feat: add unit test action (#2)

_test/demo-package/composer.json

@@ -9,6 +9,9 @@
             "email": "damienwebdev@gmail.com"
         }
     ],
+    "scripts": {
+        "test": "./vendor/bin/phpunit Test/Unit"
+    },
     "archive": {
         "exclude": [
             "/docs",
@@ -37,5 +40,8 @@
     "config": {
         "preferred-install": "dist",
         "sort-packages": true
+    },
+    "require-dev": {
+        "phpunit/phpunit": "^9.5"
     }
 }

_test/demo-package/phpunit.xml

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:noNamespaceSchemaLocation="https://schema.phpunit.de/9.3/phpunit.xsd"
+         colors="true"
+         columns="max"
+         beStrictAboutTestsThatDoNotTestAnything="false">
+    <php>
+        <ini name="memory_limit" value="-1"/>
+        <ini name="date.timezone" value="America/Los_Angeles"/>
+        <ini name="xdebug.max_nesting_level" value="200"/>
+    </php>
+</phpunit>