From f82eb268379979e19f1af3d44f849d22062a31ab Mon Sep 17 00:00:00 2001
From: Corey Farwell <coreyf@rwell.org>
Date: Fri, 2 Dec 2016 10:16:17 -0500
Subject: [PATCH] Prevent panic when calling `url::Url::set_host` with `None`.

Fixes https://github.com/servo/rust-url/issues/243.
---
 src/lib.rs    | 2 +-
 tests/unit.rs | 9 +++++++++
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/src/lib.rs b/src/lib.rs
index 89e08c3c2..2fca96310 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1003,7 +1003,7 @@ impl Url {
             debug_assert!(self.byte_at(self.scheme_end) == b':');
             debug_assert!(self.byte_at(self.path_start) == b'/');
             let new_path_start = self.scheme_end + 1;
-            self.serialization.drain(self.path_start as usize..new_path_start as usize);
+            self.serialization.drain(new_path_start as usize..self.path_start as usize);
             let offset = self.path_start - new_path_start;
             self.path_start = new_path_start;
             self.username_end = new_path_start;
diff --git a/tests/unit.rs b/tests/unit.rs
index eb460015d..93ad1440c 100644
--- a/tests/unit.rs
+++ b/tests/unit.rs
@@ -317,3 +317,12 @@ fn append_empty_segment_then_mutate() {
     url.assert_invariants();
     assert_eq!(url.to_string(), "http://localhost:6767/foo/bar?a=b");
 }
+
+#[test]
+fn test_set_host() {
+    let mut url = Url::parse("https://example.net/hello").unwrap();
+    url.set_host(Some("foo.com")).unwrap();
+    assert_eq!(url.as_str(), "https://foo.com/hello");
+    url.set_host(None).unwrap();
+    assert_eq!(url.as_str(), "https:/hello");
+}