Bug #78164 [NEW]: array_diff_key won't return diff while it shoud in a very specific case

From: joseph42379 at gmail dot com Operating system: Mac OS PHP version: 7.1Git-2019-06-14 (snap) Package: Unknown/Other Function Bug Type: Bug Bug description:array_diff_key won't return diff while it shoud in a very specific case Description: ------------ Turns out if the first argument(array) provided is smaller than the second one, it always return the empty array. Test script: --------------- <? var_dump( array_diff_key( [ 'a'=>1, ], [ 'a'=>1, 'b'=>1 ] ) ); Expected result: ---------------- array(0) { ["b"]=> int(1) } Actual result: -------------- array(0) { } -- Edit bug report at https://bugs.php.net/bug.php?id=78164&edit=1 -- Try a snapshot (PHP 5.4): https://bugs.php.net/fix.php?id=78164&r=trysnapshot54 Try a snapshot (PHP 5.5): https://bugs.php.net/fix.php?id=78164&r=trysnapshot55 Try a snapshot (trunk): https://bugs.php.net/fix.php?id=78164&r=trysnapshottrunk Fixed in SVN: https://bugs.php.net/fix.php?id=78164&r=fixed Fixed in release: https://bugs.php.net/fix.php?id=78164&r=alreadyfixed Need backtrace: https://bugs.php.net/fix.php?id=78164&r=needtrace Need Reproduce Script: https://bugs.php.net/fix.php?id=78164&r=needscript Try newer version: https://bugs.php.net/fix.php?id=78164&r=oldversion Not developer issue: https://bugs.php.net/fix.php?id=78164&r=support Expected behavior: https://bugs.php.net/fix.php?id=78164&r=notwrong Not enough info: https://bugs.php.net/fix.php?id=78164&r=notenoughinfo Submitted twice: https://bugs.php.net/fix.php?id=78164&r=submittedtwice register_globals: https://bugs.php.net/fix.php?id=78164&r=globals PHP 4 support discontinued: https://bugs.php.net/fix.php?id=78164&r=php4 Daylight Savings: https://bugs.php.net/fix.php?id=78164&r=dst IIS Stability: https://bugs.php.net/fix.php?id=78164&r=isapi Install GNU Sed: https://bugs.php.net/fix.php?id=78164&r=gnused Floating point limitations: https://bugs.php.net/fix.php?id=78164&r=float No Zend Extensions: https://bugs.php.net/fix.php?id=78164&r=nozend MySQL Configuration Error: https://bugs.php.net/fix.php?id=78164&r=mysqlcfg