feat: Implement trait aggregation in relationships and add TraitAggregationTest for validation

Author: tasuku43

src/ClassDiagramRenderer/ClassDiagramBuilder.php

@@ -5,6 +5,7 @@
 
 use Exception;
 use Tasuku43\MermaidClassDiagram\ClassDiagramRenderer\Node\NodeParser;
+use Tasuku43\MermaidClassDiagram\ClassDiagramRenderer\Node\Trait_ as DiagramTrait;
 
 class ClassDiagramBuilder
 {

src/ClassDiagramRenderer/Node/Node.php

@@ -57,20 +57,7 @@ public function useTrait(Node $trait): void
         $this->traits->add($trait);
     }
 
-    /**
-     * Return trait-derived compositions and dependencies for this node.
-     * @return array{array<string, Node>, array<string, Node>} [compositions, dependencies]
-     */
-    public function traitAggregates(): array
-    {
-        $traitCompositions = [];
-        $traitDependencies = [];
-        $visitedTraits = [];
-        foreach ($this->traits->getAllNodes() as $traitNode) {
-            $this->collectTraitRelations($traitNode, $visitedTraits, $traitCompositions, $traitDependencies);
-        }
-        return [$traitCompositions, $traitDependencies];
-    }
+    // Intentionally left without public API; trait aggregation is done in relationships()
 
     public function nodeName(): string
     {

src/ClassDiagramRenderer/Node/NodeParser.php

@@ -4,9 +4,7 @@
 namespace Tasuku43\MermaidClassDiagram\ClassDiagramRenderer\Node;
 
 use Exception;
-use PhpParser\Node;
 use PhpParser\Node\Stmt;
-use PhpParser\Node\Stmt\ClassLike;
 use PhpParser\NodeFinder;
 use PhpParser\NodeTraverser;
 use PhpParser\NodeVisitor\NameResolver;
@@ -17,6 +15,7 @@
 use Tasuku43\MermaidClassDiagram\ClassDiagramRenderer\Node\Connector\DependencyConnector;
 use Tasuku43\MermaidClassDiagram\ClassDiagramRenderer\Node\Connector\InheritanceConnector;
 use Tasuku43\MermaidClassDiagram\ClassDiagramRenderer\Node\Connector\RealizationConnector;
+use Tasuku43\MermaidClassDiagram\ClassDiagramRenderer\Node\Connector\TraitUsageConnector;
 use Tasuku43\MermaidClassDiagram\ClassDiagramRenderer\Node\Exception\CannnotParseToClassLikeException;
 use Tasuku43\MermaidClassDiagram\ClassDiagramRenderer\Node\Node as ClassDiagramNode;
 
@@ -37,6 +36,7 @@ public function __construct(
             fn(Stmt\Interface_|Stmt\Class_|Stmt\Enum_|Stmt\Trait_ $classLike, ClassDiagramNode $classDiagramNode) => RealizationConnector::parse($classLike, $classDiagramNode),
             fn(Stmt\Interface_|Stmt\Class_|Stmt\Enum_|Stmt\Trait_ $classLike, ClassDiagramNode $classDiagramNode) => CompositionConnector::parse($nodeFinder, $classLike, $classDiagramNode),
             fn(Stmt\Interface_|Stmt\Class_|Stmt\Enum_|Stmt\Trait_ $classLike, ClassDiagramNode $classDiagramNode) => DependencyConnector::parse($nodeFinder, $classLike, $classDiagramNode),
+            fn(Stmt\Interface_|Stmt\Class_|Stmt\Enum_|Stmt\Trait_ $classLike, ClassDiagramNode $classDiagramNode) => TraitUsageConnector::parse($nodeFinder, $classLike, $classDiagramNode),
         ];
     }
 
@@ -111,7 +111,8 @@ private function parseClassLikes(string $code): array
         $validClassLikes = array_filter($allClassLikes, function ($node) {
             return $node instanceof Stmt\Class_ 
                 || $node instanceof Stmt\Interface_
-                || $node instanceof Stmt\Enum_;
+                || $node instanceof Stmt\Enum_
+                || $node instanceof Stmt\Trait_;
         });
 
         if (empty($validClassLikes)) {
@@ -132,6 +133,7 @@ private function createClassDiagramNodeFromClassLike($classLike): ClassDiagramNo
                 : new Class_((string)$classLike->name->name),
             $classLike instanceof Stmt\Interface_ => new Interface_((string)$classLike->name->name),
             $classLike instanceof Stmt\Enum_ => new Enum_((string)$classLike->name->name),
+            $classLike instanceof Stmt\Trait_ => new Trait_((string)$classLike->name->name),
             default => throw new Exception('Unexpected match value: ' . get_class($classLike))
         };
     }

tests/ClassDiagramRenderer/ClassDiagramBuilderTest.php

@@ -40,6 +40,11 @@ classDiagram
     class AbstractController {
         <<abstract>>
     }
+    class AuditLogger {
+    }
+    class RepositoryAwareTrait {
+        <<trait>>
+    }
     class User {
     }
     class UserController {
@@ -55,12 +60,16 @@ class UserStatus {
         <<enum>>
     }
 
