Update file .travis.yml

Author: MiniModel

.travis.yml

@@ -1,6 +1,14 @@
+dist: xenial
+
+addons:
+  apt:
+    packages:
+      - ant-optional
+
 language: php
 
 php:
+  - "7.3"
   - "7.2"
   - "7.1"
   - "7.0"
@@ -9,18 +17,31 @@ php:
 env:
   - CONTAO_VERSION=~3.5.5
 
-sudo: false
-
-before_install:
-  - echo "memory_limit = -1" > travis.php.ini && phpenv config-add travis.php.ini
-
-install:
+before_script:
+  - echo "memory_limit=-1" >> ~/.phpenv/versions/$(phpenv version-name)/etc/conf.d/travis.ini
   - travis_retry composer self-update && composer --version
   - travis_retry composer require contao/core $CONTAO_VERSION --no-update
+  - >
+    if [ "x${TRAVIS_TAG}" != "x" ]; then
+      export COMPOSER_ROOT_VERSION=${TRAVIS_TAG}
+    else
+      export COMPOSER_ROOT_VERSION=$([[ ${TRAVIS_BRANCH} =~ hotfix/([0-9.]*(-(alpha|beta|rc)[0-9]+)?) ]] \
+        && echo ${BASH_REMATCH[1]} \
+        || echo dev-${TRAVIS_BRANCH})
+    fi
+  - echo "Using root version ${COMPOSER_ROOT_VERSION}"
   - travis_retry composer update --prefer-dist --no-interaction
 
 script: ant -keep-going
 
 # Hack to make things work again - we can not use a shallow repository.
 git:
   depth: 2147483647
+
+branches:
+  except:
+    - /.*-translation/
+
+cache:
+  directories:
+    - vendor