Fix invalidating conditional expressions after ArrayDimFetch unset

Author: ondrejmirtes

src/Analyser/MutatingScope.php

@@ -4170,6 +4170,23 @@ public function specifyExpressionType(Expr $expr, Type $type, ?Type $nativeType
 $exprString = sprintf('$%s', $variableName);
 $nativeTypes[$exprString] = $nativeType;
 
+$conditionalExpressions = [];
+foreach ($this->conditionalExpressions as $conditionalExprString => $holders) {
+if ($conditionalExprString === $exprString) {
+continue;
+}
+
+foreach ($holders as $holder) {
+foreach (array_keys($holder->getConditionExpressionTypes()) as $conditionExprString2) {
+if ($conditionExprString2 === $exprString) {
+continue 3;
+}
+}
+}
+
+$conditionalExpressions[$conditionalExprString] = $holders;
+}
+
 return $this->scopeFactory->create(
 $this->context,
 $this->isDeclareStrictTypes(),
@@ -4178,7 +4195,7 @@ public function specifyExpressionType(Expr $expr, Type $type, ?Type $nativeType
 $this->getNamespace(),
 $variableTypes,
 $this->moreSpecificTypes,
-$this->conditionalExpressions,
+$conditionalExpressions,
 $this->inClosureBindScopeClass,
 $this->anonymousFunctionReflection,
 $this->inFirstLevelStatement,

tests/PHPStan/Analyser/NodeScopeResolverTest.php

@@ -912,6 +912,7 @@ public function dataFileAsserts(): iterable
 yield from $this->gatherAssertTypes(__DIR__ . '/data/non-empty-string-str-containing-fns.php');
 yield from $this->gatherAssertTypes(__DIR__ . '/data/bug-6609.php');
 yield from $this->gatherAssertTypes(__DIR__ . '/data/non-empty-string-substr-specifying.php');
+yield from $this->gatherAssertTypes(__DIR__ . '/data/unset-conditional-expressions.php');
 }
 
 /**

tests/PHPStan/Analyser/data/unset-conditional-expressions.php

@@ -0,0 +1,30 @@
+<?php
+
+namespace UnsetConditionalExpressions;
+
+use function PHPStan\Testing\assertType;
+
+class Foo
+{
+
+/**
+ * @param array<string, mixed> $filteredParameters
+ */
+public function doFoo(array $filteredParameters, array $a): void
+{
+$otherFilteredParameters = $filteredParameters;
+foreach ($a as $k => $v) {
+if (rand(0, 1)) {
+unset($otherFilteredParameters[$k]);
+}
+}
+
+if (count($otherFilteredParameters) > 0) {
+return;
+}
+
+assertType('array{}', $otherFilteredParameters);
+assertType('array<string, mixed>', $filteredParameters);
+}
+
+}