Partial blocks and inline partials

src/main/php/com/handlebarsjs/BlockHelpers.class.php

@@ -13,6 +13,8 @@ static function __static() {
     self::$byName['unless']= XPClass::forName('com.handlebarsjs.UnlessBlockHelper');
     self::$byName['with']= XPClass::forName('com.handlebarsjs.WithBlockHelper');
     self::$byName['each']= XPClass::forName('com.handlebarsjs.EachBlockHelper');
+    self::$byName['>']= XPClass::forName('com.handlebarsjs.PartialBlockHelper');
+    self::$byName['*inline']= XPClass::forName('com.handlebarsjs.InlinePartialHelper');
   }
 
   /**

src/main/php/com/handlebarsjs/HandlebarsEngine.class.php

@@ -26,14 +26,15 @@
  * @see   http://handlebarsjs.com/
  */
 class HandlebarsEngine {
-  protected $mustache;
+  protected $mustache, $templates;
   protected $builtin= [];
 
   /**
    * Constructor. Initializes builtin helpers.
    */
   public function __construct() {
-    $this->mustache= (new MustacheEngine())->withParser(new HandlebarsParser());
+    $this->templates= new Templates();
+    $this->mustache= (new MustacheEngine())->withTemplates($this->templates)->withParser(new HandlebarsParser());
 
     // This: Access the current value in the context
     $this->setBuiltin('this', function($node, $context, $options) {
@@ -119,7 +120,7 @@ public function withLogger($logger) {
    * @return self this
    */
   public function withTemplates(TemplateLoader $l) {
-    $this->mustache->withTemplates($l);
+    $this->templates->delegate($l);
     return $this;
   }
 

src/main/php/com/handlebarsjs/InlinePartialHelper.class.php

@@ -0,0 +1,38 @@
+<?php namespace com\handlebarsjs;
+
+use com\github\mustache\NodeList;
+
+/**
+ * Partial blocks
+ *
+ * @see   http://handlebarsjs.com/partials.html
+ * @test  xp://com.handlebarsjs.unittest.InlinePartialHelperTest
+ */
+class InlinePartialHelper extends BlockNode {
+
+  /**
+   * Creates a new with block helper
+   *
+   * @param string[] $options
+   * @param com.github.mustache.NodeList $fn
+   * @param com.github.mustache.NodeList $inverse
+   * @param string $start
+   * @param string $end
+   */
+  public function __construct($options= [], NodeList $fn= null, NodeList $inverse= null, $start= '{{', $end= '}}') {
+    parent::__construct('inline', $options, $fn, $inverse, $start, $end);
+  }
+
+  /**
+   * Evaluates this node
+   *
+   * @param  com.github.mustache.Context $context the rendering context
+   * @return string
+   */
+  public function evaluate($context) {
+    $f= $this->options[0];
+    $target= $f($this, $context, []);
+
+    $context->engine->getTemplates()->register($target, $this->fn);
+  }
+}

src/main/php/com/handlebarsjs/PartialBlockHelper.class.php

@@ -0,0 +1,46 @@
+<?php namespace com\handlebarsjs;
+
+use com\github\mustache\NodeList;
+use com\github\mustache\TemplateNotFoundException;
+
+/**
+ * Partial blocks
+ *
+ * @see   http://handlebarsjs.com/partials.html
+ * @test  xp://com.handlebarsjs.unittest.PartialBlockHelperTest
+ */
+class PartialBlockHelper extends BlockNode {
+
+  /**
+   * Creates a new with block helper
+   *
+   * @param string[] $options
+   * @param com.github.mustache.NodeList $fn
+   * @param com.github.mustache.NodeList $inverse
+   * @param string $start
+   * @param string $end
+   */
+  public function __construct($options= [], NodeList $fn= null, NodeList $inverse= null, $start= '{{', $end= '}}') {
+    $template= (string)array_shift($options);
+    parent::__construct($template, $options, $fn, $inverse, $start, $end);
+  }
+
+  /**
+   * Evaluates this node
+   *
+   * @param  com.github.mustache.Context $context the rendering context
+   * @return string
+   */
+  public function evaluate($context) {
+    $templates= $context->engine->getTemplates();
+
+    try {
+      $templates->register('@partial-block', $this->fn);
+      return $context->engine->transform($this->name, $context, $this->start, $this->end, '');
+    } catch (TemplateNotFoundException $e) {
+      return $this->fn->evaluate($context);
+    } finally {
+      $templates->remove('@partial-block');
+    }
+  }
+}

