Doc #76511 [Com]: array_merge_recursive() treats root indexed array keys differently than sub-arr

Edit report at https://bugs.php.net/bug.php?id=76511&edit=1 ID: 76511 Comment by: german dot drulyk at gmail dot com Reported by: german dot drulyk at gmail dot com Summary: array_merge_recursive() treats root indexed array keys differently than sub-arr Status: Verified Type: Documentation Problem Package: Arrays related Operating System: https://3v4l.org/ PHP Version: Irrelevant Block user comment: N Private report: N New Comment: I am not criticizing the decision to renumber the root array to start at zero. The purpose of this report is to show the array_merge_recursive() treats sub-array indexes differently than the root array. To clarify: Why did the sub-array keys retain 4 and 5 even though the root array went 0 and 1 This seems to be inconsistent behavior. Previous Comments: ------------------------------------------------------------------------ [2018-06-21 12:54:45] cmb@php.net For reference: <https://3v4l.org/qpnVs>. The docs on array_merge() are pretty clear in this regard[1]: | If, however, the arrays contain numeric keys, the later value | will not overwrite the original value, but will be appended. | | Values in the input array with numeric keys will be renumbered | with incrementing keys starting from zero in the result array. The latter info is missing from the array_merge_recursive() docs, though, wrt. the toplevel array. [1] <http://php.net/manual/en/function.array-merge.php> ------------------------------------------------------------------------ [2018-06-21 12:32:20] german dot drulyk at gmail dot com Description: ------------ I am not sure which behavior is the bug but the root array gets re-indexed to 0 and 1 and the array at position "k" goes from 4 to 5. array_merge() exhibits the same behavior with the root array. Test script: --------------- $arr1 = array( 4 => 'a', 'k' => array( 4 => 'a' ) ); $arr2 = array( 5 => 'b', 'k' => array( 5 => 'b' ) ); $arr3 = array_merge_recursive( $arr1, $arr2 ); var_dump( $arr3 ); Expected result: ---------------- array(3) { [0]=> // Should this be 4? string(1) "a" ["k"]=> array(2) { [4]=> // or should this be 0? string(1) "a" [5]=> // or should this be 1? string(1) "b" } [1]=> // Should this be 5? string(1) "b" } Actual result: -------------- array(3) { [0]=> string(1) "a" ["k"]=> array(2) { [4]=> string(1) "a" [5]=> string(1) "b" } [1]=> string(1) "b" } ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=76511&edit=1