- Fixed unwanted narrowing of template variable types

Author: MartinMystikJonas

CHANGELOG.md

@@ -4,6 +4,8 @@
 ### Added
 - Check if value outputted in template (or escaped for output) can be converted to string
 - Support for PHP 8.4
+### Fixed
+- Fixed unwanted narrowing of template variable types
 
 ## [0.18] - 2025-07-22
 ### Updated

src/Resolver/ValueResolver/ValueResolver.php

@@ -21,6 +21,7 @@
 use PHPStan\Analyser\Scope;
 use PHPStan\Type\UnionType;
 use ReflectionMethod;
+use function count;
 use function is_callable;
 use function method_exists;
 
@@ -38,7 +39,8 @@ public function resolve(Expr $expr, Scope $scope, $fallbackEvaluator = null)
             $type = $scope->getType($expr);
 
             $constantScalarValues = $type->getConstantScalarValues();
-            if ($constantScalarValues !== []) {
+
+            if (count($constantScalarValues) === 1) {
                 return $constantScalarValues[0];
             }
 
@@ -158,7 +160,7 @@ public function resolve(Expr $expr, Scope $scope, $fallbackEvaluator = null)
             $options = [];
             foreach ($type->getTypes() as $subType) {
                 $constantScalarValues = $subType->getConstantScalarValues();
-                if ($constantScalarValues === []) {
+                if (count($constantScalarValues) !== 1) {
                     return null;
                 }
                 $options[] = $constantScalarValues[0];

tests/Rule/LatteTemplatesRule/SimpleControl/Fixtures/Variables/SomeControl.php

@@ -9,6 +9,8 @@
 
 final class SomeControl extends Control
 {
+    public bool $property;
+
     public function render(): void
     {
         $this->template->a = 'a';
@@ -26,6 +28,7 @@ public function render(): void
         [$this->template->{$dynamic1}, $this->template->{$dynamic2}] = [$dynamic1, $dynamic2];
 
         $this->template->object = new stdClass();
+        $this->template->boolProperty = $this->property;
 
         $this->template->render(__DIR__ . '/default.latte');
     }

tests/Rule/LatteTemplatesRule/SimpleControl/Fixtures/Variables/default.latte

@@ -14,3 +14,5 @@
 {php \PHPStan\dumpType($someVariableWithDefault)}
 
 {$object}
+
+{php \PHPStan\dumpType($boolProperty)}

tests/Rule/LatteTemplatesRule/SimpleControl/LatteTemplatesRuleForSimpleControlTest.php

@@ -414,6 +414,11 @@ public function testVariables(): void
                 16,
                 'default.latte',
             ],
+            [
+                'Dumped type: bool',
+                18,
+                'default.latte',
+            ],
         ]);
     }