Url: added isAbsolute() & removeDotSegments()

Author: dg

src/Http/Url.php

@@ -409,4 +409,40 @@ public static function parseQuery(string $s): array
 		parse_str($s, $res);
 		return $res[0] ?? [];
 	}
+
+
+	/**
+	 * Determines if URL is absolute, ie if it starts with a scheme followed by colon.
+	 */
+	public static function isAbsolute(string $url): bool
+	{
+		return (bool) preg_match('#^[a-z][a-z0-9+.-]*:#i', $url);
+	}
+
+
+	/**
+	 * Normalizes a path by handling and removing relative path references like '.', '..' and directory traversal.
+	 */
+	public static function removeDotSegments(string $path): string
+	{
+		$prefix = $segment = '';
+		if (str_starts_with($path, '/')) {
+			$prefix = '/';
+			$path = substr($path, 1);
+		}
+		$segments = explode('/', $path);
+		$res = [];
+		foreach ($segments as $segment) {
+			if ($segment === '..') {
+				array_pop($res);
+			} elseif ($segment !== '.') {
+				$res[] = $segment;
+			}
+		}
+
+		if ($segment === '.' || $segment === '..') {
+			$res[] = '';
+		}
+		return $prefix . implode('/', $res);
+	}
 }

tests/Http/Url.isAbsolute.phpt

@@ -0,0 +1,15 @@
+<?php
+
+declare(strict_types=1);
+
+use Nette\Http\Url;
+use Tester\Assert;
+
+require __DIR__ . '/../bootstrap.php';
+
+
+Assert::false(Url::isAbsolute('/'));
+Assert::false(Url::isAbsolute('//'));
+Assert::false(Url::isAbsolute(''));
+Assert::false(Url::isAbsolute('https'));
+Assert::true(Url::isAbsolute('https:'));

tests/Http/Url.removeDotSegments.phpt

@@ -0,0 +1,55 @@
+<?php
+
+declare(strict_types=1);
+
+use Nette\Http\Url;
+use Tester\Assert;
+
+require __DIR__ . '/../bootstrap.php';
+
+
+test('begins with /', function () {
+	Assert::same('/', Url::removeDotSegments('/'));
+	Assert::same('/file', Url::removeDotSegments('/file'));
+	Assert::same('/file/', Url::removeDotSegments('/file/'));
+
+	Assert::same('/', Url::removeDotSegments('/.'));
+	Assert::same('/', Url::removeDotSegments('/./'));
+
+	Assert::same('/file/', Url::removeDotSegments('/file/.'));
+	Assert::same('/', Url::removeDotSegments('/file/..'));
+	Assert::same('/', Url::removeDotSegments('/file/../'));
+	Assert::same('/file', Url::removeDotSegments('/./file'));
+});
+
+
+test('not begins with /', function () {
+	Assert::same('', Url::removeDotSegments(''));
+	Assert::same('file', Url::removeDotSegments('file'));
+	Assert::same('file/', Url::removeDotSegments('file/'));
+
+	Assert::same('', Url::removeDotSegments('.'));
+	Assert::same('', Url::removeDotSegments('./'));
+
+	Assert::same('file/', Url::removeDotSegments('file/.'));
+	Assert::same('', Url::removeDotSegments('file/..'));
+	Assert::same('', Url::removeDotSegments('file/../'));
+	Assert::same('file', Url::removeDotSegments('./file'));
+});
+
+
+test('incorrect ..', function () {
+	Assert::same('/', Url::removeDotSegments('/file/../..'));
+	Assert::same('/', Url::removeDotSegments('/file/../../'));
+	Assert::same('/bar', Url::removeDotSegments('/file/../../bar'));
+	Assert::same('/file', Url::removeDotSegments('/../file'));
+	Assert::same('/bar', Url::removeDotSegments('/file/./.././.././bar'));
+	Assert::same('/bar/', Url::removeDotSegments('/file/./.././.././bar/'));
+});
+
+
+test('double slash', function () {
+	Assert::same('//', Url::removeDotSegments('//'));
+	Assert::same('//foo//', Url::removeDotSegments('//foo//'));
+	Assert::same('//foo//', Url::removeDotSegments('//foo//..//'));
+});