From abc9e06ed10fc0f73ae2f6b7876c16204be03d09 Mon Sep 17 00:00:00 2001
From: shove <shove@163.com>
Date: Sat, 13 Jan 2024 04:51:48 +0800
Subject: [PATCH] net.urllib: fix parsing url error, when querypath is '//'
 (fix #20476) (#20504)

---
 vlib/net/urllib/urllib.v      |  3 ++-
 vlib/net/urllib/urllib_test.v |  6 ++++++
 vlib/vweb/tests/vweb_test.v   | 13 +++++++++++++
 3 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/vlib/net/urllib/urllib.v b/vlib/net/urllib/urllib.v
index 90b27fec37cb0d..11aa93680a1fe6 100644
--- a/vlib/net/urllib/urllib.v
+++ b/vlib/net/urllib/urllib.v
@@ -512,7 +512,8 @@ fn parse_url(rawurl string, via_request bool) !URL {
 				''))
 		}
 	}
-	if ((url.scheme != '' || !via_request) && !rest.starts_with('///')) && rest.starts_with('//') {
+	if ((url.scheme != '' || !via_request) && !rest.starts_with('///')) && rest.starts_with('//')
+		&& rest.len > 2 {
 		authority, r := split(rest[2..], `/`, false)
 		rest = r
 		a := parse_authority(authority)!
diff --git a/vlib/net/urllib/urllib_test.v b/vlib/net/urllib/urllib_test.v
index 679169a0585363..939839df5e912b 100644
--- a/vlib/net/urllib/urllib_test.v
+++ b/vlib/net/urllib/urllib_test.v
@@ -122,3 +122,9 @@ fn test_parse() {
 		}
 	}
 }
+
+fn test_parse_slashes() {
+	assert urllib.parse('/')!.str() == '/'
+	assert urllib.parse('//')!.str() == '//'
+	assert urllib.parse('///')!.str() == '///'
+}
diff --git a/vlib/vweb/tests/vweb_test.v b/vlib/vweb/tests/vweb_test.v
index 4d82c7fb1262ce..e222cc2e299f62 100644
--- a/vlib/vweb/tests/vweb_test.v
+++ b/vlib/vweb/tests/vweb_test.v
@@ -339,3 +339,16 @@ ${config.content}'
 	}
 	return read.bytestr()
 }
+
+// for issue 20476
+// phenomenon: parsing url error when querypath is `//`
+fn test_empty_querypath() {
+	mut x := http.get('http://${localserver}') or { panic(err) }
+	assert x.body == 'Welcome to VWeb'
+	x = http.get('http://${localserver}/') or { panic(err) }
+	assert x.body == 'Welcome to VWeb'
+	x = http.get('http://${localserver}//') or { panic(err) }
+	assert x.body == 'Welcome to VWeb'
+	x = http.get('http://${localserver}///') or { panic(err) }
+	assert x.body == 'Welcome to VWeb'
+}