Zend: Add zend_try_get_double

UPGRADING.INTERNALS

@@ -222,6 +222,9 @@ PHP 8.6 INTERNALS UPGRADE NOTES
   . Added zend_string_ends_with() and related variants.
   . Added trait support for internal classes.
   . Added do_php_cli().
+  . Added zval_try_get_double(), which converts a zval to a double and reports
+    conversion failures through a bool pointer, analogous to
+    zval_try_get_long().
 
 ========================
 2. Build system changes

Zend/zend_operators.c

@@ -1059,6 +1059,75 @@ ZEND_API double ZEND_FASTCALL zval_get_double_func(const zval *op) /* {{{ */
 }
 /* }}} */
 
+static zend_never_inline double ZEND_FASTCALL zval_try_get_double_func(const zval *op, bool *failed) /* {{{ */
+{
+	*failed = false;
+try_again:
+	switch (Z_TYPE_P(op)) {
+		case IS_NULL:
+		case IS_FALSE:
+			return 0.0;
+		case IS_TRUE:
+			return 1.0;
+		case IS_LONG:
+			return (double) Z_LVAL_P(op);
+		case IS_DOUBLE:
+			return Z_DVAL_P(op);
+		case IS_STRING:
+			{
+				uint8_t type;
+				zend_long lval;
+				double dval;
+				bool trailing_data = false;
+
+				/* For BC reasons we allow errors so that we can warn on leading numeric string */
+				type = is_numeric_string_ex(Z_STRVAL_P(op), Z_STRLEN_P(op), &lval, &dval,
+					/* allow errors */ true, NULL, &trailing_data);
+				if (type == 0) {
+					*failed = true;
+					return 0.0;
+				}
+				if (UNEXPECTED(trailing_data)) {
+					zend_error(E_WARNING, "A non-numeric value encountered");
+					if (UNEXPECTED(EG(exception))) {
+						*failed = true;
+						return 0.0;
+					}
+				}
+				return type == IS_LONG ? (double) lval : dval;
+			}
+		case IS_OBJECT:
+			{
+				zval dst;
+				if (Z_OBJ_HT_P(op)->cast_object(Z_OBJ_P(op), &dst, IS_DOUBLE) == FAILURE
+						|| EG(exception)) {
+					*failed = true;
+					return 0.0;
+				}
+				ZEND_ASSERT(Z_TYPE(dst) == IS_DOUBLE);
+				return Z_DVAL(dst);
+			}
+		case IS_RESOURCE:
+		case IS_ARRAY:
+			*failed = true;
+			return 0.0;
+		case IS_REFERENCE:
+			op = Z_REFVAL_P(op);
+			goto try_again;
+		default: ZEND_UNREACHABLE();
+	}
+}
+/* }}} */
+
+ZEND_API double ZEND_FASTCALL zval_try_get_double(const zval *op, bool *failed)
+{
+	if (EXPECTED(Z_TYPE_P(op) == IS_DOUBLE)) {
+		*failed = false;
+		return Z_DVAL_P(op);
+	}
+	return zval_try_get_double_func(op, failed);
+}
+
 static zend_always_inline zend_string* __zval_get_string_func(const zval *op, bool try) /* {{{ */
 {
 try_again:

Zend/zend_operators.h

@@ -323,6 +323,7 @@ ZEND_API void ZEND_FASTCALL convert_to_object(zval *op);
 ZEND_API zend_long    ZEND_FASTCALL zval_get_long_func(const zval *op, bool is_strict);
 ZEND_API zend_long    ZEND_FASTCALL zval_try_get_long(const zval *op, bool *failed);
 ZEND_API double       ZEND_FASTCALL zval_get_double_func(const zval *op);
+ZEND_API double       ZEND_FASTCALL zval_try_get_double(const zval *op, bool *failed);
 ZEND_API zend_string* ZEND_FASTCALL zval_get_string_func(const zval *op);
 ZEND_API zend_string* ZEND_FASTCALL zval_try_get_string_func(const zval *op);
 

ext/zend_test/test.c

@@ -1138,6 +1138,25 @@ static ZEND_FUNCTION(zend_test_refcount)
 	RETURN_LONG(Z_REFCOUNT_P(value));
 }
 
