Revert "Improve copyto! for short heterogeneous tuples (#39035)" (#39128)

This reverts commit b00e9f0, which has a 1/64 chance of failing tests.

Author: vtjnash

base/abstractarray.jl

@@ -831,14 +831,12 @@ end
 
 ## from general iterable to any array
 
-@noinline throw_dest_too_short() =
-    throw(ArgumentError("destination has fewer elements than required"))
-
 function copyto!(dest::AbstractArray, src)
     destiter = eachindex(dest)
     y = iterate(destiter)
     for x in src
-        y === nothing && throw_dest_too_short()
+        y === nothing &&
+            throw(ArgumentError("destination has fewer elements than required"))
         dest[y[1]] = x
         y = iterate(destiter, y[2])
     end

base/ntuple.jl

@@ -91,47 +91,3 @@ end
         (t..., fill(val, N-M)...)
     end
 end
-
-# Specializations for copyto! of various `NTuple`s
-function check_inds_compatible(dest::AbstractArray, src::Tuple)
-    length(dest) >= length(src) || throw_dest_too_short()
-end
-
-function _copyto_generated!(dest::AbstractArray, src::NTuple{N, Any}) where N
-    if @generated
-        ret = quote
-            check_inds_compatible(dest, src)
-            idxs = eachindex(dest)
-        end
-        state = ()
-        for n in 1:N
-            append!(ret.args, (quote
-                ind, state = iterate(idxs, $(state...))
-                @inbounds dest[ind] = src[$n]
-            end).args)
-            state = (:state,)
-        end
-        push!(ret.args, :(return dest))
-        ret
-    else
-        length(src) == 0 && return dest
-        return copyto!(dest, firstindex(dest), src, firstindex(src))
-    end
-end
-
-# Non-homogeneous tuples
-function copyto!(dest::AbstractArray, src::Tuple)
-    if length(src) < 10
-        # Manual optimization for short tuples
-        # TODO: Better support for homogeneous tuple tails
-        return _copyto_generated!(dest, src)
-    else
-        return copyto!(dest, firstindex(dest), src, firstindex(src))
-    end
-end
-
-# Specialization for homogeneous tuples
-function copyto!(dest::AbstractArray, src::Tuple{Vararg{T}} where T)
-    length(src) == 0 && return dest
-    copyto!(dest, firstindex(dest), src, firstindex(src))
-end

test/abstractarray.jl

@@ -1263,13 +1263,3 @@ Base.pushfirst!(tpa::TestPushArray{T}, a::T) where T = pushfirst!(tpa.data, a)
     pushfirst!(tpa, 6, 5, 4, 3, 2)
     @test tpa.data == reverse(collect(1:6))
 end
-
-@testset "copyto! with tuple" begin
-    randtype(n) = rand(Bool) ? 1.0 : 2
-    @test copyto!(fill(0.0, 100), ntuple(randtype, 100))[end] != 0.0
-    @test copyto!(fill(0.0, 100), ntuple(x->1.0, 100))[end] != 0.0
-    @test copyto!(fill(0.0, 100), ntuple(randtype, 50))[end] == 0.0
-    @test_throws BoundsError copyto!(fill(0.0, 50), ntuple(randtype, 100))
-    @test_throws BoundsError copyto!(fill(0.0, 50), ntuple(x->1.0, 100))
-    @test_throws ArgumentError copyto!(fill(0.0, 5), ntuple(randtype, 7))
-end