Improves compilation of custom functions declared within a component'…

…s template

CHANGELOG.md

@@ -1,5 +1,9 @@
 # Changelog
 
+## Unreleased
+
+- Improves compilation of custom functions declared within a component's template
+
 ## [v1.0.6](https://github.com/Stillat/dagger/compare/v1.0.5...v1.0.6) - 2025-01-31
 
 - Corrects an issue where Blade stack compilation results in array index errors

src/Compiler/ComponentCompiler.php

@@ -8,6 +8,7 @@
 use Stillat\Dagger\Compiler\ComponentStages\ExtractsRenderCalls;
 use Stillat\Dagger\Compiler\ComponentStages\RemoveUseStatements;
 use Stillat\Dagger\Compiler\ComponentStages\ResolveNamespaces;
+use Stillat\Dagger\Compiler\ComponentStages\RewriteFunctions;
 use Stillat\Dagger\Compiler\Concerns\CompilesPhp;
 use Stillat\Dagger\Parser\PhpParser;
 
@@ -42,6 +43,7 @@ public function compile(string $component): string
                 ResolveNamespaces::class,
                 RemoveUseStatements::class,
                 new ExtractsRenderCalls($this),
+                RewriteFunctions::class,
             ])
             ->thenReturn();
 

src/Compiler/ComponentStages/RewriteFunctions.php

@@ -0,0 +1,27 @@
+<?php
+
+namespace Stillat\Dagger\Compiler\ComponentStages;
+
+use Closure;
+use PhpParser\NodeTraverser;
+use Stillat\Dagger\Parser\Visitors\FindFunctionsVisitor;
+use Stillat\Dagger\Parser\Visitors\RenameFunctionVisitor;
+
+class RewriteFunctions extends AbstractStage
+{
+    public function handle($ast, Closure $next)
+    {
+        $traverser = new NodeTraverser;
+
+        $finder = new FindFunctionsVisitor;
+        $traverser->addVisitor($finder);
+        $traverser->traverse($ast);
+
+        $traverser->removeVisitor($finder);
+
+        $modifyFunctionsVisitor = new RenameFunctionVisitor($finder->getFunctionNames());
+        $traverser->addVisitor($modifyFunctionsVisitor);
+
+        return $next($traverser->traverse($ast));
+    }
+}

src/Parser/Visitors/FindFunctionsVisitor.php

@@ -0,0 +1,25 @@
+<?php
+
+namespace Stillat\Dagger\Parser\Visitors;
+
+use PhpParser\Node;
+use PhpParser\NodeVisitorAbstract;
+
+class FindFunctionsVisitor extends NodeVisitorAbstract
+{
+    protected array $functionNames = [];
+
+    public function enterNode(Node $node)
+    {
+        if (! $node instanceof Node\Stmt\Function_) {
+            return;
+        }
+
+        $this->functionNames[] = $node->name->toString();
+    }
+
+    public function getFunctionNames(): array
+    {
+        return $this->functionNames;
+    }
+}

src/Parser/Visitors/RenameFunctionVisitor.php

@@ -0,0 +1,70 @@
+<?php
+
+namespace Stillat\Dagger\Parser\Visitors;
+
+use PhpParser\Node;
+use PhpParser\NodeVisitorAbstract;
+use Stillat\Dagger\Support\Utils;
+
+class RenameFunctionVisitor extends NodeVisitorAbstract
+{
+    protected array $functionNames = [];
+
+    public function __construct(array $functionNames)
+    {
+        $this->functionNames = $this->buildFunctionNameMap($functionNames);
+    }
+
+    protected function buildFunctionNameMap(array $functionNames): array
+    {
+        return collect($functionNames)
+            ->mapWithKeys(function ($name) {
+                return [$name => $name.'_'.Utils::makeRandomString()];
+            })
+            ->all();
+    }
+
+    public function enterNode(Node $node)
+    {
+        if (! $node instanceof Node\Expr\FuncCall || ! $node->name instanceof Node\Name) {
+            return;
+        }
+
+        $functionName = $node->name->toString();
+
+        if (! isset($this->functionNames[$functionName])) {
+            return;
+        }
+
+        $node->name = new Node\Name($this->functionNames[$functionName]);
+    }
+
+    public function leaveNode(Node $node)
+    {
+        if (! $node instanceof Node\Stmt\Function_) {
+            return null;
+        }
+
+        $functionName = $node->name->toString();
+
+        if (! isset($this->functionNames[$functionName])) {
+            return null;
+        }
+
+        $newFunctionName = $this->functionNames[$functionName];
+
+        $node->name = new Node\Identifier($newFunctionName);
+
+        return new Node\Stmt\If_(
+            new Node\Expr\BooleanNot(
+                new Node\Expr\FuncCall(
+                    new Node\Name('function_exists'),
+                    [new Node\Arg(new Node\Scalar\String_($newFunctionName))]
+                )
+            ),
+            [
+                'stmts' => [$node],
+            ]
+        );
+    }
+}

tests/Compiler/CustomFunctionsTest.php

@@ -0,0 +1,22 @@
+<?php
+
+use Stillat\Dagger\Tests\CompilerTestCase;
+
+uses(CompilerTestCase::class);
+
+test('custom functions in a component are compiled', function () {
+    $template = <<<'BLADE'
+@for ($i = 0; $i < 5; $i++)
+<c-functions.declared title="The Title: {{ $i }}" />
+@endfor
+BLADE;
+
+    $expected = <<<'EXPECTED'
+THE TITLE: 0THE TITLE: 1THE TITLE: 2THE TITLE: 3THE TITLE: 4
+EXPECTED;
+
+    $this->assertSame(
+        $expected,
+        $this->render($template)
+    );
+});

tests/resources/components/functions/declared.blade.php

@@ -0,0 +1,9 @@
+<?php
+\Stillat\Dagger\component()->props(['title'])->trimOutput();
+
+function toUpper($value) {
+  return mb_strtoupper($value);
+}
+?>
+
+{{ toUpper($title) }}