Restore partial and helper resolver options

Closes #1

Author: theodorejb

README.md

@@ -65,7 +65,9 @@ echo $template(['first' => 'John']); // Error: Runtime: [last] does not exist
 * `ignoreStandalone`: Disables standalone tag removal. When set, blocks and partials that are on their own line will not remove the whitespace on that line.
 * `explicitPartialContext`: Disables implicit context for partials. When enabled, partials that are not passed a context value will execute against an empty object.
 * `helpers`: Provide a key => value array of custom helper functions.
+* `helperResolver`: A closure which will be called for any helper not in the `helpers` array to return a function for it.
 * `partials`: Provide a key => value array of custom partial templates.
+* `partialResolver`: A closure which will be called for any partial not in the `partials` array to return a template for it.
 
 ## Custom Helpers
 

composer.json

@@ -25,7 +25,7 @@
     "require-dev": {
         "friendsofphp/php-cs-fixer": "^3.75",
         "jbboehr/handlebars-spec": "dev-master",
-        "phpstan/phpstan": "^2.1.12",
+        "phpstan/phpstan": "^2.1.14",
         "phpunit/phpunit": "^11.5"
     },
     "autoload": {

composer.lock

@@ -2,6 +2,8 @@
 
 namespace DevTheorem\Handlebars;
 
+use Closure;
+
 /**
  * @internal
  */
@@ -18,9 +20,11 @@ final class Context
      * @param array<string, true> $usedHelpers
      * @param array<mixed> $parsed
      * @param array<string, string> $partials
+     * @param null|Closure(Context, string):(string|null) $partialResolver
      * @param array<mixed> $partialBlock
      * @param array<mixed> $inlinePartial
      * @param array<string, callable> $helpers
+     * @param null|Closure(Context, string):(Closure|null) $helperResolver
      */
     public function __construct(
         public readonly Options $options,
@@ -42,9 +46,11 @@ public function __construct(
         public bool $compile = false,
         public array $parsed = [],
         public array $partials = [],
+        public ?Closure $partialResolver = null,
         public array $partialBlock = [],
         public array $inlinePartial = [],
         public array $helpers = [],
+        public ?Closure $helperResolver = null,
         public string|false $rawBlock = false,
         public readonly string $startChar = '{',
         public readonly string $separator = '.',
@@ -56,7 +62,9 @@ public function __construct(
         public readonly string $fEnd = ';',
     ) {
         $this->partials = $options->partials;
+        $this->partialResolver = $options->partialResolver;
         $this->helpers = $options->helpers;
+        $this->helperResolver = $options->helperResolver;
     }
 
     /**

src/Context.php

@@ -2,11 +2,15 @@
 
 namespace DevTheorem\Handlebars;
 
+use Closure;
+
 readonly class Options
 {
     /**
      * @param array<string, callable> $helpers
+     * @param null|Closure(Context, string):(Closure|null) $helperResolver
      * @param array<string, string> $partials
+     * @param null|Closure(Context, string):(string|null) $partialResolver
      */
     public function __construct(
         public bool $knownHelpersOnly = false,
@@ -16,6 +20,8 @@ public function __construct(
         public bool $ignoreStandalone = false,
         public bool $explicitPartialContext = false,
         public array $helpers = [],
+        public ?Closure $helperResolver = null,
         public array $partials = [],
+        public ?Closure $partialResolver = null,
     ) {}
 }

src/Options.php

@@ -55,6 +55,9 @@ public static function resolve(Context $context, string &$name): ?string
         if (isset($context->partials[$name])) {
             return $context->partials[$name];
         }
+        if ($context->partialResolver) {
+            return ($context->partialResolver)($context, $name);
+        }
         return null;
     }
 

src/Partial.php

@@ -658,7 +658,20 @@ public static function resolveHelper(Context $context, array $vars): bool
             return false;
         }
 
-        return isset($context->helpers[$vars[0][0]]);
+        $name = $vars[0][0];
+        if (isset($context->helpers[$name])) {
+            return true;
+        }
+
+        if ($context->helperResolver) {
+            $helper = ($context->helperResolver)($context, $name);
+            if ($helper) {
+                $context->helpers[$name] = $helper;
+                return true;
+            }
+        }
+
+        return false;
     }
 
     /**

src/Validator.php

@@ -2,6 +2,7 @@
 
 namespace DevTheorem\Handlebars\Test;
 
+use DevTheorem\Handlebars\Context;
 use DevTheorem\Handlebars\Handlebars;
 use DevTheorem\Handlebars\HelperOptions;
 use DevTheorem\Handlebars\Options;
@@ -829,6 +830,29 @@ public static function issueProvider(): array
                 'expected' => '3',
             ],
 
+            [
+                'id' => 201,
+                'template' => '{{foo "world"}}',
+                'options' => new Options(
+                    helperResolver: function () {
+                        return fn(string $name) => "Hello, $name";
+                    },
+                ),
+                'expected' => 'Hello, world',
+            ],
+            [
+                'id' => 201,
+                'template' => '{{#foo "test"}}World{{/foo}}',
+                'options' => new Options(
+                    helperResolver: function (Context $cx, string $name) {
+                        return function ($name, HelperOptions $options) {
+                            return "$name = " . $options->fn();
+                        };
+                    },
+                ),
+                'expected' => 'test = World',
+            ],
+
             [
                 'id' => 204,
                 'template' => '{{#> test name="A"}}B{{/test}}{{#> test name="C"}}D{{/test}}',
@@ -2030,6 +2054,16 @@ public static function issueProvider(): array
                 'expected' => 'inline\'partial',
             ],
 
+            [
+                'template' => '{{>foo}} and {{>bar}}',
+                'options' => new Options(
+                    partialResolver: function (Context $context, string $name) {
+                        return "PARTIAL: $name";
+                    },
+                ),
+                'expected' => 'PARTIAL: foo and PARTIAL: bar',
+            ],
+
             [
                 'template' => "{{#> testPartial}}\n ERROR: testPartial is not found!\n  {{#> innerPartial}}\n   ERROR: innerPartial is not found!\n   ERROR: innerPartial is not found!\n  {{/innerPartial}}\n ERROR: testPartial is not found!\n {{/testPartial}}",
                 'expected' => " ERROR: testPartial is not found!\n   ERROR: innerPartial is not found!\n   ERROR: innerPartial is not found!\n ERROR: testPartial is not found!\n",