minor #4250 Add return type isTraitable (ruudk)

This PR was squashed before being merged into the 3.x branch.

Discussion
----------

Add return type `isTraitable`

I'd like to do this for more methods that are exposed in the compiled code. This will ease static analysis as there are less errors that are coming from Twig.

This is just a first small PR to see if this is acceptable 😊

Commits
-------

bb8b9c1 Add return type `isTraitable`

src/Node/ModuleNode.php

@@ -115,7 +115,7 @@ protected function compileGetParent(Compiler $compiler)
         $parent = $this->getNode('parent');
 
         $compiler
-            ->write("protected function doGetParent(array \$context)\n", "{\n")
+            ->write("protected function doGetParent(array \$context): bool|string|Template|TemplateWrapper\n", "{\n")
             ->indent()
             ->addDebugInfo($parent)
             ->write('return ')
@@ -160,7 +160,9 @@ protected function compileClassHeader(Compiler $compiler)
                 ->write("use Twig\Sandbox\SecurityNotAllowedFilterError;\n")
                 ->write("use Twig\Sandbox\SecurityNotAllowedFunctionError;\n")
                 ->write("use Twig\Source;\n")
-                ->write("use Twig\Template;\n\n")
+                ->write("use Twig\Template;\n")
+                ->write("use Twig\TemplateWrapper;\n")
+                ->write("\n")
             ;
         }
         $compiler
@@ -170,8 +172,11 @@ protected function compileClassHeader(Compiler $compiler)
             ->raw(" extends Template\n")
             ->write("{\n")
             ->indent()
-            ->write("private \$source;\n")
-            ->write("private \$macros = [];\n\n")
+            ->write("private Source \$source;\n")
+            ->write("/**\n")
+            ->write(" * @var array<string, Template>\n")
+            ->write(" */\n")
+            ->write("private array \$macros = [];\n\n")
         ;
     }
 
@@ -377,7 +382,7 @@ protected function compileGetTemplateName(Compiler $compiler)
             ->write("/**\n")
             ->write(" * @codeCoverageIgnore\n")
             ->write(" */\n")
-            ->write("public function getTemplateName()\n", "{\n")
+            ->write("public function getTemplateName(): string\n", "{\n")
             ->indent()
             ->write('return ')
             ->repr($this->getSourceContext()->getName())
@@ -434,7 +439,7 @@ protected function compileIsTraitable(Compiler $compiler)
             ->write("/**\n")
             ->write(" * @codeCoverageIgnore\n")
             ->write(" */\n")
-            ->write("public function isTraitable()\n", "{\n")
+            ->write("public function isTraitable(): bool\n", "{\n")
             ->indent()
             ->write("return false;\n")
             ->outdent()
@@ -448,7 +453,7 @@ protected function compileDebugInfo(Compiler $compiler)
             ->write("/**\n")
             ->write(" * @codeCoverageIgnore\n")
             ->write(" */\n")
-            ->write("public function getDebugInfo()\n", "{\n")
+            ->write("public function getDebugInfo(): array\n", "{\n")
             ->indent()
             ->write(\sprintf("return %s;\n", str_replace("\n", '', var_export(array_reverse($compiler->getDebugInfo(), true), true))))
             ->outdent()
@@ -459,7 +464,7 @@ protected function compileDebugInfo(Compiler $compiler)
     protected function compileGetSourceContext(Compiler $compiler)
     {
         $compiler
-            ->write("public function getSourceContext()\n", "{\n")
+            ->write("public function getSourceContext(): Source\n", "{\n")
             ->indent()
             ->write('return new Source(')
             ->string($compiler->getEnvironment()->isDebug() ? $this->getSourceContext()->getCode() : '')

src/Template.php

@@ -52,24 +52,20 @@ public function __construct(Environment $env)
 
     /**
      * Returns the template name.
-     *
-     * @return string The template name
      */
-    abstract public function getTemplateName();
+    abstract public function getTemplateName(): string;
 
     /**
      * Returns debug information about the template.
      *
-     * @return array Debug information
+     * @return array<int, int> Debug information
      */
-    abstract public function getDebugInfo();
+    abstract public function getDebugInfo(): array;
 
     /**
      * Returns information about the original template source code.
-     *
-     * @return Source
      */
-    abstract public function getSourceContext();
+    abstract public function getSourceContext(): Source;
 
     /**
      * Returns the parent template.
@@ -107,12 +103,12 @@ public function getParent(array $context)
         return $this->parents[$parent];
     }
 
-    protected function doGetParent(array $context)
+    protected function doGetParent(array $context): bool|string|self|TemplateWrapper
     {
         return false;
     }
 
-    public function isTraitable()
+    public function isTraitable(): bool
     {
         return true;
     }

tests/Node/ModuleTest.php

@@ -23,6 +23,8 @@
 use Twig\Node\SetNode;
 use Twig\Node\TextNode;
 use Twig\Source;
+use Twig\Template;
+use Twig\TemplateWrapper;
 use Twig\Test\NodeTestCase;
 
 class ModuleTest extends NodeTestCase
@@ -73,12 +75,16 @@ public function getTests()
 use Twig\Sandbox\SecurityNotAllowedFunctionError;
 use Twig\Source;
 use Twig\Template;
+use Twig\TemplateWrapper;
 
