Running Aqua.jl on the code base: ambiguities

[matbesancon]

I ran Aqua.jl on the code base (current master) and found some ambiguities currently on master, posting that here to keep track of them, might PR later, otherwise somebody can pick it in the meantime:

julia> Aqua.test_ambiguities(JuMP)
7 ambiguities found
Ambiguity #1
add_to_expression!(aff::JuMP.GenericAffExpr{C,V}, new_coef::Union{Number, LinearAlgebra.UniformScaling}, new_var::V) where {C, V} in JuMP at /home/mbesancon/Documents/crptests/project_julia/JuMP.jl/src/aff_expr.jl:250
add_to_expression!(aff::JuMP.GenericAffExpr{C,V}, new_var::V, new_coef::Union{Number, LinearAlgebra.UniformScaling}) where {C, V} in JuMP at /home/mbesancon/Documents/crptests/project_julia/JuMP.jl/src/aff_expr.jl:256

Ambiguity #2
add_to_expression!(quad::JuMP.GenericQuadExpr{C,V}, new_var::Union{JuMP.GenericAffExpr{C,V}, V}, new_coef::Union{Number, LinearAlgebra.UniformScaling}) where {C, V} in JuMP at /home/mbesancon/Documents/crptests/project_julia/JuMP.jl/src/quad_expr.jl:184
add_to_expression!(quad::JuMP.GenericQuadExpr{C,V}, aff::JuMP.GenericAffExpr{C,V}, var::V) where {C, V} in JuMP at /home/mbesancon/Documents/crptests/project_julia/JuMP.jl/src/quad_expr.jl:227

Ambiguity #3
add_to_expression!(expr::Union{JuMP.GenericAffExpr{C,V}, JuMP.GenericQuadExpr{C,V}} where V where C, α::Union{Number, LinearAlgebra.UniformScaling}, β::Union{Number, LinearAlgebra.UniformScaling}) in JuMP at /home/mbesancon/Documents/crptests/project_julia/JuMP.jl/src/mutable_arithmetics.jl:176
add_to_expression!(quad::JuMP.GenericQuadExpr{C,V}, new_var::Union{JuMP.GenericAffExpr{C,V}, V}, new_coef::Union{Number, LinearAlgebra.UniformScaling}) where {C, V} in JuMP at /home/mbesancon/Documents/crptests/project_julia/JuMP.jl/src/quad_expr.jl:184

Ambiguity #4
add_to_expression!(quad::JuMP.GenericQuadExpr{C,V}, new_coef::Union{Number, LinearAlgebra.UniformScaling}, new_var::V) where {C, V} in JuMP at /home/mbesancon/Documents/crptests/project_julia/JuMP.jl/src/quad_expr.jl:177
add_to_expression!(quad::JuMP.GenericQuadExpr{C,V}, new_var::Union{JuMP.GenericAffExpr{C,V}, V}, new_coef::Union{Number, LinearAlgebra.UniformScaling}) where {C, V} in JuMP at /home/mbesancon/Documents/crptests/project_julia/JuMP.jl/src/quad_expr.jl:184

Ambiguity #5
add_to_expression!(aff::JuMP.GenericAffExpr{C,V}, new_var::V, new_coef::Union{Number, LinearAlgebra.UniformScaling}) where {C, V} in JuMP at /home/mbesancon/Documents/crptests/project_julia/JuMP.jl/src/aff_expr.jl:256
add_to_expression!(expr::Union{JuMP.GenericAffExpr{C,V}, JuMP.GenericQuadExpr{C,V}} where V where C, α::Union{Number, LinearAlgebra.UniformScaling}, β::Union{Number, LinearAlgebra.UniformScaling}) in JuMP at /home/mbesancon/Documents/crptests/project_julia/JuMP.jl/src/mutable_arithmetics.jl:176

Ambiguity #6
add_to_expression!(aff::JuMP.GenericAffExpr{C,V}, new_coef::Union{Number, LinearAlgebra.UniformScaling}, new_var::V) where {C, V} in JuMP at /home/mbesancon/Documents/crptests/project_julia/JuMP.jl/src/aff_expr.jl:250
add_to_expression!(expr::Union{JuMP.GenericAffExpr{C,V}, JuMP.GenericQuadExpr{C,V}} where V where C, α::Union{Number, LinearAlgebra.UniformScaling}, β::Union{Number, LinearAlgebra.UniformScaling}) in JuMP at /home/mbesancon/Documents/crptests/project_julia/JuMP.jl/src/mutable_arithmetics.jl:176

