avoid defining one arg hash (#631)

these are not really meant to be extended

Author: KristofferC

src/dual.jl

@@ -336,7 +336,6 @@ Base.exponent(x::Dual) = exponent(value(x))
 
 Base.div(x::Dual, y::Dual, r::RoundingMode) = div(value(x), value(y), r)
 
-Base.hash(d::Dual) = hash(value(d))
 Base.hash(d::Dual, hsh::UInt) = hash(value(d), hsh)
 
 function Base.read(io::IO, ::Type{Dual{T,V,N}}) where {T,V,N}

src/partials.jl

@@ -52,8 +52,7 @@ Base.:(==)(a::Partials{N}, b::Partials{N}) where {N} = a.values == b.values
 
 const PARTIALS_HASH = hash(Partials)
 
-Base.hash(partials::Partials) = hash(partials.values, PARTIALS_HASH)
-Base.hash(partials::Partials, hsh::UInt64) = hash(hash(partials), hsh)
+Base.hash(partials::Partials, hsh::UInt64) = hash(hash(partials.values, PARTIALS_HASH), hsh)
 
 @inline Base.copy(partials::Partials) = partials
 

test/PartialsTest.jl

@@ -62,7 +62,6 @@ samerng() = MersenneTwister(1)
     @test isequal(PARTIALS, copy(PARTIALS))
     @test isequal(PARTIALS, PARTIALS2) == (N == 0)
 
-    @test hash(PARTIALS) == hash(VALUES, ForwardDiff.PARTIALS_HASH)
     @test hash(PARTIALS) == hash(copy(PARTIALS))
     @test hash(PARTIALS, hash(1)) == hash(copy(PARTIALS), hash(1))
     @test hash(PARTIALS, hash(1)) == hash(copy(PARTIALS), hash(1))