L01ALG-1072 add AttributesTrait

src/Library/AttributesTrait.php

+<?php
+
+namespace Library;
+
+/**
+ * Trait that adds support for getting/setting attributes/properties.
+ * Useful for settings from a configuration file.
+ * And no need to create getter/setter for each attribute.
+ */
+trait AttributesTrait
+{
+    /**
+     * Attributes of instance
+     *
+     * @var array with key, value pairs
+     */
+    protected $attributes = [];
+
+    /**
+     * Add attributes to existing attributes
+     *
+     * @param array|\ArrayAccess $attributes
+     * @return $this
+     */
+    public function addAttributes($attributes)
+    {
+        // array_merge does not work on \ArrayAccess objects (settings in Slim framework)
+        foreach ($attributes as $key => $value) {
+            $this->attributes[$key] = $value;
+        }
+        return $this;
+    }
+
+    /**
+     * Set attributes, replaces all existing attributes
+     *
+     * @param array|\ArrayAccess $attributes new attributes
+     * @return $this
+     */
+    public function setAttributes($attributes)
+    {
+        $this->attributes = [];
+        return $this->addAttributes($attributes);
+    }
+
+    /**
+     * Return array with all attributes
+     *
+     * @return array key/value array with all attributes
+     */
+    public function getAttributes(): array
+    {
+        return $this->attributes;
+    }
+
+    /**
+     * Set a key/value pair to the attributes
+     *
+     * @param string $key
+     * @param mixed $value
+     * @return $this
+     */
+    public function setAttribute(string $key, $value)
+    {
+        $this->attributes[$key] = $value;
+        return $this;
+    }
+
+    /**
+     * Return the value of the attribute with given key
+     * if the attribute is not set then return the given default value
+     *
+     * @param string $key
+     * @param mixed $default
+     * @return mixed value of attribute with given key of the default value
+     */
+    public function getAttribute(string $key, $default = '')
+    {
+        return key_exists($key, $this->attributes) ? $this->attributes[$key] : $default;
+    }
+}

tests/Library/AttributesTraitTest.php

+<?php
+
+// phpcs:disable Generic.Files.LineLength
+
+namespace Tests\App;
+
+class AttributesTraitTest extends \PHPUnit\Framework\TestCase
+{
+    private $instance;
+
+    protected function setUp(): void
+    {
+        $this->instance = new class {
+            use \Library\AttributesTrait;
+        };
+    }
+
+    public function testDefaultAttributes()
+    {
+        $this->assertEquals([], $this->instance->getAttributes(), 'default attributes');
+    }
+
+    public function testAddAttributes()
+    {
+        $attribs = [
+            "a" => 1,
+        ];
+        $this->instance->addAttributes($attribs);
+        $this->assertEquals($attribs, $this->instance->getAttributes(), 'first set attributes');
+
+        $attribs = [
+            "b" => 2,
+            "c" => 3,
+        ];
+        $this->instance->addAttributes($attribs);
+        $expect = [
+            "a" => 1,
+            "b" => 2,
+            "c" => 3,
+        ];
+        $this->assertEquals($expect, $this->instance->getAttributes(), 'second set attributes');
+    }
+
+    public function testSetAttributes()
+    {
+        $attribs = [
+            "a" => 1,
+        ];
+        $this->instance->setAttributes($attribs);
+        $this->assertEquals($attribs, $this->instance->getAttributes(), 'first set attributes');
+
+        $attribs = [
+            "b" => 2,
+            "c" => 3,
+        ];
+        $this->instance->setAttributes($attribs);
+        $this->assertEquals($attribs, $this->instance->getAttributes(), 'second set attributes');
+    }
+
+    public function testSetAttribute()
+    {
+        $this->instance->setAttribute("a", 1);
+        $expect = [
+            "a" => 1,
+        ];
+        $this->assertEquals($expect, $this->instance->getAttributes(), 'attribute "a" set');
+
+        $this->instance->setAttribute("b", 2);
+        $expect = [
+            "a" => 1,
+            "b" => 2,
+        ];
+        $this->assertEquals($expect, $this->instance->getAttributes(), 'attribute "b" set');
+
+        $this->instance->setAttribute("a", 3);
+        $expect = [
+            "a" => 3,
+            "b" => 2,
+        ];
+        $this->assertEquals($expect, $this->instance->getAttributes(), 'attribute "a" changed');
+    }
+
+    public function testGetAttribute()
+    {
+        $attribs = [
+            "a" => 1,
+            "b" => 2,
+            "c" => 3,
+        ];
+        $this->instance->addAttributes($attribs);
+
+        $this->assertEquals(1, $this->instance->getAttribute("a"), 'get attribute "a" without default');
+        $this->assertEquals(1, $this->instance->getAttribute("a", "x"), 'get attribute "a" with default');
+        $this->assertEquals(2, $this->instance->getAttribute("b"), 'get attribute "b" without default');
+        $this->assertEquals(3, $this->instance->getAttribute("c"), 'get attribute "c" without default');
+        $this->assertEquals(null, $this->instance->getAttribute("d"), 'get unknown attribute "d" without default');
+        $this->assertEquals("x", $this->instance->getAttribute("d", "x"), 'get unknown attribute "d" with default');
+    }
+}