Fix promotion with nonconcrete types (#88)

* Fix promotion with nonconcrete types

* Add Combinatorics for tests

Author: blegat

Project.toml

@@ -19,3 +19,10 @@ MultivariatePolynomials = "0.3.5"
 MutableArithmetics = "0.2"
 Reexport = "0.2, 1.0"
 julia = "1"
+
+[extras]
+Combinatorics = "861a8166-3701-5b0c-9a16-15d98fcdc6aa"
+Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
+
+[targets]
+test = ["Combinatorics", "Test"]

src/DynamicPolynomials.jl

@@ -36,6 +36,7 @@ MP.polynomial(p::PolyType) = Polynomial(p)
 function MP.polynomial(p::PolyType{C}, ::Type{T}) where {C, T}
     return convert(Polynomial{C, T}, p)
 end
+MP.polynomialtype(::Type{Term{C}}) where {C} = Polynomial{C}
 MP.polynomialtype(::Type{Term{C, T}}) where {T, C} = Polynomial{C, T}
 MP.polynomialtype(::Type{T}, ::Type{<:DMonomialLike{C}}) where {T, C} = Polynomial{C, T}
 MP.polynomialtype(::Union{PolyType{C}, Type{<:PolyType{C}}}, ::Type{T}) where {C, T} = Polynomial{C, T}

src/promote.jl

@@ -1,3 +1,12 @@
 MP.promote_rule_constant(::Type{T}, ::Type{<:DMonomialLike{C}}) where {C, T} = Term{C, promote_type(T, Int)}
 MP.promote_rule_constant(::Type{S}, ::Type{Term{C, T}}) where {S, C, T} = Term{C, promote_type(S, T)}
 MP.promote_rule_constant(::Type{S}, ::Type{<:TermPoly{C, T}}) where {S, C, T} = Polynomial{C, promote_type(S, T)}
+MP.promote_rule_constant(::Type, ::Type{Term{C}}) where {C} = Any
+MP.promote_rule_constant(::Type, ::Type{Polynomial{C}}) where {C} = Any
+Base.promote_rule(::Type{Term{C}}, ::Type{Term{C, T}}) where {C, T} = Term{C}
+Base.promote_rule(::Type{Term{C, T}}, ::Type{Term{C}}) where {C, T} = Term{C}
+Base.promote_rule(::Type{Term{C}}, ::Type{<:DMonomialLike{C}}) where {C} = Term{C}
+Base.promote_rule(::Type{<:DMonomialLike{C}}, ::Type{Term{C}}) where {C} = Term{C}
+
+Base.convert(::Type{Term{C}}, m::DMonomialLike{C}) where {C} = convert(Term{C,Int}, m)
+Base.convert(::Type{Polynomial{C}}, t::Union{TermPoly{C},DMonomialLike{C}}) where {C} = MP.polynomial(t)