Add hash_equals polyfill and related tests

1 files changed, 15 insertions, 0 deletions

diff --git a/tests/HelpersTest.php b/tests/HelpersTest.php
new file mode 100644
index 0000000..141e604
--- /dev/null
+++ b/tests/HelpersTest.php
@@ -0,0 +1,15 @@
+<?php
+
+use PHPUnit\Framework\TestCase;
+
+class HelpersTest extends TestCase
+{
+    function test_constant_time_compare()
+    {
+        $this->assertTrue(_hash_equals('abc', 'abc'));
+        $this->assertFalse(_hash_equals('abc', 'ab'));
+        $this->assertFalse(_hash_equals('ab', 'abc'));
+        $this->assertFalse(_hash_equals('abcd', 'adbc'));
+        $this->assertFalse(_hash_equals(0, 0));
+    }
+}