Pass options in to compiler at construction instead of with each pass

We're going to use 'options' to also hold some mutated state, so let's just keep it simple

app/Commands/Stack/Compile.php

@@ -39,9 +39,10 @@ class Compile extends Command
 
 		$serializer = $this->getSerializer();
 		$unserializer = $this->getUnserializer();
-		$engine->setSerializer($serializer)->setUnserializer($unserializer)->setCompiler(new \App\Engine\Cfnpp());
+		$options = null;
+		$engine->setSerializer($serializer)->setUnserializer($unserializer)->setCompiler(new \App\Engine\Cfnpp($options = new \App\Engine\CfnppOptions()));
 
-		$output = $engine->process($this->argument('in_file'), new \App\Engine\CfnppOptions());
+		$output = $engine->process($this->argument('in_file'), $options);
 
 		file_put_contents($this->argument('out_file'), $output);
 	}

app/Engine/Cfnpp.php

@@ -44,23 +44,13 @@ class Cfnpp implements ICompile
 	 */
 	protected $merge_functions;
 
-	public function __construct()
+	public function __construct(IOptions $options)
 	{
 		$this->document = new Document();
 		$this->functions = [];
 
-		// Suppress, we'll move these out of here later and clean them up.
-		// @phan-suppress-next-line PhanPluginUnknownClosureReturnType
-		$this->registerMergeFunction('Replace', static function(Node $orig_p, Node $tgt_p, Node $t) {
-			// todo: nodefunctionvalue
-
-			$repl = new Node(null, $tgt_p->hasName() ? $tgt_p->getName() : null);
-			$repl->setChildren($t->getChildren());
-			return $repl;
-		});
-		// @phan-suppress-next-line PhanPluginUnknownClosureReturnType
-		$this->registerFunction('Unset', static function(Node $node, Node $func) {
-		});
+		$cfnpp_functions = new CfnppFunctions($this, $options);
+		$cfnpp_functions->register($this);
 	}
 
 	/**
@@ -113,10 +103,9 @@ class Cfnpp implements ICompile
 	 * Apply a new document to the current state.
 	 *
 	 * @param  Document $document
-	 * @param  IOptions $options
 	 * @return void
 	 */
-	public function compile(Document $document, IOptions $options): void
+	public function compile(Document $document): void
 	{
 		$this->runMergeFunctions($this->document, $document);
 		$this->merge($this->document, $document);

app/Engine/CfnppFunctions.php

@@ -0,0 +1,95 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Engine;
+
+use App\Dom\Document;
+use App\Dom\Node;
+use App\Dom\NodeFunction;
+use App\Dom\NodeFunctionValue;
+
+/**
+ * Functions available in a cfnpp document.
+ *
+ * @author Adam Pippin <hello@adampippin.ca>
+ */
+class CfnppFunctions
+{
+	/**
+	 * cfnpp compiler.
+	 * @var Cfnpp
+	 */
+	protected $compiler;
+
+	/**
+	 * cfnpp compiler options, stores state.
+	 * @var CfnppOptions
+	 */
+	protected $options;
+
+	public function __construct(Cfnpp $compiler, CfnppOptions $options)
+	{
+	}
+
+	/**
+	 * Examines this class with reflection and registers all functions on a cfnpp
+	 * compiler instance.
+	 *
+	 * @param  Cfnpp $compiler
+	 * @return void
+	 */
+	public function register(Cfnpp $compiler): void
+	{
+		$reflection = new \ReflectionClass(static::class);
+		$methods = $reflection->getMethods();
+
+		foreach ($methods as $method)
+		{
+			if (!stristr($method->name, '_'))
+			{
+				continue;
+			}
+			[$method_type, $method_name] = explode('_', $method->name, 2);
+			switch ($method_type)
+			{
+				case 'mf':
+					$compiler->registerMergeFunction($method_name, [$this, $method->name]);
+					break;
+				case 'f':
+					$compiler->registerFunction($method_name, [$this, $method->name]);
+					break;
+			}
+		}
+	}
+
+	/**
+	 * Replace all children nodes in original with those from target, rather than
+	 * merging them.
+	 *
+	 * @param  Node         $original
+	 * @param  Node         $target
+	 * @param  NodeFunction $function
+	 * @return ?Node
+	 */
+	public function mf_replace(Node $original, Node $target, NodeFunction $function): ?Node
+	{
+		// TODO: Deal with nodefunctionvalue
+
+		$replacement = new Node(null, $target->hasName() ? $target->getName() : null);
+		$replacement->setChildren($function->getChildren());
+		return $replacement;
+	}
+
+	/**
+	 * Unset a node, completely removing it from the document.
+	 *
+	 * @param  Node         $node
+	 * @param  NodeFunction $function
+	 * @return ?Node
+	 */
+	public function f_unset(Node $node, NodeFunction $function): ?Node
+	{
+		return null;
+	}
+}

app/Engine/ICompile.php

@@ -24,10 +24,9 @@ interface ICompile
 	 * using the one passed in as instructions.
 	 *
 	 * @param  \App\Dom\Document $document document to compile
-	 * @param  IOptions          $options  options to control compilation process
 	 * @return void
 	 */
-	public function compile(\App\Dom\Document $document, IOptions $options): void;
+	public function compile(\App\Dom\Document $document): void;
 
 	/**
 	 * Retrieve the current result.