fix: handle invalid package uploads

tests/Unit/Admin/DashboardTemplateTest.php

@@ -0,0 +1,41 @@
+<?php
+
+namespace WPContentSync\Tests\Unit\Admin;
+
+use PHPUnit\Framework\TestCase;
+use WPContentSync\Settings\Settings;
+
+class DashboardTemplateTest extends TestCase {
+	protected function tearDown(): void {
+		$_GET = array();
+
+		parent::tearDown();
+	}
+
+	public function test_it_renders_import_error_notices(): void {
+		$_GET['wpcs_import_error'] = 'The selected file is not valid JSON.';
+
+		$output = $this->renderDashboard();
+
+		self::assertStringContainsString( 'notice-error', $output );
+		self::assertStringContainsString( 'The selected file is not valid JSON.', $output );
+	}
+
+	public function test_it_renders_import_success_notices(): void {
+		$_GET['wpcs_imported'] = '1';
+
+		$output = $this->renderDashboard();
+
+		self::assertStringContainsString( 'notice-success', $output );
+		self::assertStringContainsString( 'The package JSON file was validated successfully.', $output );
+	}
+
+	private function renderDashboard(): string {
+		$settings = Settings::fromArray( array() );
+
+		ob_start();
+		include WPCS_PLUGIN_DIR . 'templates/admin/dashboard.php';
+
+		return (string) ob_get_clean();
+	}
+}