src/main/php/com/handlebarsjs/Templates.class.php

@@ -0,0 +1,39 @@
+<?php namespace com\handlebarsjs;
+
+use com\github\mustache\TemplateLoader;
+use com\github\mustache\TemplateNotFoundException;
+use io\streams\MemoryInputStream;
+
+class Templates implements TemplateLoader {
+  private $templates= [];
+  private $delegate;
+
+  public function delegate($delegate) {
+    $this->delegate= $delegate;
+  }
+
+  public function register($name, $content) {
+    $this->templates[$name]= $content;
+  }
+
+  public function remove($name) {
+    unset($this->templates[$name]);
+  }
+
+  /**
+   * Load a template by a given name
+   *
+   * @param  string $name The template name without file extension
+   * @return io.streams.InputStream
+   * @throws com.github.mustache.TemplateNotFoundException
+   */
+  public function load($name) {
+    if (isset($this->templates[$name])) {
+      return new MemoryInputStream($this->templates[$name]);
+    } else if ($this->delegate) {
+      return $this->delegate->load($name);
+    } else {
+      throw new TemplateNotFoundException('Cannot find template '.$name);
+    }
+  }
+}

src/test/php/com/handlebarsjs/unittest/HelperTest.class.php

@@ -1,8 +1,15 @@
 <?php namespace com\handlebarsjs\unittest;
 
 use com\handlebarsjs\HandlebarsEngine;
+use com\github\mustache\InMemory;
 
 abstract class HelperTest extends \unittest\TestCase {
+  protected $templates;
+
+  /** @return void */
+  public function setUp() {
+    $this->templates= new InMemory();
+  }
 
   /**
    * Evaluate a string template against given variables and return the output.
@@ -12,6 +19,6 @@ abstract class HelperTest extends \unittest\TestCase {
    * @return string
    */
   protected function evaluate($template, $variables) {
-    return (new HandlebarsEngine())->render($template, $variables);
+    return (new HandlebarsEngine())->withTemplates($this->templates)->render($template, $variables);
   }
 }

src/test/php/com/handlebarsjs/unittest/InlinePartialHelperTest.class.php

@@ -0,0 +1,10 @@
+<?php namespace com\handlebarsjs\unittest;
+
+class InlinePartialHelperTest extends HelperTest {
+
+  #[@test]
+  public function basic_usage() {
+    $template= '{{#*inline "myPartial"}}My Content{{/inline}}{{#each children}}{{> myPartial}} {{/each}}';
+    $this->assertEquals('My Content My Content My Content ', $this->evaluate($template, ['children' => [1, 2, 3]]));
+  }
+}

src/test/php/com/handlebarsjs/unittest/ParsingTest.class.php

@@ -7,7 +7,10 @@
 use com\handlebarsjs\Quoted;
 use com\handlebarsjs\Constant;
 use com\handlebarsjs\Expression;
+use com\handlebarsjs\PartialBlockHelper;
+use com\handlebarsjs\InlinePartialHelper;
 use com\github\mustache\NodeList;
+use com\github\mustache\TextNode;
 use com\github\mustache\VariableNode;
 use com\github\mustache\TemplateFormatException;
 use text\StringTokenizer;
@@ -100,6 +103,26 @@ public function dynamic_partial_with_context() {
     );
   }
 
+  #[@test]
+  public function partial_block() {
+    $this->assertEquals(
+      new NodeList([new PartialBlockHelper(['layout'], new NodeList([
+        new TextNode('Content')
+      ]))]),
+      $this->parse('{{#> layout}}Content{{/layout}}')
+    );
+  }
+
+  #[@test]
+  public function inline_partial() {
+    $this->assertEquals(
+      new NodeList([new InlinePartialHelper([new Quoted('myPartial')], new NodeList([
+        new TextNode('Content')
+      ]))]),
+      $this->parse('{{#*inline "myPartial"}}Content{{/inline}}')
+    );
+  }
+
   #[@test, @expect(class= TemplateFormatException::class, withMessage= '/Illegal nesting/')]
   public function incorrect_ending_tag() {
     $this->parse('{{#each users}}...{{/each users}}');

src/test/php/com/handlebarsjs/unittest/PartialBlockHelperTest.class.php

@@ -0,0 +1,21 @@
+<?php namespace com\handlebarsjs\unittest;
+
+class PartialBlockHelperTest extends HelperTest {
+
+  #[@test]
+  public function existing_partial() {
+    $this->templates->add('layout', 'My layout');
+    $this->assertEquals('My layout', $this->evaluate('{{#> layout}}My content{{/layout}}', []));
+  }
+
+  #[@test]
+  public function existing_partial_with_partial_block() {
+    $this->templates->add('layout', 'My layout {{> @partial-block }}');
+    $this->assertEquals('My layout My content', $this->evaluate('{{#> layout}}My content{{/layout}}', []));
+  }
+
+  #[@test]
+  public function non_existant_partial_renders_default() {
+    $this->assertEquals('My content', $this->evaluate('{{#> layout}}My content{{/layout}}', []));
+  }
+}