handle invalid name given to constant()

Author: staabm

src/Type/Php/ConstantFunctionReturnTypeExtension.php

@@ -6,6 +6,7 @@
 use PHPStan\Analyser\Scope;
 use PHPStan\Reflection\FunctionReflection;
 use PHPStan\Type\DynamicFunctionReturnTypeExtension;
+use PHPStan\Type\ErrorType;
 use PHPStan\Type\Type;
 use PHPStan\Type\TypeCombinator;
 use function count;
@@ -39,7 +40,13 @@ public function getTypeFromFunctionCall(
 			if ($constantName->getValue() === '') {
 				return null;
 			}
-			$results[] = $scope->getType($this->constantHelper->createExprFromConstantName($constantName->getValue()));
+
+			$expr = $this->constantHelper->createExprFromConstantName($constantName->getValue());
+			if ($expr === null) {
+				return new ErrorType();
+			}
+
+			$results[] = $scope->getType($expr);
 		}
 
 		if (count($results) > 0) {

src/Type/Php/ConstantHelper.php

@@ -8,7 +8,6 @@
 use PhpParser\Node\Identifier;
 use PhpParser\Node\Name;
 use PhpParser\Node\Name\FullyQualified;
-use PHPStan\ShouldNotHappenException;
 use function count;
 use function explode;
 use function ltrim;
@@ -19,13 +18,13 @@ class ConstantHelper
 	/**
 	 * @param non-empty-string $constantName
 	 */
-	public function createExprFromConstantName(string $constantName): Expr
+	public function createExprFromConstantName(string $constantName): ?Expr
 	{
 		$classConstParts = explode('::', $constantName);
 		if (count($classConstParts) >= 2) {
 			$fqcn = ltrim($classConstParts[0], '\\');
 			if ($fqcn === '') {
-				throw new ShouldNotHappenException();
+				return null;
 			}
 
 			$classConstName = new FullyQualified($fqcn);

src/Type/Php/DefinedConstantTypeSpecifyingExtension.php

@@ -54,8 +54,13 @@ public function specifyTypes(
 			return new SpecifiedTypes([], []);
 		}
 
+		$expr = $this->constantHelper->createExprFromConstantName($constantName->getValue());
+		if ($expr === null) {
+			return new SpecifiedTypes([], []);
+		}
+
 		return $this->typeSpecifier->create(
-			$this->constantHelper->createExprFromConstantName($constantName->getValue()),
+			$expr,
 			new MixedType(),
 			$context,
 			false,

tests/PHPStan/Analyser/data/constant.php

@@ -38,3 +38,4 @@ function doFoo(string $constantName): void
 assertType('Constant\Suit::Hearts', constant('\Constant\Suit::Hearts'));
 
 assertType('*ERROR*', constant('UNDEFINED'));
+assertType('*ERROR*', constant('::aa'));