Property is also read for ??= and other assign ops

ondrejmirtes · ondrejmirtes · commit efb11ec5cfae · 2020-08-12T23:02:22.000+02:00
diff --git a/src/Analyser/NodeScopeResolver.php b/src/Analyser/NodeScopeResolver.php
@@ -629,6 +629,10 @@ private function processStmtNode(
 				if (!$node instanceof Expr) {
 					return;
 				}
+				if ($node instanceof Expr\AssignOp) {
+					$customCallback($node->var, $scope);
+					return;
+				}
 				if ($node instanceof Node\Scalar\EncapsedStringPart) {
 					return;
 				}
diff --git a/tests/PHPStan/Rules/DeadCode/UnusedPrivatePropertyRuleTest.php b/tests/PHPStan/Rules/DeadCode/UnusedPrivatePropertyRuleTest.php
@@ -138,4 +138,11 @@ public function testTrait(): void
 		$this->analyse([__DIR__ . '/data/private-property-trait.php'], []);
 	}
 
+	public function testBug3636(): void
+	{
+		$this->alwaysWrittenTags = [];
+		$this->alwaysReadTags = [];
+		$this->analyse([__DIR__ . '/data/bug-3636.php'], []);
+	}
+
 }
diff --git a/tests/PHPStan/Rules/DeadCode/data/bug-3636.php b/tests/PHPStan/Rules/DeadCode/data/bug-3636.php
@@ -0,0 +1,16 @@
+<?php
+
+namespace Bug3636;
+
+class Foo
+{
+
+	/** @var \DateTimeImmutable */
+	private $date;
+
+	public function getDate(): \DateTimeImmutable
+	{
+		return $this->date ??= new \DateTimeImmutable();
+	}
+
+}

Original file line number	Diff line number	Diff line change
`@@ -629,6 +629,10 @@ private function processStmtNode(`
`629`	`629`	`if (!$node instanceof Expr) {`
`630`	`630`	`return;`
`631`	`631`	`}`
	`632`	`+ if ($node instanceof Expr\AssignOp) {`
	`633`	`+ $customCallback($node->var, $scope);`
	`634`	`+ return;`
	`635`	`+ }`
`632`	`636`	`if ($node instanceof Node\Scalar\EncapsedStringPart) {`
`633`	`637`	`return;`
`634`	`638`	`}`
Original file line number	Diff line number	Diff line change
`@@ -138,4 +138,11 @@ public function testTrait(): void`
`138`	`138`	`$this->analyse([__DIR__ . '/data/private-property-trait.php'], []);`
`139`	`139`	`}`
`140`	`140`
	`141`	`+ public function testBug3636(): void`
	`142`	`+ {`
	`143`	`+ $this->alwaysWrittenTags = [];`
	`144`	`+ $this->alwaysReadTags = [];`
	`145`	`+ $this->analyse([__DIR__ . '/data/bug-3636.php'], []);`
	`146`	`+ }`
	`147`	`+`
`141`	`148`	`}`