Define target platform in composer.json and fix .travis.yml

.travis.yml

@@ -13,20 +13,25 @@ matrix:
     - php: nightly
   fast_finish: true
 
-install:
-  # --ignore-platform-reqs, because https://github.com/FriendsOfPHP/PHP-CS-Fixer/pull/2722
-  - composer update -n --prefer-dist --ignore-platform-reqs
+env:
+  - AMP_DEBUG=true
 
+before_install:
+  - phpenv config-rm xdebug.ini || echo "No xdebug config."
+
+install:
   - travis/install-eio.sh
   - travis/install-uv.sh
+  - composer update -n --prefer-dist
+  - wget https://github.com/php-coveralls/php-coveralls/releases/download/v1.0.2/coveralls.phar
+  - chmod +x coveralls.phar
 
 script:
   - phpdbg -qrr vendor/bin/phpunit --coverage-text --coverage-clover build/logs/clover.xml
   - PHP_CS_FIXER_IGNORE_ENV=1 php vendor/bin/php-cs-fixer --diff --dry-run -v fix
 
 after_script:
-  - composer require php-coveralls/php-coveralls ^1.0.2 --ignore-platform-reqs
-  - php vendor/bin/coveralls -v
+  - ./coveralls.phar
 
 cache:
   directories:

composer.json

@@ -51,5 +51,10 @@
         "psr-4": {
             "Amp\\File\\Test\\": "test"
         }
+    },
+    "config": {
+        "platform": {
+            "php": "7.0.0"
+        }
     }
 }