Specify conditional types for all falsey scalars

phpstan-baseline.neon

@@ -411,12 +411,6 @@ parameters:
 			count: 1
 			path: src/Reflection/ClassReflection.php
 
-		-
-			rawMessage: 'Method PHPStan\Reflection\ClassReflection::getCacheKey() should return string but returns string|null.'
-			identifier: return.type
-			count: 1
-			path: src/Reflection/ClassReflection.php
-
 		-
 			rawMessage: Binary operation "&" between bool|float|int|string|null and bool|float|int|string|null results in an error.
 			identifier: binaryOp.invalid

src/Analyser/NodeScopeResolver.php

@@ -173,6 +173,7 @@
 use PHPStan\Type\Constant\ConstantArrayTypeBuilder;
 use PHPStan\Type\Constant\ConstantIntegerType;
 use PHPStan\Type\Constant\ConstantStringType;
+use PHPStan\Type\ConstantTypeHelper;
 use PHPStan\Type\FileTypeMapper;
 use PHPStan\Type\GeneralizePrecision;
 use PHPStan\Type\Generic\TemplateTypeHelper;
@@ -6108,6 +6109,41 @@ private function processAssignVar(
 					$conditionalExpressions = $this->processSureNotTypesForConditionalExpressionsAfterAssign($scope, $var->name, $conditionalExpressions, $falseySpecifiedTypes, $falseyType);
 				}
 
+				foreach ([null, false, 0, 0.0, '', '0', []] as $falseyScalar) {
+					$falseyType = ConstantTypeHelper::getTypeFromValue($falseyScalar);
+					$withoutFalseyType = TypeCombinator::remove($type, $falseyType);
+					if (
+						$withoutFalseyType->equals($type)
+						|| $withoutFalseyType->equals($truthyType)
+					) {
+						continue;
+					}
+
+					if ($falseyScalar === null) {
+						$astNode = new ConstFetch(new Name('null'));
+					} elseif ($falseyScalar === false) {
+						$astNode = new ConstFetch(new Name('false'));
+					} elseif ($falseyScalar === 0) {
+						$astNode = new Node\Scalar\Int_($falseyScalar);
+					} elseif ($falseyScalar === 0.0) {
+						$astNode = new Node\Scalar\Float_($falseyScalar);
+					} elseif (in_array($falseyScalar, ['', '0'], true)) {
+						$astNode = new Node\Scalar\String_($falseyScalar);
+					} elseif ($falseyScalar === []) {
+						$astNode = new Node\Expr\Array_($falseyScalar);
+					}
+
+					$notIdenticalConditionExpr = new Expr\BinaryOp\NotIdentical($assignedExpr, $astNode);
+					$notIdenticalSpecifiedTypes = $this->typeSpecifier->specifyTypesInCondition($scope, $notIdenticalConditionExpr, TypeSpecifierContext::createTrue());
+					$conditionalExpressions = $this->processSureTypesForConditionalExpressionsAfterAssign($scope, $var->name, $conditionalExpressions, $notIdenticalSpecifiedTypes, $withoutFalseyType);
+					$conditionalExpressions = $this->processSureNotTypesForConditionalExpressionsAfterAssign($scope, $var->name, $conditionalExpressions, $notIdenticalSpecifiedTypes, $withoutFalseyType);
+
+					$identicalConditionExpr = new Expr\BinaryOp\Identical($assignedExpr, $astNode);
+					$identicalSpecifiedTypes = $this->typeSpecifier->specifyTypesInCondition($scope, $identicalConditionExpr, TypeSpecifierContext::createTrue());
+					$conditionalExpressions = $this->processSureTypesForConditionalExpressionsAfterAssign($scope, $var->name, $conditionalExpressions, $identicalSpecifiedTypes, $falseyType);
+					$conditionalExpressions = $this->processSureNotTypesForConditionalExpressionsAfterAssign($scope, $var->name, $conditionalExpressions, $identicalSpecifiedTypes, $falseyType);
+				}
+
 				$this->callNodeCallback($nodeCallback, new VariableAssignNode($var, $assignedExpr), $scopeBeforeAssignEval, $storage);
 				$scope = $scope->assignVariable($var->name, $type, $scope->getNativeType($assignedExpr), TrinaryLogic::createYes());
 				foreach ($conditionalExpressions as $exprString => $holders) {

