Fix while/for loop exit scope for conditions with pre/post increment/decrement

src/Analyser/NodeScopeResolver.php

@@ -1502,9 +1502,10 @@ public function processStmtNode(
 			$bodyScope = $bodyScope->mergeWith($scope);
 			$bodyScopeMaybeRan = $bodyScope;
 			$storage = $originalStorage;
-			$bodyScope = $this->processExprNode($stmt, $stmt->cond, $bodyScope, $storage, $nodeCallback, ExpressionContext::createDeep())->getTruthyScope();
+			$condResult = $this->processExprNode($stmt, $stmt->cond, $bodyScope, $storage, $nodeCallback, ExpressionContext::createDeep());
+			$bodyScope = $condResult->getTruthyScope();
 			$finalScopeResult = $this->processStmtNodesInternal($stmt, $stmt->stmts, $bodyScope, $storage, $nodeCallback, $context)->filterOutLoopExitPoints();
-			$finalScope = $finalScopeResult->getScope()->filterByFalseyValue($stmt->cond);
+			$finalScope = $this->getWhileLoopExitScope($stmt->cond, $condResult, $finalScopeResult->getScope());
 
 			$alwaysIterates = false;
 			$neverIterates = false;
@@ -1727,9 +1728,11 @@ public function processStmtNode(
 			$bodyScope = $bodyScope->mergeWith($initScope);
 
 			$alwaysIterates = TrinaryLogic::createFromBoolean($context->isTopLevel());
+			$lastCondResult = null;
 			if ($lastCondExpr !== null) {
 				$alwaysIterates = $alwaysIterates->and($bodyScope->getType($lastCondExpr)->toBoolean()->isTrue());
-				$bodyScope = $this->processExprNode($stmt, $lastCondExpr, $bodyScope, $storage, $nodeCallback, ExpressionContext::createDeep())->getTruthyScope();
+				$lastCondResult = $this->processExprNode($stmt, $lastCondExpr, $bodyScope, $storage, $nodeCallback, ExpressionContext::createDeep());
+				$bodyScope = $lastCondResult->getTruthyScope();
 				$bodyScope = $this->inferForLoopExpressions($stmt, $lastCondExpr, $bodyScope);
 			}
 
@@ -1746,7 +1749,7 @@ public function processStmtNode(
 			$finalScope = $finalScope->generalizeWith($loopScope);
 
 			if ($lastCondExpr !== null) {
-				$finalScope = $finalScope->filterByFalseyValue($lastCondExpr);
+				$finalScope = $this->getWhileLoopExitScope($lastCondExpr, $lastCondResult, $finalScope);
 			}
 
 			$breakExitPoints = $finalScopeResult->getExitPointsByType(Break_::class);
@@ -4819,6 +4822,31 @@ private function getNextUnreachableStatements(array $nodes, bool $earlyBinding):
 		return $stmts;
 	}
 
+	private function conditionHasDirectIncDec(Expr $cond): bool
+	{
+		if (!$cond instanceof BinaryOp\Smaller && !$cond instanceof BinaryOp\SmallerOrEqual && !$cond instanceof BinaryOp\Greater && !$cond instanceof BinaryOp\GreaterOrEqual) {
+			return false;
+		}
+
+		return $cond->left instanceof Expr\PreInc
+			|| $cond->left instanceof Expr\PreDec
+			|| $cond->left instanceof Expr\PostInc
+			|| $cond->left instanceof Expr\PostDec
+			|| $cond->right instanceof Expr\PreInc
+			|| $cond->right instanceof Expr\PreDec
+			|| $cond->right instanceof Expr\PostInc
+			|| $cond->right instanceof Expr\PostDec;
+	}
+
+	private function getWhileLoopExitScope(Expr $cond, ExpressionResult $condResult, MutatingScope $bodyOutputScope): MutatingScope
+	{
+		if ($this->conditionHasDirectIncDec($cond)) {
+			return $condResult->getFalseyScope();
+		}
+
+		return $bodyOutputScope->filterByFalseyValue($cond);
+	}
+
 	private function inferForLoopExpressions(For_ $stmt, Expr $lastCondExpr, MutatingScope $bodyScope): MutatingScope
 	{
 		// infer $items[$i] type from for ($i = 0; $i < count($items); $i++) {...}

tests/PHPStan/Analyser/nsrt/bug-7230.php

@@ -0,0 +1,82 @@
+<?php
+
+declare(strict_types = 1);
+
+namespace Bug7230;
+
+use function PHPStan\Testing\assertType;
+
+function preIncWhile(): void
+{
+	$counter = 0;
+	while (++$counter < 100) {
+		assertType('int<1, 99>', $counter);
+	}
+	assertType('int<100, max>', $counter);
+
+	if ($counter === 100) {
+		assertType('100', $counter);
+	}
+}
+
+function preIncWhileWithBody(): void
+{
+	$tmp = '';
+	$counter = 0;
+	while (++$counter < 100) {
+		$tmp = 'tmp_' . (string) $counter;
+	}
+	assertType('int<100, max>', $counter);
+
+	if ($counter === 100) {
+		$tmp = 'tmp_hardcoded';
+	}
+
+	assertType("''|(literal-string&lowercase-string&non-falsy-string)", $tmp);
+}
+
+function postIncWhile(): void
+{
+	$counter = 0;
+	while ($counter++ < 100) {
+		assertType('int<1, 100>', $counter);
+	}
+	assertType('int<101, max>', $counter);
+
+	if ($counter === 101) {
+		assertType('101', $counter);
+	}
+}
+
+function preDecWhile(): void
+{
+	$counter = 100;
+	while (--$counter > 0) {
+		assertType('int<1, 99>', $counter);
+	}
+	assertType('int<min, 0>', $counter);
+}
+
+function preIncFor(): void
+{
+	$counter = 0;
+	for (; ++$counter < 5; ) {
+	}
+	assertType('int<5, max>', $counter);
+}
+
+function postIncFor(): void
+{
+	$counter = 0;
+	for (; $counter++ < 5; ) {
+	}
+	assertType('int<6, max>', $counter);
+}
+
+function preDecFor(): void
+{
+	$counter = 10;
+	for (; --$counter > 0; ) {
+	}
+	assertType('int<min, 0>', $counter);
+}