Add dynamic return type extension for wp_die() (#201)

* Add dynamic return type extension for wp_die()

* Update tests for wp_die()

Co-authored-by: Viktor Szépe <viktor@szepe.net>

---------

Co-authored-by: Viktor Szépe <viktor@szepe.net>

extension.neon

@@ -95,6 +95,10 @@ services:
         class: SzepeViktor\PHPStan\WordPress\WpParseUrlFunctionDynamicReturnTypeExtension
         tags:
             - phpstan.broker.dynamicFunctionReturnTypeExtension
+    -
+        class: SzepeViktor\PHPStan\WordPress\WpDieDynamicFunctionReturnTypeExtension
+        tags:
+            - phpstan.broker.dynamicFunctionReturnTypeExtension
     -
         class: SzepeViktor\PHPStan\WordPress\HookDocsVisitor
         tags:
@@ -124,7 +128,6 @@ parameters:
         - SAVEQUERIES
         - SCRIPT_DEBUG
     earlyTerminatingFunctionCalls:
-        - wp_die
         - wp_send_json
         - wp_send_json_success
         - wp_send_json_error

src/WpDieDynamicFunctionReturnTypeExtension.php

@@ -0,0 +1,53 @@
+<?php
+
+/**
+ * Set return type of wp_die().
+ */
+
+declare(strict_types=1);
+
+namespace SzepeViktor\PHPStan\WordPress;
+
+use PhpParser\Node\Expr\FuncCall;
+use PHPStan\Analyser\Scope;
+use PHPStan\Reflection\FunctionReflection;
+use PHPStan\Type\Constant\ConstantStringType;
+use PHPStan\Type\Type;
+use PHPStan\Type\VoidType;
+use PHPStan\Type\NeverType;
+
+class WpDieDynamicFunctionReturnTypeExtension implements \PHPStan\Type\DynamicFunctionReturnTypeExtension
+{
+    public function isFunctionSupported(FunctionReflection $functionReflection): bool
+    {
+        return $functionReflection->getName() === 'wp_die';
+    }
+
+    // phpcs:ignore SlevomatCodingStandard.Functions.UnusedParameter
+    public function getTypeFromFunctionCall(FunctionReflection $functionReflection, FuncCall $functionCall, Scope $scope): Type
+    {
+        $args = $functionCall->getArgs();
+
+        // Called without $args parameter
+        if (count($args) < 3) {
+            return new NeverType();
+        }
+
+        $argType = $scope->getType($args[2]->value);
+
+        // Return void for non constant arrays.
+        if (! $argType->isConstantArray()->yes()) {
+            return new VoidType();
+        }
+
+        // Return never if the key 'exit' is not set.
+        if (! $argType->hasOffsetValueType(new ConstantStringType('exit'))->yes()) {
+            return new NeverType();
+        }
+
+        // Note WP's wp_die handlers do lazy comparison
+        return $argType->getOffsetValueType(new ConstantStringType('exit'))->toBoolean()->isTrue()->yes()
+            ? new NeverType()
+            : new VoidType();
+    }
+}

tests/DynamicReturnTypeExtensionTest.php

@@ -31,6 +31,7 @@ public function dataFileAsserts(): iterable
         yield from $this->gatherAssertTypes(__DIR__ . '/data/term_exists.php');
         yield from $this->gatherAssertTypes(__DIR__ . '/data/wp_error_parameter.php');
         yield from $this->gatherAssertTypes(__DIR__ . '/data/wp_parse_url.php');
+        yield from $this->gatherAssertTypes(__DIR__ . '/data/wp_die.php');
         yield from $this->gatherAssertTypes(__DIR__ . '/data/wp_theme_get.php');
     }
 

tests/data/wp_die.php

@@ -0,0 +1,15 @@
+<?php
+
+declare(strict_types=1);
+
+namespace SzepeViktor\PHPStan\WordPress\Tests;
+
+use function PHPStan\Testing\assertType;
+
+/** @var array $array */
+$array = null;
+
+assertType('*NEVER*', wp_die('', ''));
+assertType('*NEVER*', wp_die('', '', ['exit' => true]));
+assertType('void', wp_die('', '', ['exit' => false]));
+assertType('void', wp_die('', '', $array));