Some broadcast fixes (JuliaLang#18200)

* Fix JuliaLang#18176 (broadcast over mixtures of arrays and numeric scalars)

* Fix JuliaLang#17984 (broadcast behavior over empty arrays)

base/abstractarray.jl

@@ -1656,12 +1656,13 @@ function mapslices(f, A::AbstractArray, dims::AbstractVector)
 end
 
 # These are needed because map(eltype, As) is not inferrable
-promote_eltype_op(::Any) = (@_pure_meta; Bottom)
+promote_eltype_op(::Any) = (@_pure_meta; Any)
 promote_eltype_op(op, A) = (@_pure_meta; promote_op(op, eltype(A)))
 promote_eltype_op{T}(op, ::AbstractArray{T}) = (@_pure_meta; promote_op(op, T))
 promote_eltype_op{T}(op, ::AbstractArray{T}, A) = (@_pure_meta; promote_op(op, T, eltype(A)))
 promote_eltype_op{T}(op, A, ::AbstractArray{T}) = (@_pure_meta; promote_op(op, eltype(A), T))
 promote_eltype_op{R,S}(op, ::AbstractArray{R}, ::AbstractArray{S}) = (@_pure_meta; promote_op(op, R, S))
+promote_eltype_op(op, A, B) = (@_pure_meta; promote_op(op, eltype(A), eltype(B)))
 promote_eltype_op(op, A, B, C, D...) = (@_pure_meta; promote_eltype_op(op, promote_eltype_op(op, A, B), C, D...))
 
 ## 1 argument

base/broadcast.jl

@@ -213,7 +213,7 @@ function broadcast_t(f, ::Type{Any}, As...)
  shape = broadcast_shape(As...)
  iter = CartesianRange(shape)
  if isempty(iter)
- return similar(Array{Union{}}, shape)
+ return similar(Array{Any}, shape)
  end
  nargs = length(As)
  keeps, Idefaults = map_newindexer(shape, As)

test/abstractarray.jl

@@ -746,3 +746,12 @@ end
 @test ndims(Diagonal(rand(1:5,5))) == 2
 @test ndims(Diagonal{Float64}) == 2
 @test Base.elsize(Diagonal(rand(1:5,5))) == sizeof(Int)
+
+# Issue #17811
+let A17811 = Integer[]
+ I = [abs(x) for x in A17811]
+ @test isa(I, Array{Any,1})
+ push!(I, 1)
+ @test I == Any[1]
+ @test isa(map(abs, A17811), Array{Any,1})
+end

test/broadcast.jl

@@ -311,9 +311,19 @@ end
 let f17314 = x -> x < 0 ? false : x
  @test eltype(broadcast(f17314, 1:3)) === Int
  @test eltype(broadcast(f17314, -1:1)) === Integer
- @test eltype(broadcast(f17314, Int[])) === Union{}
+ @test eltype(broadcast(f17314, Int[])) === Any
 end
 let io = IOBuffer()
  broadcast(x->print(io,x), 1:5) # broadcast with side effects
  @test takebuf_array(io) == [0x31,0x32,0x33,0x34,0x35]
 end
+
+# Issue 18176
+let f18176(a, b, c) = a + b + c
+ @test f18176.(1.0:2, 3, 4) == f18176.(3.0, 1.0:2, 4.0) == broadcast(f18176, 3, 4, 1.0:2)
+end
+
+# Issue #17984
+let A17984 = []
+ @test isa(abs.(A17984), Array{Any,1})
+end

test/inference.jl

@@ -275,14 +275,6 @@ let f(x) = (x===nothing) ? 1 : 1.0
  @test Base.return_types(f, (Void,)) == Any[Int]
 end
 
-# Issue #17811
-let I = Integer[]
- I = abs(I)
- @test typeof(I) == Array{Any,1}
- push!(I, 1)
- @test I == Any[1]
-end
-
 # issue #16530
 type Foo16530a{dim}
  c::Vector{NTuple{dim, Float64}}