Update test suite to use WP-CLI v2

.travis.yml

@@ -2,6 +2,7 @@ sudo: false
 dist: trusty
 
 language: php
+php: 7.2
 
 notifications:
   email:
@@ -21,19 +22,6 @@ env:
     - PATH="$TRAVIS_BUILD_DIR/vendor/bin:$PATH"
     - WP_CLI_BIN_DIR="$TRAVIS_BUILD_DIR/vendor/bin"
 
-matrix:
-  include:
-    - php: 7.2
-      env: WP_VERSION=latest
-    - php: 7.1
-      env: WP_VERSION=latest
-    - php: 7.0
-      env: WP_VERSION=latest
-    - php: 5.6
-      env: WP_VERSION=latest
-    - php: 5.6
-      env: WP_VERSION=3.7.11
-
 before_install:
   - |
     # Remove Xdebug for a huge performance increase:
@@ -45,14 +33,38 @@ before_install:
   - |
     # Raise PHP memory limit to 2048MB
     echo 'memory_limit = 2048M' >> ~/.phpenv/versions/$(phpenv version-name)/etc/conf.d/travis.ini
+  - composer validate
 
 install:
-  - composer require wp-cli/wp-cli:dev-master
   - composer install
-  - bash bin/install-package-tests.sh
-
-before_script:
-  - composer validate
+  - composer prepare-tests
 
 script:
-  - bash bin/test.sh
+  - composer phpunit
+  - composer behat
+
+jobs:
+  include:
+    - stage: sniff
+      script:
+        # - composer lint
+        - composer phpcs
+      env: BUILD=sniff
+    - stage: test
+      php: 7.2
+      env: WP_VERSION=latest
+    - stage: test
+      php: 7.1
+      env: WP_VERSION=latest
+    - stage: test
+      php: 7.0
+      env: WP_VERSION=latest
+    - stage: test
+      php: 5.6
+      env: WP_VERSION=latest
+    - stage: test
+      php: 5.6
+      env: WP_VERSION=3.7.11
+    - stage: test
+      php: 5.4
+      env: WP_VERSION=latest

composer.json

@@ -14,10 +14,27 @@
         "files": [ "command.php" ]
     },
     "require": {
-        "wp-cli/wp-cli": "^1.1.0"
+        "wp-cli/wp-cli": "^2"
     },
     "require-dev": {
-        "behat/behat": "~2.5"
+        "behat/behat": "~2.5",
+        "wp-cli/wp-cli-tests": "^2",
+        "wp-cli/extension-command": "^2",
+        "wp-cli/core-command": "^2",
+        "wp-cli/checksum-command": "^2"
+    },
+    "scripts": {
+      "lint": "run-linter-tests",
+      "phpcs": "run-phpcs-tests",
+      "phpunit": "run-php-unit-tests",
+      "behat": "run-behat-tests",
+      "prepare-tests": "install-package-tests",
+      "test": [
+          "@lint",
+          "@phpcs",
+          "@phpunit",
+          "@behat"
+      ]
     },
     "extra": {
         "commands": [ "reinstall" ]