Add PHPUnit to require-dev and support legacy PHP 5.3 through PHP 7.2 and HHVM

.travis.yml

@@ -1,19 +1,30 @@
 language: php
 
 php:
-  - 5.3
+# - 5.3 # requires old distro, see below
+  - 5.4
+  - 5.5
   - 5.6
-  - 7
-  - hhvm
+  - 7.0
+  - 7.1
+  - 7.2
+  - 7.3
+  - hhvm # ignore errors, see below
+
+# lock distro so future defaults will not break the build
+dist: trusty
 
 matrix:
+  include:
+    - php: 5.3
+      dist: precise
   allow_failures:
-    - php: 7
     - php: hhvm
 
+sudo: false
+
 install:
-  - composer install --prefer-source --no-interaction
+  - composer install --no-interaction
 
 script:
-  - phpunit --coverage-text
-
+  - vendor/bin/phpunit --coverage-text

README.md

@@ -23,6 +23,7 @@ for your project among with its bundled dependencies.
     * [Updating dependency](#updating-dependency)
   * [Manual Installation from Source](#manual-installation-from-source)
     * [Updating manually](#updating-manually)
+* [Tests](#tests)
 * [License](#license)
 
 ## Usage
@@ -124,6 +125,11 @@ its version and will then offer you to either `build` or `install` it.
 
 You can grab a copy of clue/phar-composer in either of the following ways.
 
+This project aims to run on any platform and thus does not require any PHP
+extensions and supports running on legacy PHP 5.3 through current PHP 7+ and
+HHVM.
+It's *highly recommended to use PHP 7+* for this project.
+
 ### As a phar (recommended)
 
 You can simply download a pre-compiled and ready-to-use version as a Phar
@@ -222,19 +228,34 @@ $ php bin/phar-composer --version
 Optionally, you can now build the above mentioned `phar-composer.phar` yourself by issuing:
 
 ```bash
+$ composer install --no-dev
 $ php bin/phar-composer build
 ```
 
 Optionally, you can now follow the above instructions for a [system-wide installation](#as-a-phar-recommended).
 
-
 #### Updating manually
 
 ```bash
 $ git pull
 $ php composer.phar install
 ```
 
+## Tests
+
+To run the test suite, you first need to clone this repo and then install all
+dependencies [through Composer](http://getcomposer.org):
+
+```bash
+$ composer install
+```
+
+To run the test suite, go to the project root and run:
+
+```bash
+$ php vendor/bin/phpunit
+```
+
 ## License
 
 MIT

composer.json

@@ -17,6 +17,9 @@
         "symfony/process": "~2.1",
         "knplabs/packagist-api": "~1.0"
     },
+    "require-dev": {
+        "phpunit/phpunit": "^4.8"
+    },
     "autoload": {
         "psr-0": {"Clue": "src/"}
     },
@@ -25,5 +28,10 @@
         "phar": {
             "bundler": "composer"
         }
+    },
+    "config": {
+        "platform": {
+            "php": "5.3.6"
+        }
     }
 }