Function barrier in PiecewiseSpace (#200)

* function barrier in `PiecewiseSpace`

* Add test

* improve `promotespaces` performance

* version bump to v0.7.1

Author: jishnub

Project.toml

@@ -1,6 +1,6 @@
 name = "ApproxFunBase"
 uuid = "fbd15aa5-315a-5a7d-a8a4-24992e37be05"
-version = "0.7.0"
+version = "0.7.1"
 
 [deps]
 AbstractFFTs = "621f4979-c628-5d54-868e-fcf4e3e8185c"

src/ApproxFunBase.jl

@@ -105,6 +105,8 @@ end
 # assert that the conversion succeeds. This helps with inference as well as sanity
 strictconvert(T::Type, x) = convert(T, x)::T
 
+uniontypedvec(A, B) = Union{typeof(A), typeof(B)}[A, B]
+
 include("LinearAlgebra/LinearAlgebra.jl")
 include("Fun.jl")
 include("onehotvector.jl")

src/Operators/spacepromotion.jl

@@ -156,7 +156,7 @@ function promotespaces(A::Operator,B::Operator)
     if spacescompatible(A,B)
         A,B
     else
-        tuple(promotespaces([A,B])...)
+        tuple(Vec{2}(promotespaces(uniontypedvec(A,B)))...)
     end
 end
 

src/Spaces/SumSpace.jl

@@ -61,12 +61,14 @@ struct PiecewiseSpace{SV,D<:UnionDomain,R} <: DirectSumSpace{SV,D,R}
         new{SV,D,R}(sp)
 end
 
-function PiecewiseSpace(spin::Tuple)
-    sp=tuple(union(spin)...)  # remove duplicates
-
+function _PiecewiseSpace(sp)
     PiecewiseSpace{typeof(sp),typeof(UnionDomain(map(domain,sp))),
                    mapreduce(rangetype,promote_type,sp)}(sp)
 end
+function PiecewiseSpace(spin::Tuple)
+    sp=tuple(union(spin)...)  # remove duplicates
+    _PiecewiseSpace(sp)
+end
 
 PiecewiseSpace(spin::Set) = PiecewiseSpace(collect(spin))
 

test/SpacesTest.jl

@@ -140,6 +140,15 @@ using LinearAlgebra
             @test CM == Diagonal(1:3)
             @test size(C[1:0, 1:0]) == (0, 0)
         end
+
+        @testset "broadcast" begin
+            f = Fun(PointSpace(1:3), 1:3)
+            g = f^2
+            h = f.^2
+            for i in 1:3
+                @test g(i) == h(i)
+            end
+        end
     end
 
     @testset "DiracSpace" begin