feat: adds toUseTraits expectation

src/Expectation.php

@@ -611,6 +611,41 @@ final class Expectation
         );
     }
 
+    /**
+     * Asserts that the given expectation target to use the given trait.
+     *
+     * @param  string $trait
+     */
+    public function toUseTrait(string $trait): ArchExpectation
+    {
+        return $this->toUseTraits($trait);
+    }
+
+    /**
+     * Asserts that the given expectation target to use the given traits.
+     *
+     * @param  array<int, string>|string  $traits
+     */
+    public function toUseTraits(array|string $traits): ArchExpectation
+    {
+        $traits = is_array($traits) ? $traits : [$traits];
+
+        return Targeted::make(
+            $this,
+            function (ObjectDescription $object) use ($traits): bool {
+                foreach ($traits as $trait) {
+                    if (! in_array($trait, $object->reflectionClass->getTraitNames(), true)) {
+                        return false;
+                    }
+                }
+
+                return true;
+            },
+            "to use traits '".implode("', '", $traits)."'",
+            FileLineFinder::where(fn (string $line): bool => str_contains($line, 'class')),
+        );
+    }
+
     /**
      * Asserts that the given expectation target to not implement any interfaces.
      */
@@ -668,6 +703,8 @@ final class Expectation
         );
     }
 
+
+
     /**
      * Asserts that the given expectation target to implement the given interfaces.
      *

src/Expectations/OppositeExpectation.php

@@ -252,6 +252,41 @@ final class OppositeExpectation
         );
     }
 
+    /**
+     * Asserts that the given expectation target not to use the given trait.
+     *
+     * @param  string $trait
+     */
+    public function toUseTrait(string $trait): ArchExpectation
+    {
+        return $this->toUseTraits($trait);
+    }
+
+    /**
+     * Asserts that the given expectation target not to use the given traits.
+     *
+     * @param  array<int, string>|string  $traits
+     */
+    public function toUseTraits(array|string $traits): ArchExpectation
+    {
+        $traits = is_array($traits) ? $traits : [$traits];
+
+        return Targeted::make(
+            $this->original,
+            function (ObjectDescription $object) use ($traits): bool {
+                foreach ($traits as $trait) {
+                    if (in_array($trait, $object->reflectionClass->getTraitNames(), true)) {
+                        return false;
+                    }
+                }
+
+                return true;
+            },
+            "to use traits '" . implode("', '", $traits) . "'",
+            FileLineFinder::where(fn(string $line): bool => str_contains($line, 'class')),
+        );
+    }
+
     /**
      * Asserts that the given expectation target not to implement the given interfaces.
      *

tests/Features/Expect/toUseTrait.php

@@ -0,0 +1,16 @@
+<?php
+
+use Pest\Arch\Exceptions\ArchExpectationFailedException;
+
+test('pass', function () {
+    expect('Pest\Expectations\HigherOrderExpectation')->toUseTrait('Pest\Concerns\Retrievable')
+        ->and('Pest\Expectations\EachExpectation')->not->toUseTrait('Pest\Concerns\Retrievable');
+});
+
+test('failures', function () {
+    expect('Pest\Expectations\EachExpectation')->toUseTrait('Pest\Concerns\Foo');
+})->throws(ArchExpectationFailedException::class);
+
+test('not failures', function () {
+    expect('Pest\Expectations\HigherOrderExpectation')->not->toUseTrait('Pest\Concerns\Retrievable');
+})->throws(ArchExpectationFailedException::class);