Fix variable certainty after exhaustive switch

phpstan · Jul 28, 2022 · e36e22c · e36e22c
1 parent 6478c73
commit e36e22c
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Showing 3 changed files with 34 additions and 2 deletions.
diff --git a/src/Analyser/NodeScopeResolver.php b/src/Analyser/NodeScopeResolver.php
@@ -1160,7 +1160,9 @@ private function processStmtNode(
 				}
 			}
 
-			if (!$hasDefaultCase) {
+			$exhaustive = $scopeForBranches->getType($stmt->cond) instanceof NeverType;
+
+			if (!$hasDefaultCase && !$exhaustive) {
 				$alwaysTerminating = false;
 			}
 
@@ -1169,7 +1171,7 @@ private function processStmtNode(
 				$alwaysTerminating = $alwaysTerminating && $branchFinalScopeResult->isAlwaysTerminating();
 			}
 
-			if (!$hasDefaultCase || $finalScope === null) {
+			if ((!$hasDefaultCase && !$exhaustive) || $finalScope === null) {
 				$finalScope = $scope->mergeWith($finalScope);
 			}
 

diff --git a/tests/PHPStan/Rules/Variables/DefinedVariableRuleTest.php b/tests/PHPStan/Rules/Variables/DefinedVariableRuleTest.php
@@ -854,4 +854,13 @@ public function testBug3601(): void
 		$this->analyse([__DIR__ . '/data/bug-3601.php'], []);
 	}
 
+	public function testBug1016(): void
+	{
+		$this->cliArgumentsVariablesRegistered = true;
+		$this->polluteScopeWithLoopInitialAssignments = true;
+		$this->checkMaybeUndefinedVariables = true;
+		$this->polluteScopeWithAlwaysIterableForeach = true;
+		$this->analyse([__DIR__ . '/data/bug-1016.php'], []);
+	}
+
 }
diff --git a/tests/PHPStan/Rules/Variables/data/bug-1016.php b/tests/PHPStan/Rules/Variables/data/bug-1016.php
@@ -0,0 +1,21 @@
+<?php declare(strict_types=1);
+
+namespace Bug1016;
+
+function () {
+	foreach ([1, 2, 3] as $i) {
+		switch ($i) {
+			case 1:
+				$a = "hello";
+				break;
+			case 2:
+				$a = "goodbye";
+				break;
+			case 3:
+				$a = "hello again";
+				break;
+		}
+
+		echo $a;
+	}
+};