Pretty-printing of FunctionProducts

Author: jagot

src/densities.jl

@@ -80,6 +80,22 @@ end
 
 Base.eltype(ρ::FunctionProduct{<:Any,T}) where T = T
 
+function Base.show(io::IO, ρ::FunctionProduct{Conjugated, T}) where {Conjugated,T}
+    mL = size(ρ.L,2)
+    mR = size(ρ.R,2)
+    mρ = length(ρ.ρ)
+    write(io, "$(mL) .* $(mR) -> $(mρ) FunctionProduct $T")
+    Conjugated && write(io, ", conjugated (<=> Density)")
+end
+
+function Base.show(io::IO, ::MIME"text/plain", ρ::FunctionProduct)
+    show(io, ρ)
+    write(io, "; L .* R -> R, with\n  L: ")
+    show(io, ρ.L)
+    write(io, "\n  R: ")
+    show(io, ρ.R)
+end
+
 """
     copyto!(ρ::FunctionProduct{Conjugated}, f::AbstractVector, g::AbstractVector) where Conjugated
 

test/densities.jl

@@ -42,4 +42,29 @@
 
         @test ch2 ≈ ch atol=1e-14 rtol=rtol
     end
+
+    @testset "Pretty-printing" begin
+        R = FiniteDifferences(99, 0.1)
+        u = R*rand(size(R,2))
+        v = R*rand(size(R,2))
+        ρ = Density(u, v)
+        fp = FunctionProduct{false}(u, v)
+
+        @test string(ρ) == "99 .* 99 -> 99 FunctionProduct Float64, conjugated (<=> Density)"
+        @test string(fp) == "99 .* 99 -> 99 FunctionProduct Float64"
+
+        buf = IOBuffer()
+        show(buf, MIME"text/plain"(), ρ)
+        @test String(take!(buf)) == """
+            99 .* 99 -> 99 FunctionProduct Float64, conjugated (<=> Density); L .* R -> R, with
+              L: $(string(R))
+              R: $(string(R))"""
+
+        buf = IOBuffer()
+        show(buf, MIME"text/plain"(), fp)
+        @test String(take!(buf)) == """
+            99 .* 99 -> 99 FunctionProduct Float64; L .* R -> R, with
+              L: $(string(R))
+              R: $(string(R))"""
+    end
 end