Remember narrowed types from the constructor when analysing other methods

Author: staabm

src/Analyser/MutatingScope.php

@@ -294,6 +294,54 @@ public function enterDeclareStrictTypes(): self
 		);
 	}
 
+	public function rememberConstructorScope(): self
+	{
+		$expressionTypes = [];
+		foreach ($this->expressionTypes as $exprString => $expressionTypeHolder) {
+			$expr = $expressionTypeHolder->getExpr();
+			if (!$expr instanceof ConstFetch) {
+				continue;
+			}
+			$expressionTypes[$exprString] = $expressionTypeHolder;
+		}
+
+		$nativeExpressionTypes = [];
+		foreach ($this->nativeExpressionTypes as $exprString => $expressionTypeHolder) {
+			$expr = $expressionTypeHolder->getExpr();
+			if (!$expr instanceof ConstFetch) {
+				continue;
+			}
+
+			$nativeExpressionTypes[$exprString] = $expressionTypeHolder;
+		}
+
+		if (array_key_exists('$this', $this->expressionTypes)) {
+			$expressionTypes['$this'] = $this->expressionTypes['$this'];
+		}
+		if (array_key_exists('$this', $this->nativeExpressionTypes)) {
+			$nativeExpressionTypes['$this'] = $this->nativeExpressionTypes['$this'];
+		}
+
+		return $this->scopeFactory->create(
+			$this->context,
+			$this->isDeclareStrictTypes(),
+			$this->getFunction(),
+			$this->getNamespace(),
+			$expressionTypes,
+			$nativeExpressionTypes,
+			$this->conditionalExpressions,
+			$this->inClosureBindScopeClasses,
+			$this->anonymousFunctionReflection,
+			$this->inFirstLevelStatement,
+			[],
+			[],
+			$this->inFunctionCallsStack,
+			$this->afterExtractCall,
+			$this->parentScope,
+			$this->nativeTypesPromoted,
+		);
+	}
+
 	/** @api */
 	public function isInClass(): bool
 	{

src/Analyser/NodeScopeResolver.php

@@ -218,6 +218,7 @@
 use function str_starts_with;
 use function strtolower;
 use function trim;
+use function usort;
 use const PHP_VERSION_ID;
 use const SORT_NUMERIC;
 
@@ -791,6 +792,10 @@ private function processStmtNode(
 					$classReflection,
 					$methodReflection,
 				), $methodScope);
+
+				if ($isConstructor) {
+					$scope = $statementResult->getScope()->rememberConstructorScope();
+				}
 			}
 		} elseif ($stmt instanceof Echo_) {
 			$hasYield = false;
@@ -925,7 +930,17 @@ private function processStmtNode(
 			$classStatementsGatherer = new ClassStatementsGatherer($classReflection, $nodeCallback);
 			$this->processAttributeGroups($stmt, $stmt->attrGroups, $classScope, $classStatementsGatherer);
 
-			$this->processStmtNodes($stmt, $stmt->stmts, $classScope, $classStatementsGatherer, $context);
+			// analyze static methods first, constructor next and instance methods last so we can carry over the scope
+			$classLikeStatements = $stmt->stmts;
+			usort($classLikeStatements, static function ($a, $b) {
+				if (!$a instanceof Node\Stmt\ClassMethod || !$b instanceof Node\Stmt\ClassMethod) {
+					return 0;
+				}
+
+				return [!$a->isStatic(), $a->name->toLowerString() !== '__construct'] <=> [!$b->isStatic(), $b->name->toLowerString() !== '__construct'];
+			});
+
+			$this->processStmtNodes($stmt, $classLikeStatements, $classScope, $classStatementsGatherer, $context);
 			$nodeCallback(new ClassPropertiesNode($stmt, $this->readWritePropertiesExtensionProvider, $classStatementsGatherer->getProperties(), $classStatementsGatherer->getPropertyUsages(), $classStatementsGatherer->getMethodCalls(), $classStatementsGatherer->getReturnStatementsNodes(), $classStatementsGatherer->getPropertyAssigns(), $classReflection), $classScope);
 			$nodeCallback(new ClassMethodsNode($stmt, $classStatementsGatherer->getMethods(), $classStatementsGatherer->getMethodCalls(), $classReflection), $classScope);
 			$nodeCallback(new ClassConstantsNode($stmt, $classStatementsGatherer->getConstants(), $classStatementsGatherer->getConstantFetches(), $classReflection), $classScope);

tests/PHPStan/Rules/Constants/ConstantRuleTest.php

@@ -80,4 +80,20 @@ public function testDefinedScopeMerge(): void
 		]);
 	}
 
+	public function testRememberedConstructorScope(): void
+	{
+		$this->analyse([__DIR__ . '/data/remembered-constructor-scope.php'], [
+			[
+				'Constant REMEMBERED_FOO not found.',
+				23,
+				'Learn more at https://phpstan.org/user-guide/discovering-symbols',
+			],
+			[
+				'Constant REMEMBERED_FOO not found.',
+				38,
+				'Learn more at https://phpstan.org/user-guide/discovering-symbols',
+			],
+		]);
+	}
+
 }

tests/PHPStan/Rules/Constants/data/remembered-constructor-scope.php

@@ -0,0 +1,45 @@
+<?php declare(strict_types=1);
+
+namespace RememberedConstructorScope;
+
+use LogicException;
+
+class HelloWorld
+{
+	public function dooFoo(): void
+	{
+		if (REMEMBERED_FOO === '3') {
+
+		}
+	}
+
+	public function returnFoo(): string
+	{
+		return REMEMBERED_FOO;
+	}
+
+	static public function staticFoo(): void
+	{
+		echo REMEMBERED_FOO; // should error, as can be invoked without instantiation
+	}
+
+	public function __construct()
+	{
+		if (!defined('REMEMBERED_FOO')) {
+			throw new LogicException();
+		}
+		if (!is_string(REMEMBERED_FOO)) {
+			throw new LogicException();
+		}
+	}
+
+	static public function staticFoo2(): void
+	{
+		echo REMEMBERED_FOO; // should error, as can be invoked without instantiation
+	}
+
+	public function returnFoo2(): string
+	{
+		return REMEMBERED_FOO;
+	}
+}