Modify Plugin Checker to only check root directory readme files

includes/Checker/Checks/Plugin_Readme_Check.php

@@ -42,8 +42,41 @@ public function get_categories() {
 	 * @param array        $files  Array of plugin files.
 	 */
 	protected function check_files( Check_Result $result, array $files ) {
+
+		$plugin_relative_path = $result->plugin()->path();
+
 		// Find the readme file.
-		$readme = self::filter_files_by_regex( $files, '/readme\.(txt|md)$/i' );
+		$readme_list = self::filter_files_by_regex( $files, '/readme\.(txt|md)$/i' );
+
+		// Filter the readme files that located at rootx.
+		$potential_readme_files = array_filter(
+			$readme_list,
+			function ( $file ) use ( $plugin_relative_path ) {
+				$file = str_replace( $plugin_relative_path, '', $file );
+				if ( ! strpos( $file, '/' ) ) {
+					return true;
+				}
+			}
+		);
+
+		// Find the .txt versions of the readme files.
+		$readme_txt = array_filter(
+			$potential_readme_files,
+			function ( $file ) {
+				return preg_match( '/^readme\.txt$/i', basename( $file ) );
+			}
+		);
+
+		// Find the .md versions of the readme files.
+		$readme_md = array_filter(
+			$potential_readme_files,
+			function ( $file ) {
+				return preg_match( '/^readme\.md$/i', basename( $file ) );
+			}
+		);
+
+		// If there's a .txt version, ignore .md versions.
+		$readme = ( ! empty( $readme_txt ) ) ? $readme_txt : $readme_md;
 
 		// If the readme file does not exist, add a warning and skip other tests.
 		if ( empty( $readme ) ) {
@@ -84,24 +117,20 @@ private function check_default_text( Check_Result $result, array $files ) {
 			'Donate link: http://example.com/',
 		);
 
-		$file = '';
 		foreach ( $default_text_patterns as $pattern ) {
 			$file = self::file_str_contains( $files, $pattern );
 			if ( $file ) {
+				$result->add_message(
+					false,
+					__( 'The readme appears to contain default text.', 'plugin-check' ),
+					array(
+						'code' => 'default_readme_text',
+						'file' => str_replace( $result->plugin()->path(), '', $file ),
+					)
+				);
 				break;
 			}
 		}
-
-		if ( $file ) {
-			$result->add_message(
-				false,
-				__( 'The readme appears to contain default text.', 'plugin-check' ),
-				array(
-					'code' => 'default_readme_text',
-					'file' => str_replace( $result->plugin()->path(), '', $file ),
-				)
-			);
-		}
 	}
 
 	/**

tests/phpunit/Checker/Checks/Plugin_Readme_Check_Tests.php

@@ -166,4 +166,20 @@ public function test_run_md_with_errors() {
 		$this->assertArrayHasKey( 'code', $warnings['readme.md'][0][0][3] );
 		$this->assertEquals( 'stable_tag_mismatch', $warnings['readme.md'][0][0][3]['code'] );
 	}
+
+	public function test_run_root_readme_file_without_errors() {
+		$readme_check  = new Plugin_Readme_Check();
+		$check_context = new Check_Context( UNIT_TESTS_PLUGIN_DIR . 'test-plugin-root-readme-without-errors/load.php' );
+		$check_result  = new Check_Result( $check_context );
+
+		$readme_check->run( $check_result );
+
+		$errors   = $check_result->get_errors();
+		$warnings = $check_result->get_warnings();
+
+		$this->assertEmpty( $errors );
+		$this->assertEmpty( $warnings );
+		$this->assertEquals( 0, $check_result->get_error_count() );
+		$this->assertEquals( 0, $check_result->get_warning_count() );
+	}
 }

tests/phpunit/testdata/plugins/test-plugin-plugin-readme-without-errors/readme.md

@@ -0,0 +1,13 @@
+
+=== Plugin Check ===
+
+Contributors:      wordpressdotorg
+Requires at least: 6.0
+Tested up to:      6.1
+Requires PHP:      5.6
+Stable tag:        trunk
+License:           Oculus VR Inc. Software Development Kit License
+License URI:       https://www.gnu.org/licenses/gpl-2.0.html
+Tags:              performance, testing, security
+
+Here is a short description of the plugin.

tests/phpunit/testdata/plugins/test-plugin-root-readme-without-errors/load.php

@@ -0,0 +1,16 @@
+<?php
+/**
+ * Plugin Name: Test Plugin Readme check (no errors)
+ * Plugin URI: https://github.com/wordpress/plugin-check
+ * Description: Test plugin for the Readme check.
+ * Requires at least: 6.0
+ * Requires PHP: 5.6
+ * Version: 1.0.0
+ * Author: WordPress Performance Team
+ * Author URI: https://make.wordpress.org/performance/
+ * License: GPLv2 or later
+ * License URI: https://www.gnu.org/licenses/old-licenses/gpl-2.0.html
+ * Text Domain: test-plugin-check-errors
+ *
+ * @package test-plugin-check-errors
+ */

tests/phpunit/testdata/plugins/test-plugin-root-readme-without-errors/readme.txt

@@ -0,0 +1,13 @@
+
+=== Test Plugin with readme ===
+
+Contributors:      plugin-check
+Requires at least: 6.0
+Tested up to:      6.1
+Requires PHP:      5.6
+Stable tag:        1.0.0
+License:           GPLv2 or later
+License URI:       https://www.gnu.org/licenses/gpl-2.0.html
+Tags:              testing, security
+
+A simple readme file for testing.

tests/phpunit/testdata/plugins/test-plugin-root-readme-without-errors/sub-directory/readme.txt

@@ -0,0 +1,14 @@
+
+=== Test Plugin with readme ===
+
+Contributors:      plugin-check
+Requires at least: 6.0
+Tested up to:      6.1
+Requires PHP:      5.6
+Stable tag:        n.e.x.t
+License:           GPLv2 or later
+License URI:       https://www.gnu.org/licenses/gpl-2.0.html
+Donate URL:        https://example.com
+Tags:              tag1, testing, security
+
+Here is a short description of the plugin.