Code completion result for source line:
$instance->testUnionTy|pe(1, null, null);
(QueryType=COMPLETION, prefixSearch=false, caseSensitive=true)
METHOD     testUnionType(int|float $param  [PUBLIC]   TestClass

Documentation:

testUnionType


Parameters:

 int | float$param1PHPDoc not found
 Foo | Bar$param2PHPDoc not found
 \Test\Foo | \Test\Bar$param3PHPDoc not found

Returns:

Type:int | Foo | \Test\Bar