Add addLast() function

.gitignore

@@ -1,3 +1,4 @@
+.idea
 composer.phar
 /vendor/
 .phpunit.result.cache

docs/04-functions.md

@@ -17,6 +17,7 @@ or [fromBucket()](functions/fromBucket.md)
 or [addRangeInBetween()](functions/addRangeInBetween.md)
 * [addReduce()](functions/addReduce.md)
 * [addSum()](functions/addSum.md)
+* [addLast()](functions/addLast.md)
 
 Anything missing here? You can use this method to add anything to the query:
 * [addRawFunction()](functions/addRawFunction.md)

docs/functions/addLast.md

@@ -0,0 +1,39 @@
+# Flux Query Builder Docs
+
+## Functions » addLast()
+
+### Parameters:
+
+<table>
+  <tbody>
+    <tr>
+      <th>Name</th>
+      <th>Required</th>
+      <th>Data type</th>
+      <th>Description</th>
+    </tr>
+    <tr>
+      <td>column</td>
+      <td>No</td>
+      <td>string</td>
+      <td>Column to use to verify the existence of a value. Default is "_value".</td>
+    </tr>
+  </tbody>
+</table>
+
+
+### Example
+
+```php
+->addLast('something')
+```
+
+This will result in the following Flux function part:
+
+```
+|> last(column: "something")
+```
+
+### Extra resources
+
+* [Flux documentation](https://docs.influxdata.com/flux/v0.x/stdlib/universe/last/)

src/Builder/Universe.php

@@ -5,6 +5,7 @@ namespace Arendsen\FluxQueryBuilder\Builder;
 use Arendsen\FluxQueryBuilder\Builder\QueryBuilderInterface;
 use Arendsen\FluxQueryBuilder\Functions\AggregateWindow;
 use Arendsen\FluxQueryBuilder\Functions\Duplicate;
+use Arendsen\FluxQueryBuilder\Functions\Last;
 use Arendsen\FluxQueryBuilder\Functions\Reduce;
 use Arendsen\FluxQueryBuilder\Functions\Sort;
 use Arendsen\FluxQueryBuilder\Functions\Map;
@@ -103,4 +104,12 @@ trait Universe
         );
         return $this;
     }
+
+	public function addLast(string $column = '_value'): QueryBuilderInterface
+	{
+		$this->addToQuery(
+			new Last($column)
+		);
+		return $this;
+	}
 }

src/Functions/Last.php

@@ -0,0 +1,21 @@
+<?php
+
+namespace Arendsen\FluxQueryBuilder\Functions;
+
+class Last extends Base
+{
+	/**
+	 * @var int $column
+	 */
+	private $column;
+
+	public function __construct(string $column = '_value')
+	{
+		$this->column = $column;
+	}
+
+	public function __toString()
+	{
+		return '|> last(column: ' . (string)$this->column . ') ';
+	}
+}

tests/Functions/LastFunctionTest.php

@@ -0,0 +1,29 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Tests\Functions;
+
+use Arendsen\FluxQueryBuilder\Functions\Last;
+use PHPUnit\Framework\TestCase;
+
+final class LastFunctionTest extends TestCase
+{
+	public function testSimpleLast()
+	{
+		$expression = new Last();
+
+		$query = '|> last(column: "_value") ';
+
+		$this->assertEquals($query, $expression->__toString());
+	}
+
+	public function testLastWithValue()
+	{
+		$expression = new Last('something');
+
+		$query = '|> last(column: "something") ';
+
+		$this->assertEquals($query, $expression->__toString());
+	}
+}