Ambiguity #7
add_to_expression!(expr::Union{JuMP.GenericAffExpr{C,V}, JuMP.GenericQuadExpr{C,V}} where V where C, α::Union{Number, LinearAlgebra.UniformScaling}, β::Union{Number, LinearAlgebra.UniformScaling}) in JuMP at /home/mbesancon/Documents/crptests/project_julia/JuMP.jl/src/mutable_arithmetics.jl:176
add_to_expression!(quad::JuMP.GenericQuadExpr{C,V}, new_coef::Union{Number, LinearAlgebra.UniformScaling}, new_var::V) where {C, V} in JuMP at /home/mbesancon/Documents/crptests/project_julia/JuMP.jl/src/quad_expr.jl:177

There are also failed tests with Aqua.test_unbound_args(JuMP) but I don't get exactly what this implies so leaving it for now

[odow]

Can you trigger these ambiguities?

[matbesancon]

good question, I should be able to check it this afternoon

[matbesancon]

So it's a bit contrived since it is assumed V will be a variable-like thing, but for the first one:

julia> aff = GenericAffExpr{Float64, Float64}()
julia> add_to_expression!(aff, 3.0, 2.0)
ERROR: MethodError: add_to_expression!(::GenericAffExpr{Float64,Float64}, ::Float64, ::Float64) is ambiguous. 

[matbesancon]

the second case:

add_to_expression!(quad::JuMP.GenericQuadExpr{C,V}, new_var::Union{JuMP.GenericAffExpr{C,V}, V}, new_coef::Union{Number, LinearAlgebra.UniformScaling}) where {C, V} in JuMP at /home/mbesancon/Documents/crptests/project_julia/JuMP.jl/src/quad_expr.jl:184
add_to_expression!(quad::JuMP.GenericQuadExpr{C,V}, aff::JuMP.GenericAffExpr{C,V}, var::V) where {C, V} in JuMP at /home/mbesancon/Documents/crptests/project_julia/JuMP.jl/src/quad_expr.jl:227

is roughly the same, ambiguity will be triggered when V <: _Constant

[matbesancon]

The last one seems more problematic and more prone to errors popping after the update of one library and not the other:

add_to_expression!(expr::Union{JuMP.GenericAffExpr{C,V}, JuMP.GenericQuadExpr{C,V}} where V where C, α::Union{Number, LinearAlgebra.UniformScaling}, β::Union{Number, LinearAlgebra.UniformScaling}) in JuMP at /home/mbesancon/Documents/crptests/project_julia/JuMP.jl/src/mutable_arithmetics.jl:176
add_to_expression!(quad::JuMP.GenericQuadExpr{C,V}, new_coef::Union{Number, LinearAlgebra.UniformScaling}, new_var::V) where {C, V} in JuMP at /home/mbesancon/Documents/crptests/project_julia/JuMP.jl/src/quad_expr.jl:177

[matbesancon]

I'll rerun these to see if it is still up

[matbesancon]

Running the latest version of Aqua on JuMP master:

julia> Aqua.test_ambiguities(JuMP)
7 ambiguities found
Ambiguity #1
add_to_expression!(aff::JuMP.GenericAffExpr{C,V}, new_coef::Union{Number, LinearAlgebra.UniformScaling}, new_var::V) where {C, V} in JuMP at /home/mbesancon/Documents/crptests/project_julia/JuMP.jl/src/aff_expr.jl:248
add_to_expression!(aff::JuMP.GenericAffExpr{C,V}, new_var::V, new_coef::Union{Number, LinearAlgebra.UniformScaling}) where {C, V} in JuMP at /home/mbesancon/Documents/crptests/project_julia/JuMP.jl/src/aff_expr.jl:254

Ambiguity #2
add_to_expression!(quad::JuMP.GenericQuadExpr{C,V}, new_coef::Union{Number, LinearAlgebra.UniformScaling}, new_var::V) where {C, V} in JuMP at /home/mbesancon/Documents/crptests/project_julia/JuMP.jl/src/quad_expr.jl:177
add_to_expression!(quad::JuMP.GenericQuadExpr{C,V}, new_var::Union{JuMP.GenericAffExpr{C,V}, V}, new_coef::Union{Number, LinearAlgebra.UniformScaling}) where {C, V} in JuMP at /home/mbesancon/Documents/crptests/project_julia/JuMP.jl/src/quad_expr.jl:184

