Add tests for null cases

Author: kylekatarnls

ext/standard/tests/math/clamp.phpt

@@ -21,6 +21,13 @@ echo clamp('2025-08-01', '2025-08-15', '2025-09-15'), "\n";
 echo clamp('2025-08-20', '2025-08-15', '2025-09-15'), "\n";
 echo clamp(new \DateTimeImmutable('2025-08-01'), new \DateTimeImmutable('2025-08-15'), new \DateTimeImmutable('2025-09-15'))->format('Y-m-d'), "\n";
 echo clamp(new \DateTimeImmutable('2025-08-20'), new \DateTimeImmutable('2025-08-15'), new \DateTimeImmutable('2025-09-15'))->format('Y-m-d'), "\n";
+var_dump(clamp(null, -1, 1));
+var_dump(clamp(null, 1, 3));
+var_dump(clamp(null, -3, -1));
+var_dump(clamp(-9999, null, 10));
+var_dump(clamp(12, null, 10));
+var_dump(clamp(-9999, 5, null));
+var_dump(clamp(12, 5, null));
 
 try {
     var_dump(clamp(4, NAN, 6));
@@ -56,6 +63,13 @@ string(1) "d"
 2025-08-20
 2025-08-15
 2025-08-20
+int(-1)
+int(1)
+int(-3)
+int(-9999)
+int(10)
+int(5)
+int(12)
 clamp(): Argument #2 ($min) cannot be NAN
 clamp(): Argument #3 ($max) cannot be NAN
 clamp(): Argument #2 ($min) must be smaller than or equal to argument #3 ($max)