[VarExporter] Fix exporting default values involving global constants

Author: kylekatarnls

ProxyHelper.php

@@ -219,12 +219,14 @@ public static function exportSignature(\ReflectionFunctionAbstract $function, bo
         $args = '';
         $param = null;
         $parameters = [];
+        $namespace = $function instanceof \ReflectionMethod ? $function->class : $function->getNamespaceName().'\\';
+        $namespace = substr($namespace, 0, strrpos($namespace, '\\') ?: 0);
         foreach ($function->getParameters() as $param) {
             $parameters[] = ($param->getAttributes(\SensitiveParameter::class) ? '#[\SensitiveParameter] ' : '')
                 .($withParameterTypes && $param->hasType() ? self::exportType($param).' ' : '')
                 .($param->isPassedByReference() ? '&' : '')
                 .($param->isVariadic() ? '...' : '').'$'.$param->name
-                .($param->isOptional() && !$param->isVariadic() ? ' = '.self::exportDefault($param) : '');
+                .($param->isOptional() && !$param->isVariadic() ? ' = '.self::exportDefault($param, $namespace) : '');
             if ($param->isPassedByReference()) {
                 $byRefIndex = 1 + $param->getPosition();
             }
@@ -333,7 +335,7 @@ private static function exportPropertyScopes(string $parent): string
         return $propertyScopes;
     }
 
-    private static function exportDefault(\ReflectionParameter $param): string
+    private static function exportDefault(\ReflectionParameter $param, $namespace): string
     {
         $default = rtrim(substr(explode('$'.$param->name.' = ', (string) $param, 2)[1] ?? '', 0, -2));
 
@@ -347,26 +349,40 @@ private static function exportDefault(\ReflectionParameter $param): string
         $regexp = "/(\"(?:[^\"\\\\]*+(?:\\\\.)*+)*+\"|'(?:[^'\\\\]*+(?:\\\\.)*+)*+')/";
         $parts = preg_split($regexp, $default, -1, \PREG_SPLIT_DELIM_CAPTURE | \PREG_SPLIT_NO_EMPTY);
 
-        $regexp = '/([\[\( ]|^)([a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*+(?:\\\\[a-zA-Z0-9_\x7f-\xff]++)*+)(?!: )/';
+        $regexp = '/([\[\( ]|^)([a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*+(?:\\\\[a-zA-Z0-9_\x7f-\xff]++)*+)(\(?)(?!: )/';
         $callback = (false !== strpbrk($default, "\\:('") && $class = $param->getDeclaringClass())
             ? fn ($m) => $m[1].match ($m[2]) {
                 'new', 'false', 'true', 'null' => $m[2],
                 'NULL' => 'null',
                 'self' => '\\'.$class->name,
                 'namespace\\parent',
                 'parent' => ($parent = $class->getParentClass()) ? '\\'.$parent->name : 'parent',
-                default => '\\'.$m[2],
-            }
+                default => self::exportSymbol($m[2], '(' !== $m[3], $namespace),
+            }.$m[3]
             : fn ($m) => $m[1].match ($m[2]) {
                 'new', 'false', 'true', 'null', 'self', 'parent' => $m[2],
                 'NULL' => 'null',
-                default => '\\'.$m[2],
-            };
+                default => self::exportSymbol($m[2], '(' !== $m[3], $namespace),
+            }.$m[3];
 
         return implode('', array_map(fn ($part) => match ($part[0]) {
             '"' => $part, // for internal classes only
             "'" => false !== strpbrk($part, "\\\0\r\n") ? '"'.substr(str_replace(['$', "\0", "\r", "\n"], ['\$', '\0', '\r', '\n'], $part), 1, -1).'"' : $part,
             default => preg_replace_callback($regexp, $callback, $part),
         }, $parts));
     }
+
+    private static function exportSymbol(string $symbol, bool $mightBeRootConst, string $namespace): string
+    {
+        if (!$mightBeRootConst
+            || false === ($ns = strrpos($symbol, '\\'))
+            || substr($symbol, 0, $ns) !== $namespace
+            || \defined($symbol)
+            || !\defined(substr($symbol, $ns + 1))
+        ) {
+            return '\\'.$symbol;
+        }
+
+        return '\\'.substr($symbol, $ns + 1);
+    }
 }

Tests/ProxyHelperTest.php

@@ -37,6 +37,7 @@ public static function provideExportSignature()
             $expected = str_replace(['.', ' .  .  . ', '\'$a\', \'$a\n\', "\$a\n"'], [' . ', '...', '\'$a\', "\$a\\\n", "\$a\n"'], $expected);
             $expected = str_replace('Bar', '\\'.Bar::class, $expected);
             $expected = str_replace('self', '\\'.TestForProxyHelper::class, $expected);
+            $expected = str_replace('= [namespace\\M_PI, new M_PI]', '= [\M_PI, new \Symfony\Component\VarExporter\Tests\M_PI()]', $expected);
 
             yield [$expected, $method];
         }
@@ -237,6 +238,10 @@ public static function foo8()
     public function foo9($a = self::BOB, $b = ['$a', '$a\n', "\$a\n"], $c = ['$a', '$a\n', "\$a\n", new \stdClass()])
     {
     }
+
+    public function foo10($a = [namespace\M_PI, new M_PI()])
+    {
+    }
 }
 
 interface TestForProxyHelperInterface1