minor #4234 [7.3] Test that "LITERAL instanceof X" is valid (guilliamxavier)

This PR was merged into the 2.12 branch.

Discussion
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[7.3] Test that "LITERAL instanceof X" is valid

Refs #3697

Commits
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5390f84 [7.3] Test that "LITERAL instanceof X" is valid

Author: keradus

tests/Fixtures/Integration/misc/PHP7_3.test

@@ -37,6 +37,9 @@ is_countable($foo);
 // https://wiki.php.net/rfc/list_reference_assignment
 [$a, &$b] = $array; // `list_syntax` rule
 
+// https://github.com/php/php-src/pull/2978 instanceof now allows literals as the first operand (the result is always false).
+null instanceof \stdClass;
+
 // https://wiki.php.net/rfc/trailing-comma-function-calls Trailing commas in function and method calls are now allowed.
 foo(
     $arg,
@@ -91,6 +94,9 @@ IS_COUNTABLE($foo);
 // https://wiki.php.net/rfc/list_reference_assignment
 list($a, &$b) = $array; // `list_syntax` rule
 
+// https://github.com/php/php-src/pull/2978 instanceof now allows literals as the first operand (the result is always false).
+null instanceof \stdClass;
+
 // https://wiki.php.net/rfc/trailing-comma-function-calls Trailing commas in function and method calls are now allowed.
 foo(
     $arg,