Fix cropping when omitting a limit

src/lib/overloads.jl

@@ -162,15 +162,31 @@ Returns a subset of the argument layer, where the new limits are given by
 `left`, `right`, `top`, and `bottom`. Up to three of these can be omitted, and
 if so these limits will not be affected.
 """
-function Base.getindex(p::T; left::K=nothing, right::K=nothing, top::K=nothing, bottom::K=nothing) where {T <: SimpleSDMLayer, K <: Union{Nothing,AbstractFloat}}
-   imax = isnothing(right) ? p.right : match_longitude(p, right)
-   imin = isnothing(left) ? p.left : match_longitude(p, left)
-   jmax = isnothing(top) ? p.top : match_latitude(p, top)
-   jmin = isnothing(bottom) ? p.bottom : match_latitude(p, bottom)
+function Base.getindex(p::T; left::Union{N,A}=nothing, right::Union{N,A}=nothing, top::Union{N,A}=nothing, bottom::Union{N,A}=nothing) where {T <: SimpleSDMLayer, N <: Nothing, A <: AbstractFloat}
+   imax = match_longitude(p, isnothing(right) ? p.right : right)
+   imin = match_longitude(p, isnothing(left) ? p.left : left)
+   jmax = match_latitude(p, isnothing(top) ? p.top : top)
+   jmin = match_latitude(p, isnothing(bottom) ? p.bottom : bottom)
    any(isnan.([imin, imax, jmin, jmax])) && throw(ArgumentError("Unable to extract, coordinates outside of range"))
    return p[jmin:jmax, imin:imax]
 end
 
+"""
+    Base.getindex(p::T, n::NT) where {T <: SimpleSDMLayer, NT <: NamedTuple}
+
+Returns a subset of the argument layer, where the new limits are given in
+a NamedTuple by `left`, `right`, `top`, and `bottom`, in any order. Up to 
+three of these can be omitted, and if so these limits will not be affected.
+"""
+
+function Base.getindex(p::T, n::NT) where {T <: SimpleSDMLayer, NT <: NamedTuple}
+    l = isdefined(n, :left) ? n.left : nothing
+    r = isdefined(n, :right) ? n.right : nothing
+    t = isdefined(n, :top) ? n.top : nothing
+    b = isdefined(n, :bottom) ? n.bottom : nothing
+    Base.getindex(p; left = l, right = r, top = t, bottom = b)
+end
+
 """
     Base.getindex(p1::T1, p2::T2) where {T1 <: SimpleSDMLayer, T2 <: SimpleSDMLayer}
 

test/overloads.jl

@@ -26,6 +26,15 @@ end
 @test S[left=0.2, right=0.6, bottom=0.5, top=1.0].right ≈ 0.6
 @test S[left=0.2, right=0.6, bottom=0.5, top=1.0].left ≈ 0.2
 
+@test typeof(S[left=0.2, bottom=0.5]) == typeof(S)
+@test S[left=0.2, bottom=0.5].top ≈ 1.0
+@test S[left=0.2, bottom=0.5].bottom ≈ 0.4
+@test S[left=0.2, bottom=0.5].right ≈ 1.0
+@test S[left=0.2, bottom=0.5].left ≈ 0.2
+
+C = (left=0.2, bottom=0.5)
+@test typeof(S[C]) == typeof(S)
+
 Y = SimpleSDMResponse(zeros(Float64, (5,5)), 0.0, 1.0, 0.0, 1.0)
 Y[0.1,0.1] = 0.2
 @test Y[0.1,0.1] == 0.2