Update Travis builds to include PHP 7, update PHPUnit to 5.7

.travis.yml

@@ -1,34 +1,25 @@
-# See https://github.com/silverstripe-labs/silverstripe-travis-support for setup details
+# See https://github.com/silverstripe/silverstripe-travis-support for setup details
-
-sudo: false
 
 language: php
 
-dist: precise
+dist: trusty
-
-php:
-  - 5.4
-  - 5.5
-  - 5.6
-
-env:
-  - DB=MYSQL CORE_RELEASE=3.2
 
 matrix:
   include:
-    - php: 5.6
+    - php: '5.6'
-      env: DB=MYSQL CORE_RELEASE=3
+      env: DB=MYSQL CORE_RELEASE=3.6
-    - php: 5.6
+    - php: '7.0'
-      env: DB=PGSQL CORE_RELEASE=3.1
+      env: DB=PGSQL CORE_RELEASE=3.7
-    - php: 5.6
+    - php: '7.1'
-      env: DB=PGSQL CORE_RELEASE=3.3
+      env: DB=MYSQL CORE_RELEASE=3.7
-    - php: 5.6
+    - php: '7.2'
-      env: DB=PGSQL CORE_RELEASE=3.4
+      env: DB=MYSQL CORE_RELEASE=3.7
-  fast_finish: true
+    - php: '7.3'
+      env: DB=MYSQL CORE_RELEASE=3.7
 
 before_script:
   - composer self-update || true
-  - git clone git://github.com/silverstripe-labs/silverstripe-travis-support.git ~/travis-support
+  - git clone git://github.com/silverstripe/silverstripe-travis-support.git ~/travis-support
   - php ~/travis-support/travis_setup.php --source `pwd` --target ~/builds/ss
   - cd ~/builds/ss
   - composer install

composer.json

@@ -21,6 +21,9 @@
 	"require": {
 		"silverstripe/framework": "~3.1"
 	},
+	"require-dev": {
+		"phpunit/phpunit": "^5.7"
+	},
 	"extra": {
 		"installer-name": "gridfieldextensions",
 		"screenshots": [