use oneunit(T) in construct_seeds

Author: longemen3000

Project.toml

@@ -40,9 +40,10 @@ Calculus = "49dc2e85-a5d0-5ad3-a950-438e2897f1b9"
 DiffTests = "de460e47-3fe3-5279-bb4a-814414816d5d"
 InteractiveUtils = "b77e0a4c-d291-57a0-90e8-8db25a27a240"
 IrrationalConstants = "92d709cd-6900-40b7-9082-c6be49f344b6"
+Measurements = "eff96d63-e80a-5855-80a2-b1b0885c5ab7"
 SparseArrays = "2f01184e-e22b-5df5-ae63-d93ebab69eaf"
 StaticArrays = "90137ffa-7385-5640-81b9-e52037218182"
 Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
 
 [targets]
-test = ["Calculus", "DiffTests", "IrrationalConstants", "SparseArrays", "StaticArrays", "Test", "InteractiveUtils"]
+test = ["Calculus", "DiffTests", "IrrationalConstants", "Measurements", "SparseArrays", "StaticArrays", "Test", "InteractiveUtils"]

src/dual.jl

@@ -359,6 +359,9 @@ end
 @inline Base.one(d::Dual) = one(typeof(d))
 @inline Base.one(::Type{Dual{T,V,N}}) where {T,V,N} = Dual{T}(one(V), zero(Partials{N,V}))
 
+@inline Base.oneunit(d::Dual{T}) where {T} = Dual{T}(oneunit(value(d)), zero(partials(d)))
+@inline Base.oneunit(::Type{Dual{T,V,N}}) where {T,V,N} = Dual{T}(oneunit(V), zero(Partials{N,V}))
+
 @inline function Base.Int(d::Dual)
     all(iszero, partials(d)) || throw(InexactError(:Int, Int, d))
     Int(value(d))

src/partials.jl

@@ -7,7 +7,7 @@ end
 ##############################
 
 @generated function single_seed(::Type{Partials{N,V}}, ::Val{i}) where {N,V,i}
-    ex = Expr(:tuple, [ifelse(i === j, :(one(V)), :(zero(V))) for j in 1:N]...)
+    ex = Expr(:tuple, [ifelse(i === j, :(oneunit(V)), :(zero(V))) for j in 1:N]...)
     return :(Partials($(ex)))
 end
 

test/MiscTest.jl

@@ -9,6 +9,7 @@ using SparseArrays: sparse
 using StaticArrays
 using IrrationalConstants
 using LinearAlgebra
+using Measurements: Measurements
 
 include(joinpath(dirname(@__FILE__), "utils.jl"))
 
@@ -219,4 +220,8 @@ end
     @test B_mmatrix == B
 end
 
+#issue 651, using Measurements
+f651(x) = 2.1*x + 1
+@test ForwardDiff.derivative(f651,Measurements.measurement(1.0, 0.001)) == 2.1
+
 end # module