support unary-minus on IntegerRangeType

Author: staabm

src/Analyser/MutatingScope.php

@@ -1006,6 +1006,7 @@ private function resolveType(Expr $node): Type
 		if ($node instanceof Node\Expr\UnaryMinus) {
 			$type = $this->getType($node->expr)->toNumber();
 			$scalarValues = TypeUtils::getConstantScalars($type);
+
 			if (count($scalarValues) > 0) {
 				$newTypes = [];
 				foreach ($scalarValues as $scalarValue) {
@@ -1019,6 +1020,15 @@ private function resolveType(Expr $node): Type
 				return TypeCombinator::union(...$newTypes);
 			}
 
+			if ($type instanceof IntegerRangeType) {
+				$negativeRange = $this->resolveType(new Node\Expr\BinaryOp\Mul($node->expr, new LNumber(-1)));
+
+				if ( $negativeRange instanceof IntegerRangeType && ($negativeRange->getMin() === null || $negativeRange->getMax() === null)) {
+					return IntegerRangeType::fromInterval($negativeRange->getMax(), $negativeRange->getMin());
+				}
+				return $negativeRange;
+			}
+
 			return $type;
 		}
 

tests/PHPStan/Analyser/data/integer-range-types.php

@@ -278,4 +278,21 @@ public function math($i, $j, $z, $pi, $r1, $r2, $rMin, $rMax, $x, $y) {
 
 		assertType('5|10|15|20|30', $x / $y);
 	}
+
+	/**
+	 * @param int<1, 10> $r1
+	 * @param int<-5, 10> $r2
+	 * @param int<min, 5> $rMin
+	 * @param int<5, max> $rMax
+	 * @param int<0, 50> $rZero
+	 */
+	public function unaryMinus($r1, $r2, $rMin, $rMax, $rZero) {
+
+		assertType('int<-10, -1>', -$r1);
+		assertType('int<-10, 5>', -$r2);
+		assertType('int<-5, max>', -$rMin);
+		assertType('int<min, -5>', -$rMax);
+		assertType('int<-50, 0>', -$rZero);
+	}
+
 }