RFC: array_change_keys

ext/opcache/Optimizer/zend_func_info.c

@@ -825,6 +825,7 @@ static const func_info_t func_infos[] = {
 	F1("array_pad",                    MAY_BE_NULL | MAY_BE_FALSE | MAY_BE_ARRAY | MAY_BE_ARRAY_KEY_ANY | MAY_BE_ARRAY_OF_REF | MAY_BE_ARRAY_OF_ANY),
 	F1("array_flip",                   MAY_BE_NULL | MAY_BE_ARRAY | MAY_BE_ARRAY_KEY_ANY | MAY_BE_ARRAY_OF_LONG | MAY_BE_ARRAY_OF_STRING),
 	F1("array_change_key_case",        MAY_BE_NULL | MAY_BE_ARRAY | MAY_BE_ARRAY_KEY_ANY | MAY_BE_ARRAY_OF_REF | MAY_BE_ARRAY_OF_ANY),
+	F1("array_change_keys",            MAY_BE_NULL | MAY_BE_ARRAY | MAY_BE_ARRAY_KEY_ANY | MAY_BE_ARRAY_OF_REF | MAY_BE_ARRAY_OF_ANY),
 	F1("array_rand",                   UNKNOWN_INFO),
 	F1("array_unique",                 MAY_BE_NULL | MAY_BE_ARRAY | MAY_BE_ARRAY_KEY_ANY | MAY_BE_ARRAY_OF_REF | MAY_BE_ARRAY_OF_ANY),
 	F1("array_intersect",              MAY_BE_NULL | MAY_BE_ARRAY | MAY_BE_ARRAY_KEY_ANY | MAY_BE_ARRAY_OF_REF | MAY_BE_ARRAY_OF_ANY),

ext/standard/array.c

@@ -3776,6 +3776,65 @@ PHP_FUNCTION(array_change_key_case)
 }
 /* }}} */
 
+/** {{{ proto array array_change_keys(array input, mixed callback)
+   Retuns an array with all keys modified by a callback */
+PHP_FUNCTION(array_change_keys)
+{
+    zval *array, *value, *params;
+    zval result;
+    zend_fcall_info fci;
+    zend_fcall_info_cache fci_cache = empty_fcall_info_cache;
+    zend_ulong num_key;
+    zend_string *str_key;
+
+    if (zend_parse_parameters(ZEND_NUM_ARGS(), "af", &array, &fci, &fci_cache) == FAILURE) {
+        return;
+    }
+
+    array_init_size(return_value, zend_hash_num_elements(Z_ARRVAL_P(array)));
+    params = (zval *)safe_emalloc(2, sizeof(zval), 0);
+
+    ZEND_HASH_FOREACH_KEY_VAL(Z_ARRVAL_P(array), num_key, str_key, value) {
+        fci.retval = &result;
+        fci.param_count = 2;
+        fci.params = params;
+        fci.no_separation = 0;
+
+        if (str_key) {
+            ZVAL_STR_COPY(&params[0], str_key);
+        } else {
+            ZVAL_LONG(&params[0], num_key);
+        }
+        ZVAL_COPY(&params[1], value);
+
+        if (zend_call_function(&fci, &fci_cache) != SUCCESS || Z_TYPE(result) == IS_UNDEF) {
+            zval_dtor(return_value);
+            zval_dtor(&params[0]);
+            zval_dtor(&params[1]);
+            efree(params);
+            RETURN_NULL();
+        }
+
+        zval_dtor(&params[0]);
+        zval_dtor(&params[1]);
+
+        if (Z_TYPE(result) == IS_STRING) {
+            value = zend_symtable_update(Z_ARRVAL_P(return_value), Z_STR(result), value);
+            zval_add_ref(value);
+        } else if (Z_TYPE(result) == IS_LONG) {
+            value = zend_hash_index_update(Z_ARRVAL_P(return_value), Z_LVAL(result), value);
+            zval_add_ref(value);
+        } else {
+            php_error_docref(NULL, E_WARNING, "New key should be either a string or an integer");
+        }
+
+        zval_ptr_dtor(&result);
+    } ZEND_HASH_FOREACH_END();
+
+    efree(params);
+}
+/* }}} */
+
 struct bucketindex {
 	Bucket b;
 	unsigned int i;

ext/standard/basic_functions.c

@@ -452,6 +452,11 @@ ZEND_BEGIN_ARG_INFO_EX(arginfo_array_change_key_case, 0, 0, 1)
 	ZEND_ARG_INFO(0, case)
 ZEND_END_ARG_INFO()
 
+ZEND_BEGIN_ARG_INFO_EX(arginfo_array_change_keys, 0, 0, 1)
+	ZEND_ARG_INFO(0, input) /* ARRAY_INFO(0, arg, 0) */
+	ZEND_ARG_INFO(0, callback)
+ZEND_END_ARG_INFO()
+
 ZEND_BEGIN_ARG_INFO_EX(arginfo_array_unique, 0, 0, 1)
 	ZEND_ARG_INFO(0, arg) /* ARRAY_INFO(0, arg, 0) */
 	ZEND_ARG_INFO(0, flags)
@@ -3312,6 +3317,7 @@ const zend_function_entry basic_functions[] = { /* {{{ */
 	PHP_FE(array_pad,														arginfo_array_pad)
 	PHP_FE(array_flip,														arginfo_array_flip)
 	PHP_FE(array_change_key_case,											arginfo_array_change_key_case)
+	PHP_FE(array_change_keys,											    arginfo_array_change_keys)
 	PHP_FE(array_rand,														arginfo_array_rand)
 	PHP_FE(array_unique,													arginfo_array_unique)
 	PHP_FE(array_intersect,													arginfo_array_intersect)

