address feedback

Author: mvorisek

src/Type/Php/DateFunctionReturnTypeHelper.php

@@ -76,8 +76,12 @@ public function buildReturnTypeFromFormat(string $formatString, bool $useMicrose
 				return $this->buildNumericRangeType(0, 1, false);
 			case 'u':
 				return $useMicrosec
-					? new IntersectionType([new StringType(), new AccessoryNumericStringType()])
+					? new IntersectionType([new StringType(), new AccessoryNonFalsyStringType(), new AccessoryNumericStringType()])
 					: new ConstantStringType('000000');
+			case 'v':
+				return $useMicrosec
+					? new IntersectionType([new StringType(), new AccessoryNonFalsyStringType(), new AccessoryNumericStringType()])
+					: new ConstantStringType('000');
 		}
 
 		$date = date($formatString);

tests/PHPStan/Analyser/nsrt/bug-6613.php

@@ -8,4 +8,8 @@ function (\DateTime $dt) {
 	assertType("'000000'", date('u'));
 	assertType('numeric-string', date_format($dt, 'u'));
 	assertType('numeric-string', $dt->format('u'));
+
+	assertType("'000'", date('v'));
+	assertType('numeric-string', date_format($dt, 'v'));
+	assertType('numeric-string', $dt->format('v'));
 };