Add Base.pop! method to StructVector (#190)

* Add Base.pop! method to StructVector

Exact implementation could vary from this one, but Base.pop! is desirable to have as a utility method, especially if Base.push! is already there.

* Added tests.

* Update src/structarray.jl

Simplified implementation

Co-authored-by: Pietro Vertechi <pietro.vertechi@protonmail.com>

* Fixed tests

* Formatting

Co-authored-by: Pietro Vertechi <pietro.vertechi@protonmail.com>

Author: saolof

src/structarray.jl

@@ -365,6 +365,11 @@ function Base.push!(s::StructVector, vals)
     return s
 end
 
+function Base.pop!(s::StructVector{T}) where T
+    t = map(pop!, components(s))
+    return createinstance(T, t...)
+end
+
 function Base.append!(s::StructVector, vals::StructVector)
     foreachfield(append!, s, vals)
     return s

test/runtests.jl

@@ -222,6 +222,9 @@ end
     push!(t, (1, 2))
     @test getproperty(t, 1) == [2, 1]
     @test getproperty(t, 2) == [3.0, 2.0]
+    @test pop!(t) == (1, 2.0)
+    @test getproperty(t, 1) == [2]
+    @test getproperty(t, 2) == [3.0]
 end
 
 @testset "constructor from slices" begin
@@ -309,6 +312,9 @@ end
 
 @testset "concat" begin
     t = StructArray{Pair}(([3, 5], ["a", "b"]))
+    push!(t, (2 => "d"))
+    @test t == StructArray{Pair}(([3, 5, 2], ["a", "b", "d"]))
+    @test pop!(t) == (2 => "d")
     push!(t, (2 => "c"))
     @test t == StructArray{Pair}(([3, 5, 2], ["a", "b", "c"]))
     append!(t, t)