Add possibility to add strict_type or other declares on the PhpFile

src/PhpFile.php

@@ -12,6 +12,8 @@
 
 class PhpFile extends DependencyAwareGenerator
 {
+    public const STRICT = 'strict_types';
+
     protected string   $namespace = '';
     protected string   $name;
     protected ?Comment $comment;
@@ -33,14 +35,47 @@ public static function new(string $name = ''): self
         return new self($name);
     }
 
+    public function addDeclare(string $name, $value): self
+    {
+        $this->declares[$name] = Utils::stringify($value);
+
+        return $this;
+    }
+
+    public function removeDeclare(string $name): self
+    {
+        unset($this->declares[$name]);
+
+        return $this;
+    }
+
+    public function addStrict(): self
+    {
+        $this->addDeclare(self::STRICT, 1);
+
+        return $this;
+    }
+
+    public function removeStrict(): self
+    {
+        $this->removeDeclare(self::STRICT);
+
+        return $this;
+    }
+
     public function generate(): string
     {
+        $declareItems = [];
+        foreach ($this->declares as $key => $value) {
+            $declareItems[] = "declare($key=$value);";
+        }
+        $declares = count($declareItems) > 0 ? implode("\n", $declareItems) . "\n" : '';
         $namespace = $this->namespace ? "\nnamespace $this->namespace;\n" : '';
         $classes = implode("\n\n", $this->classes);
 
         return <<<CODE
         <?php
-        $namespace{$this->buildUseStatements()}
+        $declares$namespace{$this->buildUseStatements()}
         $classes
         CODE;
     }

tests/PhpFileTest.php

@@ -24,7 +24,8 @@ public function fullBuild(): PhpFile
         $file = PhpFile::new()
             ->setNamespace('App\Converter')
             ->addUseGroup('Symfony\Validator\Converters', 'NotNull', 'Symfony\Validator\Converters\Length')
-            ->setComment('This file was generated and should not be modified manually.');
+            ->setComment('This file was generated and should not be modified manually.')
+            ->addStrict();
 
         $class = $file->createClass('ArrayConverter')
             ->setAbstract()
@@ -59,6 +60,7 @@ public function fullBuild(): PhpFile
 
         $this->expectOutputString(<<<'CODE'
         <?php
+        declare(strict_types=1);
 
         namespace App\Converter;
 
@@ -109,6 +111,7 @@ private static function getPhpFile(): PhpFile
      */
     public function modifyFile(PhpFile $file): PhpFile
     {
+        $file->removeStrict();
         $file->removeClass('ArrayConverter');
         $file->removeUse('Symfony\Validator\Converters');
         $file->addClass(new PhpClass('YetAnotherClass'));