Files containing exclusively non-relevant code are ok

As far as all the non-relevant code (namespace, uses, declare and
defines) is also code without side effects, these files don't need
the MOODLE_INTERNAL check).

Covered with tests.

This needs to be merged after #190.

Fixes #188

phpcs/moodle/Sniffs/Files/MoodleInternalSniff.php

@@ -80,6 +80,10 @@ public function process(File $file, $pointer) {
 
         // Find where real code is and check from there.
         $pointer = $this->get_position_of_relevant_code($file, $pointer);
+        if (!$pointer) {
+            // The file only contains non-relevant (and non side-effects) code. We are done.
+            return;
+        }
 
         if ($this->is_config_php_incluson($file, $pointer)) {
             // We are requiring config.php. This file is good, hurrah!
@@ -136,8 +140,8 @@ public function process(File $file, $pointer) {
     }
 
     /**
-     * Finds the position of the first bit of relevant code (ignoring namespaces
-     * and define statements).
+     * Finds the position of the first bit of relevant code (ignoring namespaces,
+     * uses, declares and define statements).
      *
      * @param File $file The file being scanned.
      * @param int $pointer The position in the stack.

phpcs/moodle/tests/files_moodleinternal_test.php

@@ -168,8 +168,20 @@ public function test_moodle_files_moodleinternal_old_style_if_die() {
         $this->verify_cs_results();
     }
 
+    public function test_moodle_files_moodleinternal_no_relevant_ok() {
+        // Files that only contain non-relevant (and no side-effects) code.
+        $this->set_standard('moodle');
+        $this->set_sniff('moodle.Files.MoodleInternal');
+        $this->set_fixture(__DIR__ . '/fixtures/files/moodleinternal/no_relevant_ok.php');
+
+        $this->set_errors([]);
+        $this->set_warnings([]);
+
+        $this->verify_cs_results();
+    }
+
     public function test_moodle_files_moodleinternal_unexpected() {
-        // Old style if statement MOODLE_INTERNAL check.
+        // Unexpected (not needed) check.
         $this->set_standard('moodle');
         $this->set_sniff('moodle.Files.MoodleInternal');
         $this->set_fixture(__DIR__ . '/fixtures/files/moodleinternal/unexpected.php');

phpcs/moodle/tests/fixtures/files/moodleinternal/no_relevant_ok.php

@@ -0,0 +1,32 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * A file that only contains non-relevant (and no side effects) code.
+ */
+
+declare(strict_types=1);
+declare(encoding='UTF-8');
+declare(ticks=1);
+
+namespace local_codechecker;;
+
+use something;
+use various, things;
+use something as elsething;
+
+define('ONE', 1);
+define('TWO', 2);