fix prop fetch

Author: staabm

src/Analyser/ExprHandler/Helper/NonNullabilityHelper.php

@@ -30,7 +30,12 @@ public function ensureShallowNonNullability(MutatingScope $scope, Scope $origina
 		}
 
 		// keep certainty
-		$certainty = $originalScope->hasExpressionType($exprToSpecify);
+		$certainty = TrinaryLogic::createYes();
+		$hasExpressionType = $originalScope->hasExpressionType($exprToSpecify);
+		if (!$hasExpressionType->no() || $exprToSpecify instanceof ArrayDimFetch) {
+			$certainty = $hasExpressionType;
+		}
+
 		$exprTypeWithoutNull = TypeCombinator::removeNull($exprType);
 		if ($exprType->equals($exprTypeWithoutNull)) {
 			$originalExprType = $originalScope->getType($exprToSpecify);

tests/PHPStan/Rules/Comparison/BooleanOrConstantConditionRuleTest.php

@@ -375,7 +375,12 @@ public function testBug10305(): void
 	{
 		$this->treatPhpDocTypesAsCertain = true;
 
-		$this->analyse([__DIR__ . '/data/bug-10305.php'], []);
+		$this->analyse([__DIR__ . '/data/bug-10305.php'], [
+			[
+				"Result of || is always true.",
+				10
+			]
+		]);
 	}
 
 }