From b478768602ee8d9aa68f62efc63a8e812c401c80 Mon Sep 17 00:00:00 2001
From: Felipe Noronha <felipenoris@gmail.com>
Date: Sat, 21 Aug 2021 12:45:09 -0300
Subject: [PATCH] avoid vector allocation when PartitionIterator is cut short

---
 base/iterators.jl | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/base/iterators.jl b/base/iterators.jl
index f9728cbbd0793..c0a68a36d836e 100644
--- a/base/iterators.jl
+++ b/base/iterators.jl
@@ -1191,11 +1191,11 @@ end
 struct IterationCutShort; end
 
 function iterate(itr::PartitionIterator, state...)
-    v = Vector{eltype(itr.c)}(undef, itr.n)
     # This is necessary to remember whether we cut the
     # last element short. In such cases, we do return that
     # element, but not the next one
     state === (IterationCutShort(),) && return nothing
+    v = Vector{eltype(itr.c)}(undef, itr.n)
     i = 0
     y = iterate(itr.c, state...)
     while y !== nothing