* benchmark/bm_hash_shift.rb: add benchmark for Hash#shift

* hash.c (rb_hash_shift): use st_shift if hash is not being iterated to
  delete element without iterating the whole hash.

* hash.c (shift_i): remove function

* include/ruby/st.h (st_shift): add st_shift function

* st.c (st_shift): ditto

[Bug #8312] [ruby-core:54524] Patch by funny-falcon

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@40457 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 10 insertions, 0 deletions

diff --git a/benchmark/bm_hash_shift.rb b/benchmark/bm_hash_shift.rb
new file mode 100644
index 0000000000..a645671a5b
--- /dev/null
+++ b/benchmark/bm_hash_shift.rb
@@ -0,0 +1,10 @@
+h = {}
+
+10000.times do |i|
+  h[i] = nil
+end
+
+50000.times do
+  k, v = h.shift
+  h[k] = v
+end