Avoid false-positive Offset does not exist on via isset

VincentLanglet · ondrejmirtes · commit 2066a7ee3bcc · 2021-02-16T12:29:34.000+01:00
diff --git a/src/Rules/Arrays/NonexistentOffsetInArrayDimFetchCheck.php b/src/Rules/Arrays/NonexistentOffsetInArrayDimFetchCheck.php
@@ -85,7 +85,7 @@ static function (Type $type) use ($dimType): bool {
 			}
 		}
 
-		if ($report) {
+		if (!$scope->isInExpressionAssign($var) && $report) {
 			return [
 				RuleErrorBuilder::message(sprintf('Offset %s does not exist on %s.', $dimType->describe(VerbosityLevel::value()), $type->describe(VerbosityLevel::value())))->build(),
 			];
diff --git a/tests/PHPStan/Rules/Arrays/data/nonexistent-offset.php b/tests/PHPStan/Rules/Arrays/data/nonexistent-offset.php
@@ -444,3 +444,18 @@ public function doFoo(): void
 	}
 
 }
+
+class Bug3282
+{
+	/**
+	 * @phpstan-param array{event: string, msg?: array{ts?: int}} $array
+	 */
+	public function foo(array $array): int
+	{
+		if (isset($array['msg']['ts'])) {
+			return 1;
+		}
+
+		return 0;
+	}
+}

Original file line number	Diff line number	Diff line change
`@@ -85,7 +85,7 @@ static function (Type $type) use ($dimType): bool {`
`85`	`85`	`}`
`86`	`86`	`}`
`87`	`87`
`88`		`- if ($report) {`
	`88`	`+ if (!$scope->isInExpressionAssign($var) && $report) {`
`89`	`89`	`return [`
`90`	`90`	`RuleErrorBuilder::message(sprintf('Offset %s does not exist on %s.', $dimType->describe(VerbosityLevel::value()), $type->describe(VerbosityLevel::value())))->build(),`
`91`	`91`	`];`