Remove format and broken generateJsonHelper (#1053)

The JSON generate doesn't work, always generates an empty list.

I looked a bit around and seems changes around 3 years ago broke it.

Since there was no bug report ever about this, I conclude this feature
isn't used and suggest to remove it.

This also changes the config `filename` as there's no need for the
extension-less version and the format is gone too. This change is
backwards compatible as we just add back the `.php` in case it's missing
though users are encouraged to update it.

src/Generator.php

@@ -67,21 +67,9 @@ class Generator
     /**
      * Generate the helper file contents;
      *
-     * @param  string  $format  The format to generate the helper in (php/json)
      * @return string;
      */
-    public function generate($format = 'php')
-    {
-        // Check if the generator for this format exists
-        $method = 'generate' . ucfirst($format) . 'Helper';
-        if (method_exists($this, $method)) {
-            return $this->$method();
-        }
-
-        return $this->generatePhpHelper();
-    }
-
-    public function generatePhpHelper()
+    public function generate()
     {
         $app = app();
         return $this->view->make('helper')
@@ -94,33 +82,6 @@ class Generator
             ->render();
     }
 
-    public function generateJsonHelper()
-    {
-        $classes = [];
-        foreach ($this->getValidAliases() as $aliases) {
-            foreach ($aliases as $alias) {
-                $functions = [];
-                foreach ($alias->getMethods() as $method) {
-                    $functions[$method->getName()] = '(' . $method->getParamsWithDefault() . ')';
-                }
-                $classes[$alias->getAlias()] = [
-                    'functions' => $functions,
-                ];
-            }
-        }
-
-        $flags = JSON_FORCE_OBJECT;
-        if (defined('JSON_PRETTY_PRINT')) {
-            $flags |= JSON_PRETTY_PRINT;
-        }
-
-        return json_encode([
-            'php' => [
-                'classes' => $classes,
-            ],
-        ], $flags);
-    }
-
     protected function detectDrivers()
     {
         $defaultUserModel = config('auth.providers.users.model', config('auth.model', 'App\User'));