tests/PHPStan/Analyser/nsrt/bug-10482.php

@@ -0,0 +1,24 @@
+<?php
+
+namespace Bug10482;
+
+use function PHPStan\Testing\assertType;
+
+class Test
+{
+	public ?int $id;
+}
+
+$test = new Test();
+if (rand(0, 1)) {
+	$test = null;
+}
+
+$testId = $test?->id;
+if (null !== $testId) {
+	assertType('Bug10482\Test', $test);
+}
+
+if ($testId) {
+	assertType('Bug10482\Test', $test);
+}

tests/PHPStan/Analyser/nsrt/bug-13546.php

@@ -66,10 +66,10 @@ function mixedLast($mixed): void
 function firstInCondition(array $array)
 {
 	if (($key = array_key_first($array)) !== null) {
-		assertType('list<string>', $array); // could be 'non-empty-list<string>'
+		assertType('non-empty-list<string>', $array);
 		return $array[$key];
 	}
-	assertType('list<string>', $array);
+	assertType('array{}', $array);
 	return null;
 }
 

tests/PHPStan/Analyser/nsrt/bug-13709.php

@@ -0,0 +1,17 @@
+<?php
+
+namespace Bug13709;
+
+use function PHPStan\Testing\assertType;
+
+function doFOo(string $shortName): void
+{
+	$pos = strpos($shortName, '\\');
+	if ($pos === false) {
+		return;
+	}
+
+	assertType('non-falsy-string', $shortName);
+}
+
+

tests/PHPStan/Analyser/nsrt/bug-14081.php

@@ -48,7 +48,7 @@ function firstNotNull(array $array): mixed
 {
 	if (($key = array_key_first($array)) !== null) {
 		assertType('int<0, max>', $key);
-		assertType('list<string>', $array); // could be non-empty-list<string>
+		assertType('non-empty-list<string>', $array);
 		assertType('string', $array[$key]);
 		return $array[$key];
 	}
@@ -60,7 +60,7 @@ function lastNotNull(array $array): mixed
 {
 	if (($key = array_key_last($array)) !== null) {
 		assertType('int<0, max>', $key);
-		assertType('list<string>', $array); // could be non-empty-list<string>
+		assertType('non-empty-list<string>', $array);
 		assertType('string', $array[$key]);
 		return $array[$key];
 	}

tests/PHPStan/Rules/Arrays/NonexistentOffsetInArrayDimFetchRuleTest.php

@@ -840,7 +840,7 @@ public function testArrayDimFetchAfterArraySearch(): void
 
 		$this->analyse([__DIR__ . '/data/array-dim-after-array-search.php'], [
 			[
-				'Offset int|string might not exist on array.',
+				'Offset int|string might not exist on non-empty-array.',
 				20,
 			],
 		]);

tests/PHPStan/Rules/Methods/CallMethodsRuleTest.php

@@ -3891,4 +3891,13 @@ public function testBug9820(): void
 		]);
 	}
 
+	#[RequiresPhp('>= 8.1')]
+	public function testBug6120(): void
+	{
+		$this->checkThisOnly = false;
+		$this->checkNullables = true;
+		$this->checkUnionTypes = true;
+		$this->analyse([__DIR__ . '/data/bug-6120.php'], []);
+	}
+
 }

tests/PHPStan/Rules/Methods/data/bug-6120.php

@@ -0,0 +1,20 @@
+<?php // lint >= 8.0
+
+declare(strict_types=1);
+
+namespace Bug6120;
+
+class Clazz
+{
+
+	public int $foo = 0;
+
+	public function bar(?Clazz $clazz): void
+	{
+		$result = $clazz?->foo;
+		if ($result !== null) {
+			$clazz->bar(null);
+		}
+	}
+
+}