Arrays::insertBefore and Arrays::insertAfter added

Author: Pechynho

src/Arrays.php

@@ -777,6 +777,64 @@ public static function mapByProperty($subject, $keyPropertyPath)
 		return $output;
 	}
 
+	/**
+	 * @param array      $subject
+	 * @param string|int $key
+	 * @param mixed      $value
+	 * @param string|int $insertAfterKey
+	 * @return array
+	 */
+	public static function insertAfter(array $subject, $key, $value, $insertAfterKey)
+	{
+		ParamsChecker::isIntOrString('$key', $key, __METHOD__);
+		ParamsChecker::isIntOrString('$insertAfterKey', $insertAfterKey, __METHOD__);
+		$output = [];
+		$inserted = false;
+		foreach ($subject as $i => $item)
+		{
+			$output[$i] = $item;
+			if (!$inserted && $i == $insertAfterKey)
+			{
+				$output[$key] = $value;
+				$inserted = true;
+			}
+		}
+		if (!$inserted)
+		{
+			$output[$key] = $value;
+		}
+		return $output;
+	}
+
+	/**
+	 * @param array      $subject
+	 * @param string|int $key
+	 * @param mixed      $value
+	 * @param string|int $insertBeforeKey
+	 * @return array
+	 */
+	public static function insertBefore(array $subject, $key, $value, $insertBeforeKey)
+	{
+		ParamsChecker::isIntOrString('$key', $key, __METHOD__);
+		ParamsChecker::isIntOrString('$insertBeforeKey', $insertBeforeKey, __METHOD__);
+		$output = [];
+		$inserted = false;
+		foreach ($subject as $i => $item)
+		{
+			if (!$inserted && $i == $insertBeforeKey)
+			{
+				$output[$key] = $value;
+				$inserted = true;
+			}
+			$output[$i] = $item;
+		}
+		if (!$inserted)
+		{
+			$output[$key] = $value;
+		}
+		return $output;
+	}
+
 	/**
 	 * @param array  $subject
 	 * @param string $keyPath

tests/ArraysTest.php

@@ -302,4 +302,27 @@ public function testMergeArrayConfig()
 		self::assertException(function () use ($config, $defaultConfig) { Arrays::mergeArrayConfig($config, $defaultConfig, "blue"); }, InvalidArgumentException::class);
 	}
 
+	public static function testInsertAfter()
+	{
+		$target = ["one" => 1, "three" => 3];
+		self::assertEquals(["one" => 1, "two" => 2, "three" => 3], Arrays::insertAfter($target, "two", 2, "one"));
+		self::assertEquals(["one" => 1, "three" => 3, "key" => "key"], Arrays::insertAfter($target, "key", "key", "two"));
+		$target = [1 => 1, 3 => 3];
+		self::assertEquals([1 => 1, 2 => 2, 3 => 3], Arrays::insertAfter($target, 2, 2, 1));
+		self::assertEquals([1 => 1], Arrays::insertAfter([], 1, 1, "one"));
+		self::assertException(function () use ($target) { Arrays::insertAfter($target, null, 2, "one"); }, InvalidArgumentException::class);
+		self::assertException(function () use ($target) { Arrays::insertAfter($target, 2, 2, null); }, InvalidArgumentException::class);
+	}
+
+	public static function testInsertBefore()
+	{
+		$target = ["one" => 1, "three" => 3];
+		self::assertEquals(["one" => 1, "two" => 2, "three" => 3], Arrays::insertBefore($target, "two", 2, "three"));
+		self::assertEquals(["one" => 1, "three" => 3, "key" => "key"], Arrays::insertBefore($target, "key", "key", "two"));
+		$target = [1 => 1, 3 => 3];
+		self::assertEquals([1 => 1, 2 => 2, 3 => 3], Arrays::insertBefore($target, 2, 2, 3));
+		self::assertEquals([1 => 1], Arrays::insertBefore([], 1, 1, "one"));
+		self::assertException(function () use ($target) { Arrays::insertBefore($target, null, 2, "one"); }, InvalidArgumentException::class);
+		self::assertException(function () use ($target) { Arrays::insertBefore($target, 2, 2, null); }, InvalidArgumentException::class);
+	}
 }