fix in(x, ::RectDiagonal) (#137)

Co-authored-by: Sheehan Olver <solver@mac.com>

Project.toml

@@ -1,6 +1,6 @@
 name = "FillArrays"
 uuid = "1a297f60-69ca-5386-bcde-b61e274b549b"
-version = "0.11.2"
+version = "0.11.3"
 
 [deps]
 LinearAlgebra = "37e2e46d-f89d-539d-b4ee-838fcccc9c8e"

src/FillArrays.jl

@@ -576,7 +576,11 @@ count(f, x::AbstractFill) = f(getindex_value(x)) ? length(x) : 0
 # in
 #########
 in(x, A::AbstractFill) = x == getindex_value(A)
-in(x, A::RectDiagonal) = iszero(x) || x in A.diag
+function in(x, A::RectDiagonal{<:Number})
+    any(iszero, size(A)) && return false # Empty matrix
+    all(isone, size(A)) && return x == A.diag[1] # A 1x1 matrix has only one element
+    x == zero(eltype(A)) || x in A.diag
+end
 
 include("fillalgebra.jl")
 include("fillbroadcast.jl")

test/runtests.jl

@@ -172,7 +172,20 @@ import FillArrays: AbstractFill, RectDiagonal, SquareEye
         end
         A = FillArrays.RectDiagonal([1, 2, 3])
         @test 3 in A
+        @test 0 in A
         @test !(4 in A)
+        A = FillArrays.RectDiagonal([1])
+        @test 1 in A
+        @test !(0 in A)
+        A = FillArrays.RectDiagonal([2], (1:1, 1:4))
+        @test 2 in A
+        @test 0 in A
+        @test !(1 in A)
+        @test !(Zeros(1,1) in A)
+        A = FillArrays.RectDiagonal(Int[])
+        @test !(0 in A)
+        A = FillArrays.RectDiagonal(Int[], (1:0, 1:4))
+        @test !(0 in A)
     end
 end