ext/standard/php_array.h

@@ -77,6 +77,7 @@ PHP_FUNCTION(array_reduce);
 PHP_FUNCTION(array_pad);
 PHP_FUNCTION(array_flip);
 PHP_FUNCTION(array_change_key_case);
+PHP_FUNCTION(array_change_keys);
 PHP_FUNCTION(array_rand);
 PHP_FUNCTION(array_unique);
 PHP_FUNCTION(array_intersect);

ext/standard/tests/array/array_change_keys.phpt

@@ -0,0 +1,132 @@
+--TEST--
+Test array_change_keys() function
+--FILE--
+<?php
+$arrayWithIntKeys = ['foo', 'bar'];
+$arrayWithStringKeys = ['foo' => 42, 'bar' => 3];
+$arrayWithMixedKeys = ['foo' => 42, 'bar'];
+
+echo "---Testing an empty array---\n";
+var_dump(array_change_keys([], function(){}));
+
+echo "---Numeric keys to numeric keys---\n";
+var_dump(array_change_keys($arrayWithIntKeys, function($k, $v) {
+    return $k * 10;
+}));
+
+echo "---Numeric keys to string keys---\n";
+var_dump(array_change_keys($arrayWithIntKeys, function($k, $v) {
+    return 'test:' . $k;
+}));
+
+echo "---String keys to numeric keys---\n";
+$i = 0;
+var_dump(array_change_keys($arrayWithIntKeys, function($k, $v) use (&$i) {
+    return $i++;
+}));
+
+echo "---String keys to string keys---\n";
+var_dump(array_change_keys($arrayWithStringKeys, function($k, $v) {
+    return 'test:' . $k;
+}));
+
+echo "---Mixed keys to numeric keys---\n";
+$i = 10;
+var_dump(array_change_keys($arrayWithMixedKeys, function($k, $v) use (&$i) {
+    return $i++;
+}));
+
+echo "---Mixed keys to string keys---\n";
+var_dump(array_change_keys($arrayWithMixedKeys, function($k, $v) {
+    return 'test:' . $k;
+}));
+
+echo "---Mixed keys to mixed keys---\n";
+var_dump(array_change_keys($arrayWithMixedKeys, function($k, $v) {
+    return is_int($k) ? 'baz' : 3;
+}));
+
+echo "---Test using a string as the callable---\n";
+// We can't reference 'md5' directly because it would get a truthy value in its second param,
+// This resulting in some raw bytes instead of a nice human-readable string.
+function use_md5_hash_as_key($k, $v) {
+    return md5($k);
+}
+var_dump(array_change_keys($arrayWithMixedKeys, 'use_md5_hash_as_key'));
+
+echo "---Test using the [\$obj, 'method'] callback syntax\n";
+$keyMaker = new class {
+    function getNewKey($k, $v) {
+        return md5($v);
+    }
+};
+var_dump(array_change_keys($arrayWithMixedKeys, [$keyMaker, 'getNewKey']));
+
+?>
+--EXPECTF--
+---Testing an empty array---
+array(0) {
+}
+---Numeric keys to numeric keys---
+array(2) {
+  [0]=>
+  string(3) "foo"
+  [10]=>
+  string(3) "bar"
+}
+---Numeric keys to string keys---
+array(2) {
+  ["test:0"]=>
+  string(3) "foo"
+  ["test:1"]=>
+  string(3) "bar"
+}
+---String keys to numeric keys---
+array(2) {
+  [0]=>
+  string(3) "foo"
+  [1]=>
+  string(3) "bar"
+}
+---String keys to string keys---
+array(2) {
+  ["test:foo"]=>
+  int(42)
+  ["test:bar"]=>
+  int(3)
+}
+---Mixed keys to numeric keys---
+array(2) {
+  [10]=>
+  int(42)
+  [11]=>
+  string(3) "bar"
+}
+---Mixed keys to string keys---
+array(2) {
+  ["test:foo"]=>
+  int(42)
+  ["test:0"]=>
+  string(3) "bar"
+}
+---Mixed keys to mixed keys---
+array(2) {
+  [3]=>
+  int(42)
+  ["baz"]=>
+  string(3) "bar"
+}
+---Test using a string as the callable---
+array(2) {
+  ["acbd18db4cc2f85cedef654fccc4a4d8"]=>
+  int(42)
+  ["cfcd208495d565ef66e7dff9f98764da"]=>
+  string(3) "bar"
+}
+---Test using the [$obj, 'method'] callback syntax
+array(2) {
+  ["a1d0c6e83f027327d8461063f4ac58a6"]=>
+  int(42)
+  ["37b51d194a7513e45b56f6524f2d51f2"]=>
+  string(3) "bar"
+}

ext/standard/tests/array/array_change_keys_variation1.phpt

@@ -0,0 +1,27 @@
+--TEST--
+Test array_change_keys() function with duplicate keys
+--FILE--
+<?php
+
+var_dump(array_change_keys([1, 2, 3], function(){ return 'foo'; }));
+
+var_dump(array_change_keys([1, 2, 3], function(){ return 99; }));
+
+var_dump(array_change_keys(range(1, 10), function($k, $v){ return $k % 2 ? 'foo' : 99; }));
+
+?>
+--EXPECTF--
+array(1) {
+  ["foo"]=>
+  int(3)
+}
+array(1) {
+  [99]=>
+  int(3)
+}
+array(2) {
+  [99]=>
+  int(9)
+  ["foo"]=>
+  int(10)
+}