Add test for invalid license

tests/phpunit/testdata/plugins/test-plugin-plugin-readme-errors-invalid-license/load.php

@@ -0,0 +1,15 @@
+<?php
+/**
+ * Plugin Name: Test Plugin Readme Errors (invalid license)
+ * 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: Oculus VR Inc. Software Development Kit License
+ * Text Domain: test-plugin-check-errors-invalid-license
+ *
+ * @package test-plugin-check-errors-invalid-license
+ */

tests/phpunit/testdata/plugins/test-plugin-plugin-readme-errors-invalid-license/readme.txt

@@ -0,0 +1,11 @@
+=== Test Plugin with readme ===
+
+Contributors:      plugin-check
+Requires at least: 6.0
+Tested up to:      6.6
+Requires PHP:      5.6
+Stable tag:        1.0.0
+Tags:              testing, security
+License:           Oculus VR Inc. Software Development Kit License
+
+Plugin description.

tests/phpunit/tests/Checker/Checks/Plugin_Header_Fields_Check_Tests.php

@@ -87,4 +87,19 @@ public function test_run_with_errors_mismatched_license() {
 
 		$this->assertCount( 1, wp_list_filter( $warnings['load.php'][0][0], array( 'code' => 'license_mismatch' ) ) );
 	}
+
+	public function test_run_with_errors_invalid_license() {
+		$check         = new Plugin_Header_Fields_Check();
+		$check_context = new Check_Context( UNIT_TESTS_PLUGIN_DIR . 'test-plugin-plugin-readme-errors-invalid-license/load.php' );
+		$check_result  = new Check_Result( $check_context );
+
+		$check->run( $check_result );
+
+		$errors = $check_result->get_errors();
+
+		$this->assertNotEmpty( $errors );
+		$this->assertArrayHasKey( 'load.php', $errors );
+
+		$this->assertCount( 1, wp_list_filter( $errors['load.php'][0][0], array( 'code' => 'plugin_header_invalid_license' ) ) );
+	}
 }

tests/phpunit/tests/Checker/Checks/Plugin_Readme_Check_Tests.php

@@ -177,6 +177,21 @@ public function test_run_with_errors_no_license() {
 		$this->assertCount( 1, wp_list_filter( $errors['readme.txt'][0][0], array( 'code' => 'no_license' ) ) );
 	}
 
+	public function test_run_with_errors_invalid_license() {
+		$readme_check         = new Plugin_Readme_Check();
+		$check_context = new Check_Context( UNIT_TESTS_PLUGIN_DIR . 'test-plugin-plugin-readme-errors-invalid-license/load.php' );
+		$check_result  = new Check_Result( $check_context );
+
+		$readme_check->run( $check_result );
+
+		$warnings = $check_result->get_warnings();
+
+		$this->assertNotEmpty( $warnings );
+		$this->assertArrayHasKey( 'readme.txt', $warnings );
+
+		$this->assertCount( 1, wp_list_filter( $warnings['readme.txt'][0][0], array( 'code' => 'invalid_license' ) ) );
+	}
+
 	public function test_run_with_errors_tested_upto() {
 		$readme_check  = new Plugin_Readme_Check();
 		$check_context = new Check_Context( UNIT_TESTS_PLUGIN_DIR . 'test-plugin-plugin-readme-errors-tested-upto/load.php' );