+    RepositoryAwareTrait *-- AuditLogger: composition
+    RepositoryAwareTrait ..> User: dependency
+    RepositoryAwareTrait *-- UserRepositoryInterface: composition
     User *-- UserStatus: composition
     AbstractController <|-- UserController: inheritance
     UserController *-- UserService: composition
     UserRepository ..> User: dependency
     UserRepositoryInterface <|.. UserRepository: realization
     UserRepositoryInterface ..> User: dependency
+    UserService *-- AuditLogger: composition
     UserService ..> InvalidArgumentException: dependency
     UserService ..> User: dependency
     UserService *-- UserRepositoryInterface: composition
@@ -104,6 +113,11 @@ classDiagram
     class AbstractController {
         <<abstract>>
     }
+    class AuditLogger {
+    }
+    class RepositoryAwareTrait {
+        <<trait>>
+    }
     class User {
     }
     class UserController {
@@ -119,10 +133,13 @@ class UserStatus {
         <<enum>>
     }
 
+    RepositoryAwareTrait *-- AuditLogger: composition
+    RepositoryAwareTrait *-- UserRepositoryInterface: composition
     User *-- UserStatus: composition
     AbstractController <|-- UserController: inheritance
     UserController *-- UserService: composition
     UserRepositoryInterface <|.. UserRepository: realization
+    UserService *-- AuditLogger: composition
     UserService *-- UserRepositoryInterface: composition
 
 EOT;

tests/ClassDiagramRenderer/Node/TraitAggregationTest.php

@@ -0,0 +1,59 @@
+<?php
+declare(strict_types=1);
+
+namespace Tasuku43\Tests\MermaidClassDiagram\ClassDiagramRenderer\Node;
+
+use PHPUnit\Framework\TestCase;
+use Tasuku43\MermaidClassDiagram\ClassDiagramRenderer\Node\Class_ as DiagramClass;
+use Tasuku43\MermaidClassDiagram\ClassDiagramRenderer\Node\Trait_ as DiagramTrait;
+use Tasuku43\MermaidClassDiagram\ClassDiagramRenderer\Node\Relationship\Composition;
+use Tasuku43\MermaidClassDiagram\ClassDiagramRenderer\Node\Relationship\Dependency;
+
+class TraitAggregationTest extends TestCase
+{
+    public function testClassInheritsTraitDependenciesAndCompositions(): void
+    {
+        $trait = new DiagramTrait('T');
+        $dep = new DiagramClass('Dep');
+        $prop = new DiagramClass('Prop');
+        $trait->depend($dep);
+        $trait->composition($prop);
+
+        $using = new DiagramClass('Using');
+        $using->useTrait($trait);
+
+        $relationships = $using->relationships();
+
+        $this->assertTrue($this->hasRelationship($relationships, Composition::class, 'Using', 'Prop'));
+        $this->assertTrue($this->hasRelationship($relationships, Dependency::class, 'Using', 'Dep'));
+    }
+
+    public function testNestedTraitDependenciesAreAggregated(): void
+    {
+        $t1 = new DiagramTrait('T1');
+        $t1->depend(new DiagramClass('D1'));
+
+        $t2 = new DiagramTrait('T2');
+        $t2->useTrait($t1);
+
+        $using = new DiagramClass('Using');
+        $using->useTrait($t2);
+
+        $relationships = $using->relationships();
+        $this->assertTrue($this->hasRelationship($relationships, Dependency::class, 'Using', 'D1'));
+    }
+
+    private function hasRelationship(array $relationships, string $class, string $from, string $to): bool
+    {
+        foreach ($relationships as $rel) {
+            if ($rel instanceof $class) {
+                $render = $rel->render();
+                if (str_contains($render, $from) && str_contains($render, $to)) {
+                    return true;
+                }
+            }
+        }
+        return false;
+    }
+}
+

tests/data/Project/Service/UserService.php

@@ -9,6 +9,7 @@
 
 class UserService
 {
+    use RepositoryAwareTrait;
     public function __construct(
         private UserRepositoryInterface $userRepository
     ) {