Ambiguity #3
add_to_expression!(aff::JuMP.GenericAffExpr{C,V}, new_coef::Union{Number, LinearAlgebra.UniformScaling}, new_var::V) where {C, V} in JuMP at /home/mbesancon/Documents/crptests/project_julia/JuMP.jl/src/aff_expr.jl:248
add_to_expression!(expr::Union{JuMP.GenericAffExpr{C,V}, JuMP.GenericQuadExpr{C,V}} where V where C, α::Union{Number, LinearAlgebra.UniformScaling}, β::Union{Number, LinearAlgebra.UniformScaling}) in JuMP at /home/mbesancon/Documents/crptests/project_julia/JuMP.jl/src/mutable_arithmetics.jl:176

Ambiguity #4
add_to_expression!(expr::Union{JuMP.GenericAffExpr{C,V}, JuMP.GenericQuadExpr{C,V}} where V where C, α::Union{Number, LinearAlgebra.UniformScaling}, β::Union{Number, LinearAlgebra.UniformScaling}) in JuMP at /home/mbesancon/Documents/crptests/project_julia/JuMP.jl/src/mutable_arithmetics.jl:176
add_to_expression!(quad::JuMP.GenericQuadExpr{C,V}, new_coef::Union{Number, LinearAlgebra.UniformScaling}, new_var::V) where {C, V} in JuMP at /home/mbesancon/Documents/crptests/project_julia/JuMP.jl/src/quad_expr.jl:177

Ambiguity #5
add_to_expression!(expr::Union{JuMP.GenericAffExpr{C,V}, JuMP.GenericQuadExpr{C,V}} where V where C, α::Union{Number, LinearAlgebra.UniformScaling}, β::Union{Number, LinearAlgebra.UniformScaling}) in JuMP at /home/mbesancon/Documents/crptests/project_julia/JuMP.jl/src/mutable_arithmetics.jl:176
add_to_expression!(quad::JuMP.GenericQuadExpr{C,V}, new_var::Union{JuMP.GenericAffExpr{C,V}, V}, new_coef::Union{Number, LinearAlgebra.UniformScaling}) where {C, V} in JuMP at /home/mbesancon/Documents/crptests/project_julia/JuMP.jl/src/quad_expr.jl:184

Ambiguity #6
add_to_expression!(aff::JuMP.GenericAffExpr{C,V}, new_var::V, new_coef::Union{Number, LinearAlgebra.UniformScaling}) where {C, V} in JuMP at /home/mbesancon/Documents/crptests/project_julia/JuMP.jl/src/aff_expr.jl:254
add_to_expression!(expr::Union{JuMP.GenericAffExpr{C,V}, JuMP.GenericQuadExpr{C,V}} where V where C, α::Union{Number, LinearAlgebra.UniformScaling}, β::Union{Number, LinearAlgebra.UniformScaling}) in JuMP at /home/mbesancon/Documents/crptests/project_julia/JuMP.jl/src/mutable_arithmetics.jl:176

Ambiguity #7
add_to_expression!(quad::JuMP.GenericQuadExpr{C,V}, new_var::Union{JuMP.GenericAffExpr{C,V}, V}, new_coef::Union{Number, LinearAlgebra.UniformScaling}) where {C, V} in JuMP at /home/mbesancon/Documents/crptests/project_julia/JuMP.jl/src/quad_expr.jl:184
add_to_expression!(quad::JuMP.GenericQuadExpr{C,V}, aff::JuMP.GenericAffExpr{C,V}, var::V) where {C, V} in JuMP at /home/mbesancon/Documents/crptests/project_julia/JuMP.jl/src/quad_expr.jl:227

[matbesancon]

basically these problems arise from the face that we don't have an abstract type for V, the variable type parameter

[blegat]

In affine expression we actually allow VarType to be anything:

JuMP.jl/src/aff_expr.jl

Line 81 in eefafb1

mutable struct GenericAffExpr{CoefType,VarType} <: AbstractJuMPScalar

or the ambiguity to occur, one needs to use a number in VarType which would already be incorrect

[matbesancon]

in any case adding a type constraint on VarType would be unnecessarily breaking and this is the cause for all ambiguities, I'll close the issue