fix: keep the declared test() type when no test case class is bound

src/Type/Pest/PestTestCaseType.php

@@ -25,17 +25,7 @@ public function resolve(string $filePath): Type
     public function resolveIfBound(string $filePath): ?Type
     {
         // @note: returns null when no binding covers the file, so callers can tell an unbound file from one bound to PHPUnit's TestCase.
-        [$classNames, $traitNames] = $this->partition(
-            $this->pestConfigReader->resolveFileBindings($filePath),
-        );
-
-        if ($classNames === []) {
-            [$classNames, $directoryTraitNames] = $this->partition(
-                $this->pestConfigReader->resolveBindings($filePath),
-            );
-
-            $traitNames = array_values(array_unique([...$directoryTraitNames, ...$traitNames]));
-        }
+        [$classNames, $traitNames] = $this->resolveFileClassAndTraitNames($filePath);
 
         if ($classNames === [] && $traitNames === []) {
             return null;
@@ -45,17 +35,19 @@ public function resolveIfBound(string $filePath): ?Type
             $classNames[] = TestCase::class;
         }
 
-        $classType = $this->toObjectType($classNames);
+        return $this->toTestCaseType($classNames, $traitNames);
+    }
 
-        if ($traitNames === []) {
-            return $classType;
+    public function resolveIfClassBound(string $filePath): ?Type
+    {
+        // @note: returns null unless a binding covers the file with a test case class, as traits bound without in() also cover files that are not tests.
+        [$classNames, $traitNames] = $this->resolveFileClassAndTraitNames($filePath);
+
+        if ($classNames === []) {
+            return null;
         }
 
-        return new PestTestCaseWithTraitsType(
-            $classNames[0],
-            $traitNames,
-            $this->reflectionProvider,
-        );
+        return $this->toTestCaseType($classNames, $traitNames);
     }
 
     /**
@@ -70,6 +62,35 @@ public function resolveFromBindings(array $bindings): ?Type
             return null;
         }
 
+        return $this->toTestCaseType($classNames, $traitNames);
+    }
+
+    /**
+     * @return array{list<class-string>, list<class-string>}
+     */
+    private function resolveFileClassAndTraitNames(string $filePath): array
+    {
+        [$classNames, $traitNames] = $this->partition(
+            $this->pestConfigReader->resolveFileBindings($filePath),
+        );
+
+        if ($classNames === []) {
+            [$classNames, $directoryTraitNames] = $this->partition(
+                $this->pestConfigReader->resolveBindings($filePath),
+            );
+
+            $traitNames = array_values(array_unique([...$directoryTraitNames, ...$traitNames]));
+        }
+
+        return [$classNames, $traitNames];
+    }
+
+    /**
+     * @param  non-empty-list<class-string>  $classNames
+     * @param  list<class-string>  $traitNames
+     */
+    private function toTestCaseType(array $classNames, array $traitNames): Type
+    {
         if ($traitNames === []) {
             return $this->toObjectType($classNames);
         }

src/Type/Pest/TestFunctionProxyMethodExtension.php

@@ -40,7 +40,7 @@ private function isTodoCall(Node $node, Scope $scope): bool
             && $node->name instanceof Identifier
             && $node->name->toLowerString() === 'todo'
             && $this->testFunction->isBareCall($node->var, $scope)
-            && $this->testCaseType->resolveIfBound($scope->getFile()) instanceof Type
+            && $this->testCaseType->resolveIfClassBound($scope->getFile()) instanceof Type
             && ! $scope->getType($node->var)->hasMethod('todo')->yes()
             && $this->testFunction->supportsTodoHelper($scope);
     }

src/Type/Pest/TestFunctionReturnTypeExtension.php

@@ -33,7 +33,7 @@ public function getTypeFromFunctionCall(
             return null;
         }
 
-        $boundType = $this->pestTestCaseType->resolveIfBound($scope->getFile());
+        $boundType = $this->pestTestCaseType->resolveIfClassBound($scope->getFile());
 
         if (! $boundType instanceof Type) {
             return null;

tests/Fixtures/GlobalTraitBinding/modules/Billing/tests/Feature/billing-test-function.php

@@ -0,0 +1,15 @@
+<?php
+
+declare(strict_types=1);
+
+namespace GlobalTraitBindingFeature;
+
+use Tests\Type\Fixtures\CustomTestCase;
+
+use function PHPStan\Testing\assertType;
+
+function helperInsideATestCaseBinding(): void
+{
+    assertType(CustomTestCase::class, test());
+    assertType('string', test()->helperMethod());
+}

tests/Fixtures/GlobalTraitBinding/modules/Billing/tests/Helpers.php

@@ -0,0 +1,12 @@
+<?php
+
+declare(strict_types=1);
+
+namespace GlobalTraitBindingHelpers;
+
+use function PHPStan\Testing\assertType;
+
+function helperOutsideAnyTestCaseBinding(): void
+{
+    assertType('Pest\PendingCalls\TestCall|Pest\Support\HigherOrderTapProxy', test());
+}

tests/Fixtures/GlobalTraitBinding/tests/Pest.php

@@ -0,0 +1,16 @@
+<?php
+
+declare(strict_types=1);
+
+use Tests\Type\Fixtures\CustomTestCase;
+use Tests\Type\Fixtures\HelperTrait;
+
+// @note: a trait bound without in() applies to every test file, but binds no test case class.
+pest()->use(HelperTrait::class);
+
+pest()->extend(CustomTestCase::class)->in('../modules/*/tests/Feature');
+
+// @note: a hook-only chain binds neither a class nor a trait.
+pest()->beforeEach(function (): void {
+    //
+})->in('../modules/*/tests');

tests/GlobalTraitBindingTestCase.php

@@ -0,0 +1,22 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Tests;
+
+use Override;
+use PHPStan\Testing\TypeInferenceTestCase;
+
+abstract class GlobalTraitBindingTestCase extends TypeInferenceTestCase
+{
+    /**
+     * @return string[]
+     */
+    #[Override]
+    final public static function getAdditionalConfigFiles(): array
+    {
+        return [
+            __DIR__.'/Type/global-trait-binding-extension.neon',
+        ];
+    }
+}

tests/Type/GlobalTraitBindingTest.php

@@ -0,0 +1,12 @@
+<?php
+
+declare(strict_types=1);
+
+use Tests\GlobalTraitBindingTestCase;
+
+test('a bare test() keeps the declared type when only global traits cover the file', function (string $assertType, string $file, mixed ...$args): void {
+    $this->assertFileAsserts($assertType, $file, ...$args);
+})->with(function (): Iterator {
+    yield from GlobalTraitBindingTestCase::gatherAssertTypes(__DIR__.'/../Fixtures/GlobalTraitBinding/modules/Billing/tests/Helpers.php');
+    yield from GlobalTraitBindingTestCase::gatherAssertTypes(__DIR__.'/../Fixtures/GlobalTraitBinding/modules/Billing/tests/Feature/billing-test-function.php');
+});

tests/Type/global-trait-binding-extension.neon

@@ -0,0 +1,6 @@
+includes:
+    - ../../extension.neon
+
+parameters:
+    paths:
+        - ../Fixtures/GlobalTraitBinding