInterface.Utilities.ObjectiveContainer{T}, MathOptInterface.Utilities.VariablesContainer{T}, NoFreeVariablesModelFunctionConstraints{T}} where T

julia> function MOI.supports_constraint(
           ::NoFreeVariablesModel{T},
           ::Type{MOI.VectorOfVariables},
           ::Type{MOI.Reals},
       ) where {T}
           return false
       end

julia> function MOI.supports_add_constrained_variables(
           ::NoFreeVariablesModel,
           ::Type{MOI.Nonnegatives},
       )
           return true
       end

julia> MOI.supports_add_constrained_variables(::NoFreeVariablesModel, ::Type{MOI.Reals}) = false

julia> function MOI.get(model::NoFreeVariablesModel, attr::MOI.ConstraintFunction, ci::MOI.ConstraintIndex)
           return MOI.get_fallback(model, attr, ci)
       end

julia> function bug()
           inner = NoFreeVariablesModel{Float64}()
           bridged = MOI.Bridges.full_bridge_optimizer(inner, Float64)
           model = MOI.Utilities.CachingOptimizer(
               MOI.Utilities.UniversalFallback(MOI.Utilities.Model{Float64}()),
               bridged,
           )
           x = MOI.add_variable(model)
           c = MOI.add_constraint(model, 1.0 * x, MOI.LessThan(1.0))
           MOI.Utilities.attach_optimizer(model)
           MOI.set(model, MOI.ConstraintSet(), c, MOI.LessThan(2.0))
           return model
           end
bug (generic function with 1 method)

julia> bug()
MOIU.CachingOptimizer{MOIB.LazyBridgeOptimizer{MOIU.GenericModel{Float64, MOIU.ObjectiveContainer{Float64}, MOIU.VariablesContainer{Float64}, NoFreeVariablesModelFunctionConstraints{Float64}}}, MOIU.UniversalFallback{MOIU.Model{Float64}}}
in state EMPTY_OPTIMIZER
in mode AUTOMATIC
with model cache MOIU.UniversalFallback{MOIU.Model{Float64}}
  fallback for MOIU.Model{Float64}
with optimizer MOIB.LazyBridgeOptimizer{MOIU.GenericModel{Float64, MOIU.ObjectiveContainer{Float64}, MOIU.VariablesContainer{Float64}, NoFreeVariablesModelFunctionConstraints{Float64}}}
  with 0 variable bridges
  with 0 constraint bridges
  with 0 objective bridges
  with inner model MOIU.GenericModel{Float64, MOIU.ObjectiveContainer{Float64}, MOIU.VariablesContainer{Float64}, NoFreeVariablesModelFunctionConstraints{Float64}}

julia> print(bug())
Feasibility

Subject to:

ScalarAffineFunction{Float64}-in-LessThan{Float64}
 0.0 + 1.0 v[1] <= 2.0

where previously

julia> bug()
ERROR: ArgumentError: MathOptInterface.Utilities.GenericModel{Float64, MathOptInterface.Utilities.ObjectiveContainer{Float64}, MathOptInterface.Utilities.VariablesContainer{Float64}, NoFreeVariablesModelFunctionConstraints{Float64}} does not support getting the attribute MathOptInterface.ConstraintFunction().
Stacktrace:
 [1] get_fallback(model::MathOptInterface.Utilities.GenericModel{Float64, MathOptInterface.Utilities.ObjectiveContainer{Float64}, MathOptInterface.Utilities.VariablesContainer{Float64}, NoFreeVariablesModelFunctionConstraints{Float64}}, attr::MathOptInterface.ConstraintFunction, #unused#::MathOptInterface.ConstraintIndex{MathOptInterface.ScalarAffineFunction{Float64}, MathOptInterface.LessThan{Float64}})
   @ MathOptInterface ~/.julia/packages/MathOptInterface/RuRWI/src/attributes.jl:367
 [2] get(model::MathOptInterface.Utilities.GenericModel{Float64, MathOptInterface.Utilities.ObjectiveContainer{Float64}, MathOptInterface.Utilities.VariablesContainer{Float64}, NoFreeVariablesModelFunctionConstraints{Float64}}, attr::MathOptInterface.ConstraintFunction, ci::MathOptInterface.ConstraintIndex{MathOptInterface.ScalarAffineFunction{Float64}, MathOptInterface.LessThan{Float64}})
   @ Main ./REPL[9]:2
 [3] get(b::MathOptInterface.Bridges.LazyBridgeOptimizer{MathOptInterface.Utilities.GenericModel{Float64, MathOptInterface.Utilities.ObjectiveContainer{Float64}, MathOptInterface.Utilities.VariablesContainer{Float64}, NoFreeVariablesModelFunctionConstraints{Float64}}}, attr::MathOptInterface.ConstraintFunction, ci::MathOptInterface.ConstraintIndex{MathOptInterface.ScalarAffineFunction{Float64}, MathOptInterface.LessThan{Float64}})
   @ MathOptInterface.Bridges ~/.julia/packages/MathOptInterface/RuRWI/src/Bridges/bridge_optimizer.jl:1222
 [4] set
   @ ~/.julia/packages/MathOptInterface/RuRWI/src/Bridges/bridge_optimizer.jl:1262 [inlined]
 [5] _replace_constraint_function_or_set(m::MathOptInterface.Utilities.CachingOptimizer{MathOptInterface.Bridges.LazyBridgeOptimizer{MathOptInterface.Utilities.GenericModel{Float64, MathOptInterface.Utilities.ObjectiveContainer{Float64}, MathOptInterface.Utilities.VariablesContainer{Float64}, NoFreeVariablesModelFunctionConstraints{Float64}}}, MathOptInterface.Utilities.UniversalFallback{MathOptInterface.Utilities.Model{Float64}}}, attr::MathOptInterface.ConstraintSet, cindex::MathOptInterface.ConstraintIndex{MathOptInterface.ScalarAffineFunction{Float64}, MathOptInterface.LessThan{Float64}}, replacement::MathOptInterface.LessThan{Float64})
   @ MathOptInterface.Utilities ~/.julia/packages/MathOptInterface/RuRWI/src/Utilities/cachingoptimizer.jl:595
 [6] set
   @ ~/.julia/packages/MathOptInterface/RuRWI/src/Utilities/cachingoptimizer.jl:627 [inlined]
 [7] bug()
   @ Main ./REPL[10]:11
 [8] top-level scope
   @ REPL[11]:1

[blegat]

Nice, thanks!