Use Blade::directive instead of Blade::extend (#237)

* Add blade directives; Remove use of require_once

* Update README for renamed lm_attrs

* Use constants correctly

* Update @lm_attrs syntax in examples

* Add deprecation warning

README.md

@@ -62,7 +62,7 @@ __For Laravel 4.x, check [version 1.5.0](https://github.com/lavary/laravel-menu/
 * [Advanced Usage](#advanced-usage)
     + [A Basic Example](#a-basic-example)
     + [Control Structure for Blade](#control-structure-for-blade)
-        - [@lm-attrs](#lm-attrs)
+        - [@lm_attrs](#lm_attrs)
     + [Attributes and Callback function of item](#attributes-and-callback-function-of-item)
 * [Configuration](#configuration)
 * [If You Need Help](#if-you-need-help)
@@ -1472,7 +1472,7 @@ To put the rendered menu in your application template, you can simply include `c
 
 Laravel menu extends Blade to handle special layouts.
 
-##### @lm-attrs
+##### @lm_attrs
 
 You might encounter situations when some of your HTML properties are explicitly written inside your view instead of dynamically being defined when adding the item; However you will need to merge these static attributes with your Item's attributes.
 
@@ -1501,7 +1501,7 @@ The view:
 
 ```php
 @foreach($items as $item)
-  <li@lm-attrs($item) @if($item->hasChildren()) class="dropdown" @endif data-test="test" @lm-endattrs>
+  <li @lm_attrs($item) @if($item->hasChildren()) class="dropdown" @endif data-test="test" @lm_endattrs>
       <a href="{!! $item->url !!}">{!! $item->title !!} </a>
       @if($item->hasChildren())
         <ul class="dropdown-menu">

src/Lavary/Menu/ServiceProvider.php

@@ -3,6 +3,7 @@
 namespace Lavary\Menu;
 
 use Illuminate\Support\ServiceProvider as BaseServiceProvider;
+use Illuminate\Support\Facades\Blade;
 
 class ServiceProvider extends BaseServiceProvider
 {
@@ -26,13 +27,68 @@ public function register()
         });
     }
 
+    // Patterns and Replace string for lm-attr
+    // Remove with next major version
+    const LM_ATTRS_PATTERN = '/(\s*)@lm-attrs\s*\((\$[^)]+)\)/';
+    const LM_ATTRS_REPLACE = '$1<?php $lm_attrs = $2->attr(); ob_start(); ?>';
+
+    // Patterns and Replace string for lm-endattr
+    // Remove with next major version
+    const LM_ENDATTRS_PATTERN = '/(?<!\w)(\s*)@lm-endattrs(\s*)/';
+    const LM_ENDATTRS_REPLACE = '$1<?php echo \Lavary\Menu\Builder::mergeStatic(ob_get_clean(), $lm_attrs); ?>$2';
+
+    /*
+     * Extending Blade engine. Remove with next major version
+     *
+     * @deprecated
+     * @return void
+     */
+    protected function bladeExtensions()
+    {
+        Blade::extend(function ($view, $compiler) {
+            if (preg_match(self::LM_ATTRS_PATTERN, $view)) {
+              \Log::debug("laravel-menu: @lm-attrs/@lm-endattrs is deprecated. Please switch to @lm_attrs and @lm_endattrs");
+            }
+            return preg_replace(self::LM_ATTRS_PATTERN, self::LM_ATTRS_REPLACE, $view);
+        });
+
+        Blade::extend(function ($view, $compiler) {
+            return preg_replace(self::LM_ENDATTRS_PATTERN, self::LM_ENDATTRS_REPLACE, $view);
+        });
+    }
+
+    /*
+     * Adding custom Blade directives.
+     */
+    protected function bladeDirectives()
+    {
+        /*
+         * Buffers the output if there's any.
+         * The output will be passed to mergeStatic()
+         * where it is merged with item's attributes
+         */
+        Blade::directive('lm_attrs', function ($expression) {
+            return '<?php $lm_attrs = ' . $expression . '->attr(); ob_start(); ?>';
+        });
+
+        /*
+         * Reads the buffer data using ob_get_clean()
+         * and passes it to MergeStatic().
+         * mergeStatic() takes the static string,
+         * converts it into a normal array and merges it with others.
+         */
+        Blade::directive('lm_endattrs', function ($expression) {
+            return '<?php echo \Lavary\Menu\Builder::mergeStatic(ob_get_clean(), $lm_attrs); ?>';
+        });
+    }
+
     /**
      * Bootstrap the application events.
      */
     public function boot()
     {
-        // Extending Blade engine
-        require_once 'blade/lm-attrs.php';
+        $this->bladeDirectives();
+        $this->bladeExtensions();
 
         $this->loadViewsFrom(__DIR__.'/resources/views', 'laravel-menu');
 

src/Lavary/Menu/resources/views/bootstrap-navbar-items.blade.php

@@ -1,5 +1,5 @@
 @foreach($items as $item)
-  <li@lm-attrs($item) @if($item->hasChildren()) class="nav-item dropdown" @endif @lm-endattrs>
+  <li @lm_attrs($item) @if($item->hasChildren()) class="nav-item dropdown" @endif @lm_endattrs>
     @if($item->link) <a@lm-attrs($item->link) @if($item->hasChildren()) class="nav-link dropdown-toggle" role="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false" @else class="nav-link" @endif @lm-endattrs href="{!! $item->url() !!}">
       {!! $item->title !!}
       @if($item->hasChildren()) <b class="caret"></b> @endif
@@ -9,9 +9,9 @@
     @endif
     @if($item->hasChildren())
       <ul class="dropdown-menu">
-        @include(config('laravel-menu.views.bootstrap-items'), 
+        @include(config('laravel-menu.views.bootstrap-items'),
 array('items' => $item->children()))
-      </ul> 
+      </ul>
     @endif
   </li>
   @if($item->divider)