fix: support protocol-relative links

Author: kenjis

system/HTTP/SiteURI.php

@@ -145,7 +145,7 @@ private function determineBaseURL(
         $uri = new URI($baseURL);
 
         // Update scheme
-        if ($scheme !== null) {
+        if ($scheme !== null && $scheme !== '') {
             $uri->setScheme($scheme);
         } elseif ($configApp->forceGlobalSecureRequests) {
             $uri->setScheme('https');
@@ -381,13 +381,12 @@ public function baseUrl($relativePath = '', ?string $scheme = null): string
 
         $uri = new self($config, $relativePath, $host, $scheme);
 
-        return URI::createURIString(
-            $uri->getScheme(),
-            $uri->getAuthority(),
-            $uri->getPath(),
-            $uri->getQuery(),
-            $uri->getFragment()
-        );
+        // Support protocol-relative links
+        if ($scheme === '') {
+            return substr((string) $uri, strlen($uri->getScheme()) + 1);
+        }
+
+        return (string) $uri;
     }
 
     /**
@@ -420,12 +419,11 @@ public function siteUrl($relativePath = '', ?string $scheme = null, ?App $config
 
         $uri = new self($config, $relativePath, $host, $scheme);
 
-        return URI::createURIString(
-            $uri->getScheme(),
-            $uri->getAuthority(),
-            $uri->getPath(),
-            $uri->getQuery(),
-            $uri->getFragment()
-        );
+        // Support protocol-relative links
+        if ($scheme === '') {
+            return substr((string) $uri, strlen($uri->getScheme()) + 1);
+        }
+
+        return (string) $uri;
     }
 }

system/Helpers/url_helper.php

@@ -33,7 +33,6 @@ function site_url($relativePath = '', ?string $scheme = null, ?App $config = nul
 
         assert($currentURI instanceof SiteURI);
 
-        // @TODO supprot protocol-relative links
         return $currentURI->siteUrl($relativePath, $scheme, $config);
     }
 }

tests/system/HTTP/SiteURITest.php

@@ -293,6 +293,17 @@ public function testConstructorScheme()
         $this->assertSame('https://example.com/', $uri->getBaseURL());
     }
 
+    public function testConstructorEmptyScheme()
+    {
+        $config = new App();
+
+        $uri = new SiteURI($config, '', null, '');
+
+        $this->assertInstanceOf(SiteURI::class, $uri);
+        $this->assertSame('http://example.com/index.php', (string) $uri);
+        $this->assertSame('http://example.com/', $uri->getBaseURL());
+    }
+
     public function testConstructorForceGlobalSecureRequests()
     {
         $config                            = new App();