Add float mul integer type to NumericReturnTypeFromStrictScalarReturn…

…sRector (#4376)

rules-tests/TypeDeclaration/Rector/ClassMethod/NumericReturnTypeFromStrictScalarReturnsRector/Fixture/mul_float_integer.php.inc

@@ -0,0 +1,27 @@
+<?php
+
+namespace Rector\Tests\TypeDeclaration\Rector\ClassMethod\NumericReturnTypeFromStrictScalarReturnsRector\Fixture;
+
+final class MulFloatInteger
+{
+    public function resolve(int $first, float $second)
+    {
+        return $first * $second;
+    }
+}
+
+?>
+-----
+<?php
+
+namespace Rector\Tests\TypeDeclaration\Rector\ClassMethod\NumericReturnTypeFromStrictScalarReturnsRector\Fixture;
+
+final class MulFloatInteger
+{
+    public function resolve(int $first, float $second): float
+    {
+        return $first * $second;
+    }
+}
+
+?>

rules/TypeDeclaration/Rector/ClassMethod/NumericReturnTypeFromStrictScalarReturnsRector.php

@@ -151,6 +151,18 @@ private function refactorBinaryOp(
             return $functionLike;
         }
 
+        if ($binaryOp instanceof Mul) {
+            if ($leftType instanceof FloatType && $rightType instanceof IntegerType) {
+                $functionLike->returnType = new Identifier('float');
+                return $functionLike;
+            }
+
+            if ($leftType instanceof IntegerType && $rightType instanceof FloatType) {
+                $functionLike->returnType = new Identifier('float');
+                return $functionLike;
+            }
+        }
+
         return null;
     }
 }