+static ZEND_FUNCTION(zend_test_zval_try_get_double)
+{
+	zval *value;
+
+	ZEND_PARSE_PARAMETERS_START(1, 1)
+		Z_PARAM_ZVAL(value)
+	ZEND_PARSE_PARAMETERS_END();
+
+	bool failed;
+	double result = zval_try_get_double(value, &failed);
+	if (UNEXPECTED(EG(exception))) {
+		RETURN_THROWS();
+	}
+
+	array_init(return_value);
+	add_assoc_double(return_value, "value", result);
+	add_assoc_bool(return_value, "failed", failed);
+}
+
 static ZEND_FUNCTION(zend_get_unit_enum)
 {
 	ZEND_PARSE_PARAMETERS_NONE();

ext/zend_test/test.stub.php

@@ -406,6 +406,8 @@ function zend_test_call_with_consumed_args(callable $cb, array $args, int $consu
 
     function zend_test_refcount(mixed $value): int {}
 
+    function zend_test_zval_try_get_double(mixed $value): array {}
+
     function zend_test_zend_ini_parse_quantity(string $str): int {}
     function zend_test_zend_ini_parse_uquantity(string $str): int {}
 

ext/zend_test/tests/zval_try_get_double.phpt

@@ -0,0 +1,127 @@
+--TEST--
+zval_try_get_double() conversion semantics
+--EXTENSIONS--
+zend_test
+--FILE--
+<?php
+
+foreach ([
+    null,
+    false,
+    true,
+    42,
+    42.5,
+    "42",
+    "42.5",
+    "1e3",
+    "not numeric",
+    [],
+    new FloatCastableNoOperations(42.5),
+    new LongCastableNoOperations(42),
+] as $value) {
+    var_dump(zend_test_zval_try_get_double($value));
+}
+
+$resource = fopen(__FILE__, 'r');
+var_dump(zend_test_zval_try_get_double($resource));
+
+var_dump(zend_test_zval_try_get_double("42 with trailing data"));
+
+set_error_handler(static function (int $errno, string $errstr): never {
+    throw new Exception($errstr);
+});
+try {
+    zend_test_zval_try_get_double("42 with trailing data");
+} catch (Throwable $e) {
+    echo $e::class, ': ', $e->getMessage(), "\n";
+}
+
+?>
+--EXPECTF--
+array(2) {
+  ["value"]=>
+  float(0)
+  ["failed"]=>
+  bool(false)
+}
+array(2) {
+  ["value"]=>
+  float(0)
+  ["failed"]=>
+  bool(false)
+}
+array(2) {
+  ["value"]=>
+  float(1)
+  ["failed"]=>
+  bool(false)
+}
+array(2) {
+  ["value"]=>
+  float(42)
+  ["failed"]=>
+  bool(false)
+}
+array(2) {
+  ["value"]=>
+  float(42.5)
+  ["failed"]=>
+  bool(false)
+}
+array(2) {
+  ["value"]=>
+  float(42)
+  ["failed"]=>
+  bool(false)
+}
+array(2) {
+  ["value"]=>
+  float(42.5)
+  ["failed"]=>
+  bool(false)
+}
+array(2) {
+  ["value"]=>
+  float(1000)
+  ["failed"]=>
+  bool(false)
+}
+array(2) {
+  ["value"]=>
+  float(0)
+  ["failed"]=>
+  bool(true)
+}
+array(2) {
+  ["value"]=>
+  float(0)
+  ["failed"]=>
+  bool(true)
+}
+array(2) {
+  ["value"]=>
+  float(42.5)
+  ["failed"]=>
+  bool(false)
+}
+array(2) {
+  ["value"]=>
+  float(0)
+  ["failed"]=>
+  bool(true)
+}
+array(2) {
+  ["value"]=>
+  float(0)
+  ["failed"]=>
+  bool(true)
+}
+
+Warning: A non-numeric value encountered in %s on line %d
+array(2) {
+  ["value"]=>
+  float(42)
+  ["failed"]=>
+  bool(false)
+}
+Exception: A non-numeric value encountered