Add new flag ARRAY_FILTER_PACK_RESULT

ext/standard/array.c

@@ -6511,13 +6511,19 @@ PHP_FUNCTION(array_filter)
 		Z_PARAM_LONG(use_type)
 	ZEND_PARSE_PARAMETERS_END();
 
+	bool pack_result = use_type & ARRAY_FILTER_PACK_RESULT;
+	use_type &= ~ARRAY_FILTER_PACK_RESULT;
+
 	switch (use_type) {
 		case ARRAY_FILTER_USE_VALUE:
 		case ARRAY_FILTER_USE_BOTH:
 		case ARRAY_FILTER_USE_KEY:
 			break;
 		default:
-			zend_argument_value_error(3, "must be one of ARRAY_FILTER_USE_VALUE, ARRAY_FILTER_USE_KEY, or ARRAY_FILTER_USE_BOTH");
+			zend_argument_value_error(
+				3,
+				"must be one of ARRAY_FILTER_USE_VALUE, ARRAY_FILTER_USE_KEY, or ARRAY_FILTER_USE_BOTH (optionally combined with ARRAY_FILTER_PACK_RESULT)"
+			);
 		RETURN_THROWS();
 	}
 
@@ -6567,7 +6573,9 @@ PHP_FUNCTION(array_filter)
 			continue;
 		}
 
-		if (string_key) {
+		if (pack_result) {
+			operand = zend_hash_next_index_insert(Z_ARRVAL_P(return_value), operand);
+		} else if (string_key) {
 			operand = zend_hash_add_new(Z_ARRVAL_P(return_value), string_key, operand);
 		} else {
 			operand = zend_hash_index_add_new(Z_ARRVAL_P(return_value), num_key, operand);

ext/standard/basic_functions.stub.php

@@ -132,6 +132,11 @@ enum SortDirection {
  * @cvalue ARRAY_FILTER_USE_KEY
  */
 const ARRAY_FILTER_USE_KEY = UNKNOWN;
+/**
+ * @var int
+ * @cvalue ARRAY_FILTER_PACK_RESULT
+ */
+const ARRAY_FILTER_PACK_RESULT = UNKNOWN;
 
 /* assert.c */
 

ext/standard/php_array.h

@@ -60,6 +60,7 @@ PHPAPI bool php_array_pick_keys(php_random_algo_with_state engine, zval *input,
 #define ARRAY_FILTER_USE_VALUE	0
 #define ARRAY_FILTER_USE_BOTH	1
 #define ARRAY_FILTER_USE_KEY	2
+#define ARRAY_FILTER_PACK_RESULT 4
 
 extern PHPAPI zend_class_entry *sort_direction_ce;
 

ext/standard/tests/array/array_filter_invalid_mode.phpt

@@ -12,5 +12,5 @@ try {
 echo "Done"
 ?>
 --EXPECT--
-ValueError: array_filter(): Argument #3 ($mode) must be one of ARRAY_FILTER_USE_VALUE, ARRAY_FILTER_USE_KEY, or ARRAY_FILTER_USE_BOTH
+ValueError: array_filter(): Argument #3 ($mode) must be one of ARRAY_FILTER_USE_VALUE, ARRAY_FILTER_USE_KEY, or ARRAY_FILTER_USE_BOTH (optionally combined with ARRAY_FILTER_PACK_RESULT)
 Done

ext/standard/tests/array/array_filter_pack.phpt

@@ -0,0 +1,121 @@
+--TEST--
+array_filter() tests with ARRAY_FILTER_PACK_RESULT
+--FILE--
+<?php
+
+$array1 = [false, null, true, '', 'foo', 0, 123];
+var_dump( array_filter( $array1 ) );
+var_dump( array_filter( $array1, null, ARRAY_FILTER_PACK_RESULT ) );
+
+$array2 = [
+    'index 0 means false key',
+    '' => 'false key empty string',
+    false,
+];
+// to filter based on a truthy key requires an explicit callback
+var_dump( array_filter( $array2, fn ($v) => $v, ARRAY_FILTER_USE_KEY ) );
+var_dump( array_filter( $array2, fn ($v) => $v, ARRAY_FILTER_USE_KEY | ARRAY_FILTER_PACK_RESULT ) );
+
+$array3 = [
+    'key1' => true,
+    'key2' => false,
+    'key3' => 123,
+];
+function filter( $value, $key ) {
+    $value = var_export( $value, true );
+    echo 'Filter: $key => $value\n';
+    return true;
+}
+var_dump( array_filter( $array3, filter(...), ARRAY_FILTER_USE_BOTH ) );
+var_dump( array_filter( $array3, filter(...), ARRAY_FILTER_USE_BOTH | ARRAY_FILTER_PACK_RESULT ) );
+
+$array4 = [
+    123,
+    true,
+    false,
+    (object)[],
+    [],
+    456,
+    '123',
+];
+var_dump( array_filter( $array4, is_int(...) ) );
+var_dump( array_filter( $array4, is_int(...), ARRAY_FILTER_PACK_RESULT ) );
+
+$array4 = [
+    'first int' => 123,
+    'true' => true,
+    'false' => false,
+    'object' => (object)[],
+    'array' => [],
+    'second int' => 456,
+    'int-looking string' => '123',
+];
+var_dump( array_filter( $array4, is_int(...) ) );
+var_dump( array_filter( $array4, is_int(...), ARRAY_FILTER_PACK_RESULT ) );
+
+?>
+--EXPECT--
+array(3) {
+  [2]=>
+  bool(true)
+  [4]=>
+  string(3) "foo"
+  [6]=>
+  int(123)
+}
+array(3) {
+  [0]=>
+  bool(true)
+  [1]=>
+  string(3) "foo"
+  [2]=>
+  int(123)
+}
+array(1) {
+  [1]=>
+  bool(false)
+}
+array(1) {
+  [0]=>
+  bool(false)
+}
+Filter: $key => $value\nFilter: $key => $value\nFilter: $key => $value\narray(3) {
+  ["key1"]=>
+  bool(true)
+  ["key2"]=>
+  bool(false)
+  ["key3"]=>
+  int(123)
+}
+Filter: $key => $value\nFilter: $key => $value\nFilter: $key => $value\narray(3) {
+  [0]=>
+  bool(true)
+  [1]=>
+  bool(false)
+  [2]=>
+  int(123)
+}
+array(2) {
+  [0]=>
+  int(123)
+  [5]=>
+  int(456)
+}
+array(2) {
+  [0]=>
+  int(123)
+  [1]=>
+  int(456)
+}
+array(2) {
+  ["first int"]=>
+  int(123)
+  ["second int"]=>
+  int(456)
+}
+array(2) {
+  [0]=>
+  int(123)
+  [1]=>
+  int(456)
+}