Add a way of asking for the parsed grammar in Transformer

Author: ryangjchandler

src/Adapters/CommonMark/Transformers/AnnotationsTransformer.php

@@ -0,0 +1,12 @@
+<?php
+
+namespace Phiki\Adapters\CommonMark\Transformers;
+
+use Phiki\Contracts\RequiresGrammarInterface;
+use Phiki\Transformers\AbstractTransformer;
+use Phiki\Transformers\Concerns\RequiresGrammar;
+
+class AnnotationsTransformer extends AbstractTransformer implements RequiresGrammarInterface
+{
+    use RequiresGrammar;
+}

src/Contracts/RequiresGrammarInterface.php

@@ -0,0 +1,13 @@
+<?php
+
+namespace Phiki\Contracts;
+
+use Phiki\Grammar\ParsedGrammar;
+
+interface RequiresGrammarInterface
+{
+    /**
+     * Set the parsed grammar for the transformer.
+     */
+    public function withGrammar(ParsedGrammar $grammar): void;
+}

src/Output/Html/PendingHtmlOutput.php

@@ -3,6 +3,7 @@
 namespace Phiki\Output\Html;
 
 use Closure;
+use Phiki\Contracts\RequiresGrammarInterface;
 use Phiki\Contracts\TransformerInterface;
 use Phiki\Grammar\ParsedGrammar;
 use Phiki\Phast\ClassList;
@@ -173,6 +174,10 @@ public function __toString(): string
 
         foreach ($this->transformers as $transformer) {
             $transformer->withMeta($this->meta);
+
+            if ($transformer instanceof RequiresGrammarInterface) {
+                $transformer->withGrammar($this->grammar);
+            }
         }
 
         [$code] = $this->callTransformerMethod('preprocess', $this->code);

src/Transformers/Concerns/RequiresGrammar.php

@@ -0,0 +1,15 @@
+<?php
+
+namespace Phiki\Transformers\Concerns;
+
+use Phiki\Grammar\ParsedGrammar;
+
+trait RequiresGrammar
+{
+    protected ParsedGrammar $grammar;
+
+    public function withGrammar(ParsedGrammar $grammar): void
+    {
+        $this->grammar = $grammar;
+    }
+}