Define push!, pop! and empty! for OffsetVector.

Author: fredrikekre

src/OffsetArrays.jl

@@ -195,7 +195,13 @@ Base.fill(x, inds::Tuple{UnitRange,Vararg{UnitRange}}) =
     fill!(OffsetArray{typeof(x)}(undef, inds), x)
 @inline Base.fill(x, ind1::UnitRange, inds::UnitRange...) = fill(x, (ind1, inds...))
 
+
+### Some mutating functions defined only for OffsetVector ###
+
 Base.resize!(A::OffsetVector, nl::Integer) = (resize!(A.parent, nl); A)
+Base.push!(A::OffsetVector, x...) = (push!(A.parent, x...); A)
+Base.pop!(A::OffsetVector) = pop!(A.parent)
+Base.empty!(A::OffsetVector) = (empty!(A.parent); A)
 
 ### Low-level utilities ###
 

test/runtests.jl

@@ -554,3 +554,24 @@ end
     O2[1, 1] = x + 1            # just a sanity check
     @test A[2, 2] == x + 1
 end
+
+@testset "mutating functions for OffsetVector" begin
+    # push!
+    o = OffsetVector(Int[], -1)
+    @test push!(o) === o
+    @test axes(o, 1) == 0:-1
+    @test push!(o, 1) === o
+    @test axes(o, 1) == 0:0
+    @test o[end] == 1
+    @test push!(o, 2, 3) === o
+    @test axes(o, 1) == 0:2
+    @test o[end-1:end] == [2, 3]
+    # pop!
+    o = OffsetVector([1, 2, 3], -1)
+    @test pop!(o) == 3
+    @test axes(o, 1) == 0:1
+    # empty!
+    o = OffsetVector([1, 2, 3], -1)
+    @test empty!(o) === o
+    @test axes(o, 1) == 0:-1
+end