 /* foo.twig */
 class __TwigTemplate_%x extends Template
 {
-    private \$source;
-    private \$macros = [];
+    private Source \$source;
+    /**
+     * @var array<string, Template>
+     */
+    private array \$macros = [];
 
     public function __construct(Environment \$env)
     {
@@ -103,20 +109,20 @@ protected function doDisplay(array \$context, array \$blocks = [])
     /**
      * @codeCoverageIgnore
      */
-    public function getTemplateName()
+    public function getTemplateName(): string
     {
         return "foo.twig";
     }
 
     /**
      * @codeCoverageIgnore
      */
-    public function getDebugInfo()
+    public function getDebugInfo(): array
     {
-        return array (  38 => 1,);
+        return array (  42 => 1,);
     }
 
-    public function getSourceContext()
+    public function getSourceContext(): Source
     {
         return new Source("", "foo.twig", "");
     }
@@ -145,12 +151,16 @@ public function getSourceContext()
 use Twig\Sandbox\SecurityNotAllowedFunctionError;
 use Twig\Source;
 use Twig\Template;
+use Twig\TemplateWrapper;
 
 /* foo.twig */
 class __TwigTemplate_%x extends Template
 {
-    private \$source;
-    private \$macros = [];
+    private Source \$source;
+    /**
+     * @var array<string, Template>
+     */
+    private array \$macros = [];
 
     public function __construct(Environment \$env)
     {
@@ -162,7 +172,7 @@ public function __construct(Environment \$env)
         ];
     }
 
-    protected function doGetParent(array \$context)
+    protected function doGetParent(array \$context): bool|string|Template|TemplateWrapper
     {
         // line 1
         return "layout.twig";
@@ -181,28 +191,28 @@ protected function doDisplay(array \$context, array \$blocks = [])
     /**
      * @codeCoverageIgnore
      */
-    public function getTemplateName()
+    public function getTemplateName(): string
     {
         return "foo.twig";
     }
 
     /**
      * @codeCoverageIgnore
      */
-    public function isTraitable()
+    public function isTraitable(): bool
     {
         return false;
     }
 
     /**
      * @codeCoverageIgnore
      */
-    public function getDebugInfo()
+    public function getDebugInfo(): array
     {
-        return array (  44 => 1,  42 => 2,  35 => 1,);
+        return array (  48 => 1,  46 => 2,  39 => 1,);
     }
 
-    public function getSourceContext()
+    public function getSourceContext(): Source
     {
         return new Source("", "foo.twig", "");
     }
@@ -236,12 +246,16 @@ public function getSourceContext()
 use Twig\Sandbox\SecurityNotAllowedFunctionError;
 use Twig\Source;
 use Twig\Template;
+use Twig\TemplateWrapper;
 
 /* foo.twig */
 class __TwigTemplate_%x extends Template
 {
-    private \$source;
-    private \$macros = [];
+    private Source \$source;
+    /**
+     * @var array<string, Template>
+     */
+    private array \$macros = [];
 
     public function __construct(Environment \$env)
     {
@@ -253,7 +267,7 @@ public function __construct(Environment \$env)
         ];
     }
 
-    protected function doGetParent(array \$context)
+    protected function doGetParent(array \$context): bool|string|Template|TemplateWrapper
     {
         // line 2
         return \$this->loadTemplate(((true) ? ("foo") : ("foo")), "foo.twig", 2);
@@ -271,28 +285,28 @@ protected function doDisplay(array \$context, array \$blocks = [])
     /**
      * @codeCoverageIgnore
      */
-    public function getTemplateName()
+    public function getTemplateName(): string
     {
         return "foo.twig";
     }
 
     /**
      * @codeCoverageIgnore
      */
-    public function isTraitable()
+    public function isTraitable(): bool
     {
         return false;
     }
 
     /**
      * @codeCoverageIgnore
      */
-    public function getDebugInfo()
+    public function getDebugInfo(): array
     {
-        return array (  44 => 2,  42 => 4,  35 => 2,);
+        return array (  48 => 2,  46 => 4,  39 => 2,);
     }
 
-    public function getSourceContext()
+    public function getSourceContext(): Source
     {
         return new Source("{{ foo }}", "foo.twig", "");
     }

tests/TemplateTest.php

@@ -21,6 +21,7 @@
 use Twig\Sandbox\SecurityPolicy;
 use Twig\Source;
 use Twig\Template;
+use Twig\TemplateWrapper;
 
 class TemplateTest extends TestCase
 {
@@ -443,22 +444,22 @@ public function getTrue()
         return true;
     }
 
-    public function getTemplateName()
+    public function getTemplateName(): string
     {
         return $this->name;
     }
 
-    public function getDebugInfo()
+    public function getDebugInfo() : array
     {
         return [];
     }
 
-    public function getSourceContext()
+    public function getSourceContext() : Source
     {
         return new Source('', $this->getTemplateName());
     }
 
-    protected function doGetParent(array $context)
+    protected function doGetParent(array $context): bool|string|Template|TemplateWrapper
     {
         return false;
     }