fix partial missing bug (#191)

This PR fixes TuringLang/Turing.jl#1464.

Co-authored-by: David Widmann <[email protected]>

Author: mohamed82008

Project.toml

@@ -1,6 +1,6 @@
 name = "DynamicPPL"
 uuid = "366bfd00-2699-11ea-058f-f148b4cae6d8"
-version = "0.10.1"
+version = "0.10.2"
 
 [deps]
 AbstractMCMC = "80f14c24-f653-4e6a-9b94-39d6b0f70001"

src/compiler.jl

@@ -369,16 +369,47 @@ Convert the `value` to the correct type for the `sampler` and the `vi` object.
 function matchingvalue(sampler, vi, value)
     T = typeof(value)
     if hasmissing(T)
-        return convert(get_matching_type(sampler, vi, T), value)
+        _value = convert(get_matching_type(sampler, vi, T), value)
+        if _value === value
+            return deepcopy(_value)
+        else
+            return _value
+        end
     else
         return value
     end
 end
 matchingvalue(sampler, vi, value::FloatOrArrayType) = get_matching_type(sampler, vi, value)
 
 """
-    get_matching_type(spl, vi, ::Type{T}) where {T}
-Get the specialized version of type `T` for sampler `spl`. For example,
-if `T === Float64` and `spl::Hamiltonian`, the matching type is `eltype(vi[spl])`.
+    get_matching_type(spl::AbstractSampler, vi, ::Type{T}) where {T}
+
+Get the specialized version of type `T` for sampler `spl`.
+
+For example, if `T === Float64` and `spl::Hamiltonian`, the matching type is
+`eltype(vi[spl])`.
 """
-function get_matching_type end
+get_matching_type(spl::AbstractSampler, vi, ::Type{T}) where {T} = T
+function get_matching_type(
+    spl::AbstractSampler, 
+    vi, 
+    ::Type{<:Union{Missing, AbstractFloat}},
+)
+    return Union{Missing, floatof(eltype(vi, spl))}
+end
+function get_matching_type(
+    spl::AbstractSampler,
+    vi,
+    ::Type{<:AbstractFloat},
+)
+    return floatof(eltype(vi, spl))
+end
+function get_matching_type(spl::AbstractSampler, vi, ::Type{<:Array{T,N}}) where {T,N}
+    return Array{get_matching_type(spl, vi, T), N}
+end
+function get_matching_type(spl::AbstractSampler, vi, ::Type{<:Array{T}}) where T
+    return Array{get_matching_type(spl, vi, T)}
+end
+
+floatof(::Type{T}) where {T <: Real} = typeof(one(T)/one(T))
+floatof(::Type) = Real # fallback if type inference failed

test/Turing/inference/Inference.jl

@@ -424,36 +424,6 @@ for alg in (:HMC, :HMCDA, :NUTS, :SGLD, :SGHMC)
     @eval DynamicPPL.getspace(::$alg{<:Any, space}) where {space} = space
 end
 
-floatof(::Type{T}) where {T <: Real} = typeof(one(T)/one(T))
-floatof(::Type) = Real # fallback if type inference failed
-
-function get_matching_type(
-    spl::AbstractSampler, 
-    vi,
-    ::Type{T},
-) where {T}
-    return T
-end
-function get_matching_type(
-    spl::AbstractSampler, 
-    vi, 
-    ::Type{<:Union{Missing, AbstractFloat}},
-)
-    return Union{Missing, floatof(eltype(vi, spl))}
-end
-function get_matching_type(
-    spl::AbstractSampler,
-    vi,
-    ::Type{<:AbstractFloat},
-)
-    return floatof(eltype(vi, spl))
-end
-function get_matching_type(spl::AbstractSampler, vi, ::Type{<:Array{T,N}}) where {T,N}
-    return Array{get_matching_type(spl, vi, T), N}
-end
-function get_matching_type(spl::AbstractSampler, vi, ::Type{<:Array{T}}) where T
-    return Array{get_matching_type(spl, vi, T)}
-end
 function get_matching_type(
     spl::Sampler{<:Union{PG, SMC}}, 
     vi,

test/compiler.jl

@@ -267,6 +267,24 @@ end
         end
         model = testmodel(rand(10))
         @test all(z -> isapprox(z, 0; atol = 0.2), mean(model() for _ in 1:1000))
+
+        # test Turing#1464
+        @model function gdemo(x)
+            s ~ InverseGamma(2, 3)
+            m ~ Normal(0, sqrt(s))
+            for i in eachindex(x)
+                x[i] ~ Normal(m, sqrt(s))
+            end
+        end
+        x = [1.0, missing]
+        VarInfo(gdemo(x))
+        @test ismissing(x[2])
+
+        # https://github.com/TuringLang/Turing.jl/issues/1464#issuecomment-731153615
+        vi = VarInfo(gdemo(x))
+        @test haskey(vi.metadata, :x)
+        vi = VarInfo(gdemo(x))
+        @test haskey(vi.metadata, :x)
     end
     @testset "nested model" begin
         function makemodel(p)