More precise return type for trigger_error

phpstan-baseline.neon

@@ -1497,11 +1497,6 @@ parameters:
 count: 1
 path: src/Type/Php/StrlenFunctionReturnTypeExtension.php
 
--
-message: "#^Doing instanceof PHPStan\\\\Type\\\\ConstantScalarType is error\\-prone and deprecated\\. Use Type\\:\\:isConstantScalarValue\\(\\) or Type\\:\\:getConstantScalarTypes\\(\\) or Type\\:\\:getConstantScalarValues\\(\\) instead\\.$#"
-count: 1
-path: src/Type/Php/TriggerErrorDynamicReturnTypeExtension.php
-
 -
 message: "#^Doing instanceof PHPStan\\\\Type\\\\ObjectType is error\\-prone and deprecated\\. Use Type\\:\\:isObject\\(\\) or Type\\:\\:getObjectClassNames\\(\\) instead\\.$#"
 count: 2

src/Type/Php/TriggerErrorDynamicReturnTypeExtension.php

@@ -4,34 +4,63 @@
 
 use PhpParser\Node\Expr\FuncCall;
 use PHPStan\Analyser\Scope;
+use PHPStan\Php\PhpVersion;
 use PHPStan\Reflection\FunctionReflection;
 use PHPStan\Reflection\ParametersAcceptorSelector;
-use PHPStan\Type\ConstantScalarType;
+use PHPStan\Type\Constant\ConstantBooleanType;
+use PHPStan\Type\Constant\ConstantIntegerType;
 use PHPStan\Type\DynamicFunctionReturnTypeExtension;
 use PHPStan\Type\NeverType;
 use PHPStan\Type\Type;
 use function count;
+use function in_array;
+use const E_USER_DEPRECATED;
 use const E_USER_ERROR;
+use const E_USER_NOTICE;
+use const E_USER_WARNING;
 
 class TriggerErrorDynamicReturnTypeExtension implements DynamicFunctionReturnTypeExtension
 {
 
+public function __construct(private PhpVersion $phpVersion)
+{
+}
+
 public function isFunctionSupported(FunctionReflection $functionReflection): bool
 {
 return $functionReflection->getName() === 'trigger_error';
 }
 
 public function getTypeFromFunctionCall(FunctionReflection $functionReflection, FuncCall $functionCall, Scope $scope): Type
 {
-if (count($functionCall->getArgs()) < 2) {
+$args = $functionCall->getArgs();
+
+if (count($args) === 0) {
 return ParametersAcceptorSelector::selectSingle($functionReflection->getVariants())->getReturnType();
 }
 
-$errorType = $scope->getType($functionCall->getArgs()[1]->value);
-if ($errorType instanceof ConstantScalarType) {
-if ($errorType->getValue() === E_USER_ERROR) {
+if (count($args) === 1) {
+return new ConstantBooleanType(true);
+}
+
+$errorType = $scope->getType($args[1]->value);
+
+if ($errorType instanceof ConstantIntegerType) {
+$errorLevel = $errorType->getValue();
+
+if ($errorLevel === E_USER_ERROR) {
 return new NeverType(true);
 }
+
+if (!in_array($errorLevel, [E_USER_WARNING, E_USER_NOTICE, E_USER_DEPRECATED], true)) {
+if ($this->phpVersion->throwsValueErrorForInternalFunctions()) {
+return new NeverType(true);
+}
+
+return new ConstantBooleanType(false);
+}
+
+return new ConstantBooleanType(true);
 }
 
 return ParametersAcceptorSelector::selectSingle($functionReflection->getVariants())->getReturnType();

tests/PHPStan/Analyser/NodeScopeResolverTest.php

@@ -1309,6 +1309,12 @@ public function dataFileAsserts(): iterable
 yield from $this->gatherAssertTypes(__DIR__ . '/data/gettype.php');
 yield from $this->gatherAssertTypes(__DIR__ . '/data/array_splice.php');
 yield from $this->gatherAssertTypes(__DIR__ . '/../Rules/Methods/data/bug-9542.php');
+
+if (PHP_VERSION_ID >= 80000) {
+yield from $this->gatherAssertTypes(__DIR__ . '/data/trigger-error-php8.php');
+} else {
+yield from $this->gatherAssertTypes(__DIR__ . '/data/trigger-error-php7.php');
+}
 }
 
 /**

tests/PHPStan/Analyser/data/bug-5992.php

@@ -9,7 +9,7 @@ function StringValue(): string
 $values = [1, 'one', true, null, []];
 $value = $values[rand(0, 4)];
 if (!is_string($value)) {
-assertType('bool', trigger_error("just a soft warning", E_USER_WARNING));
+assertType('true', trigger_error("just a soft warning", E_USER_WARNING));
 assertType('*NEVER*', trigger_error("error which halts the script", E_USER_ERROR));
 }
 return $value;

tests/PHPStan/Analyser/data/trigger-error-php7.php

@@ -0,0 +1,15 @@
+<?php declare(strict_types = 1);
+
+namespace TriggerErrorPhp7;
+
+use function PHPStan\Testing\assertType;
+
+$errorLevels = [E_USER_DEPRECATED, E_USER_ERROR, E_USER_NOTICE, E_USER_WARNING, E_NOTICE, E_WARNING];
+
+assertType('true', trigger_error('bar'));
+assertType('true', trigger_error('bar', $errorLevels[0]));
+assertType('*NEVER*', trigger_error('bar', $errorLevels[1]));
+assertType('true', trigger_error('bar', $errorLevels[2]));
+assertType('true', trigger_error('bar', $errorLevels[3]));
+assertType('false', trigger_error('bar', $errorLevels[4]));
+assertType('false', trigger_error('bar', $errorLevels[5]));

tests/PHPStan/Analyser/data/trigger-error-php8.php

@@ -0,0 +1,15 @@
+<?php declare(strict_types = 1);
+
+namespace TriggerErrorPhp8;
+
+use function PHPStan\Testing\assertType;
+
+$errorLevels = [E_USER_DEPRECATED, E_USER_ERROR, E_USER_NOTICE, E_USER_WARNING, E_NOTICE, E_WARNING];
+
+assertType('true', trigger_error('bar'));
+assertType('true', trigger_error('bar', $errorLevels[0]));
+assertType('*NEVER*', trigger_error('bar', $errorLevels[1]));
+assertType('true', trigger_error('bar', $errorLevels[2]));
+assertType('true', trigger_error('bar', $errorLevels[3]));
+assertType('*NEVER*', trigger_error('bar', $errorLevels[4]));
+assertType('*NEVER*', trigger_error('bar', $errorLevels[5]));