Complete PHPUnit infrastructure for out-of-the-box local and CI testing, including initial tests

.github/workflows/php-test.yml

@@ -0,0 +1,54 @@
+name: Unit Testing
+
+on:
+  push:
+    branches:
+      - trunk
+    # Only run if PHP-related files changed.
+    paths:
+      - '.github/workflows/php-test.yml'
+      - '**.php'
+      - 'phpunit.xml.dist'
+      - 'tests/multisite.xml'
+      - 'composer.json'
+      - 'composer.lock'
+  pull_request:
+    branches:
+      - trunk
+    # Only run if PHP-related files changed.
+    paths:
+      - '.github/workflows/php-test.yml'
+      - '**.php'
+      - 'phpunit.xml.dist'
+      - 'tests/multisite.xml'
+      - 'composer.json'
+      - 'composer.lock'
+    types:
+      - opened
+      - reopened
+      - synchronize
+
+jobs:
+  php-test:
+    name: PHP
+    runs-on: ubuntu-latest
+    timeout-minutes: 20
+    steps:
+      - uses: styfle/cancel-workflow-action@0.8.0
+      - uses: actions/checkout@v2
+      - name: Read .nvmrc
+        run: echo "##[set-output name=NVMRC;]$(cat .nvmrc)"
+        id: nvm
+      - name: Setup Node.js (.nvmrc)
+        uses: actions/setup-node@v1
+        with:
+          node-version: '${{ steps.nvm.outputs.NVMRC }}'
+          cache: npm
+      - name: npm install
+        run: npm ci
+      - name: Install WordPress
+        run: npm run wp-env start
+      - name: Running single site unit tests
+        run: npm run test-php
+      - name: Running multisite unit tests
+        run: npm run test-php-multisite

.nvmrc

@@ -0,0 +1 @@
+14

.wp-env.json

@@ -0,0 +1,4 @@
+{
+	"core": null,
+	"plugins": [ "." ]
+}

README.md

@@ -2,4 +2,18 @@
 
 Monorepo for the [WordPress Performance Group](https://make.wordpress.org/core/tag/performance/), primarily for the overall performance plugin, which is a collection of standalone performance modules.
 
+## Useful commands
+
+In order to run the following commands, you need to have [Node.js](https://nodejs.org) (including `npm`) and [Docker](https://www.docker.com) installed, and Docker needs to be up and running. The Docker configuration used relies on the [`@wordpress/env` package](https://developer.wordpress.org/block-editor/reference-guides/packages/packages-env/).
+
+* `npm install`: Installs local development dependencies.
+* `npm run wp-env start`: Starts the local development environment.
+* `npm run wp-env stop`: Stops the local development environment.
+* `npm run lint-php`: Lints all PHP code.
+* `npm run format-php`: Formats all PHP code.
+* `npm run test-php`: Runs PHPUnit tests for all PHP code.
+* `npm run test-php-multisite`: Runs PHPUnit tests in multisite for all PHP code.
+
+## Documentation
+
 [See the `/docs` folder for documentation.](https://github.com/WordPress/performance/blob/trunk/docs/README.md)

composer.json

@@ -1,30 +1,32 @@
 {
-	"name": "wordpress/performance",
-	"type": "wordpress-plugin",
-	"license": "GPL-2.0-or-later",
-	"description": "Performance plugin from the WordPress Performance Group, which is a collection of standalone performance modules.",
-	"homepage": "https://wordpress.org/plugins/performance-lab/",
-	"keywords": [
-		"performance",
-		"wordpress"
-	],
-	"support": {
-		"issues": "https://github.com/WordPress/performance/issues"
-	},
-	"require-dev": {
-		"dealerdirect/phpcodesniffer-composer-installer": "^0.7",
-		"phpcompatibility/php-compatibility": "^9.3",
-		"phpunit/phpunit": "^8.5",
-		"squizlabs/php_codesniffer": "^3.5",
-		"wp-coding-standards/wpcs": "^2.2",
-		"wp-phpunit/wp-phpunit": "^5.8"
-	},
-	"require": {
-		"composer/installers": "~1.0"
-	},
-	"scripts": {
-		"format": "phpcbf --standard=phpcs.xml.dist --report-summary --report-source",
-		"lint": "phpcs --standard=phpcs.xml.dist",
-		"test": "phpunit"
-	}
+  "name": "wordpress/performance",
+  "type": "wordpress-plugin",
+  "license": "GPL-2.0-or-later",
+  "description": "Performance plugin from the WordPress Performance Group, which is a collection of standalone performance modules.",
+  "homepage": "https://wordpress.org/plugins/performance-lab/",
+  "keywords": [
+    "performance",
+    "wordpress"
+  ],
+  "support": {
+    "issues": "https://github.com/WordPress/performance/issues"
+  },
+  "require-dev": {
+    "dealerdirect/phpcodesniffer-composer-installer": "^0.7",
+    "phpcompatibility/php-compatibility": "^9.3",
+    "phpunit/phpunit": "^8.5",
+    "squizlabs/php_codesniffer": "^3.5",
+    "wp-coding-standards/wpcs": "^2.2",
+    "wp-phpunit/wp-phpunit": "^5.8",
+    "yoast/phpunit-polyfills": "^1.0"
+  },
+  "require": {
+    "composer/installers": "~1.0"
+  },
+  "scripts": {
+    "format": "phpcbf --standard=phpcs.xml.dist --report-summary --report-source",
+    "lint": "phpcs --standard=phpcs.xml.dist",
+    "test": "phpunit -c phpunit.xml.dist --verbose",
+    "test-multisite": "WP_MULTISITE=1 phpunit -c tests/multisite.xml --verbose"
+  }
 }

load.php

@@ -43,12 +43,25 @@ function perflab_register_modules_setting() {
  * @return array Sanitized modules setting value.
  */
 function perflab_sanitize_modules_setting( $value ) {
-	// TODO: Make this more error-proof.
 	if ( ! is_array( $value ) ) {
 		return array();
 	}
 
-	return $value;
+	// Ensure that every element is an array with an 'enabled' key.
+	return array_filter(
+		array_map(
+			function( $module_settings ) {
+				if ( ! is_array( $module_settings ) ) {
+					return array();
+				}
+				return array_merge(
+					array( 'enabled' => false ),
+					$module_settings
+				);
+			},
+			$value
+		)
+	);
 }
 
 /**