Add Internals::HvREHASH to expose the rehashing flag

t/op/hash.t tests that pathological data triggers rehashing

p4raw-id: //depot/perl@21604

1 files changed, 27 insertions, 0 deletions

diff --git a/t/op/hash.t b/t/op/hash.t
new file mode 100644
index 0000000000..3beae8432a
--- /dev/null
+++ b/t/op/hash.t
@@ -0,0 +1,27 @@
+#!./perl -w
+
+BEGIN {
+    chdir 't' if -d 't';
+    @INC = '../lib';
+    require './test.pl';
+}
+
+use strict;
+
+plan tests => 3;
+
+my %h;
+
+ok (!Internals::HvREHASH(%h), "hash doesn't start with rehash flag on");
+
+foreach (1..10) {
+  $h{"\0"x$_}++;
+}
+
+ok (!Internals::HvREHASH(%h), "10 entries doesn't trigger rehash");
+
+foreach (11..20) {
+  $h{"\0"x$_}++;
+}
+
+ok (Internals::HvREHASH(%h), "20 entries triggers rehash");