From 16e7c0841dc425c2ce51eb07413a6377d4dc99a1 Mon Sep 17 00:00:00 2001
From: Muki Kiboigo <muki@muki.gg>
Date: Mon, 10 Nov 2025 06:52:14 -0800
Subject: [PATCH] handle empty hashes in Location

---
 src/browser/html/location.zig | 19 +++++++++++++------
 src/tests/html/location.html  |  8 ++++++++
 2 files changed, 21 insertions(+), 6 deletions(-)

diff --git a/src/browser/html/location.zig b/src/browser/html/location.zig
index 27dcd335..45817845 100644
--- a/src/browser/html/location.zig
+++ b/src/browser/html/location.zig
@@ -17,8 +17,6 @@
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 const std = @import("std");
-const Uri = std.Uri;
-
 const Page = @import("../page.zig").Page;
 const URL = @import("../url/url.zig").URL;
 
@@ -44,10 +42,19 @@ pub const Location = struct {
     }
 
     pub fn set_hash(_: *const Location, hash: []const u8, page: *Page) !void {
-        const normalized_hash = if (hash[0] == '#')
-            hash
-        else
-            try std.fmt.allocPrint(page.arena, "#{s}", .{hash});
+        const normalized_hash = blk: {
+            if (hash.len == 0) {
+                const old_url = page.url.raw;
+
+                break :blk if (std.mem.indexOfScalar(u8, old_url, '#')) |index|
+                    old_url[0..index]
+                else
+                    old_url;
+            } else if (hash[0] == '#')
+                break :blk hash
+            else
+                break :blk try std.fmt.allocPrint(page.arena, "#{s}", .{hash});
+        };
 
         return page.navigateFromWebAPI(normalized_hash, .{ .reason = .script }, .replace);
     }
diff --git a/src/tests/html/location.html b/src/tests/html/location.html
index 863ae658..a5de3ba8 100644
--- a/src/tests/html/location.html
+++ b/src/tests/html/location.html
@@ -15,6 +15,10 @@
 </script>
 
 <script id=location_hash>
+  location.hash = "";
+  testing.expectEqual("", location.hash);
+  testing.expectEqual('http://localhost:9582/src/tests/html/location.html', location.href);
+
   location.hash = "#abcdef";
   testing.expectEqual("#abcdef", location.hash);
   testing.expectEqual('http://localhost:9582/src/tests/html/location.html#abcdef', location.href);
@@ -22,4 +26,8 @@
   location.hash = "xyzxyz";
   testing.expectEqual("#xyzxyz", location.hash);
   testing.expectEqual('http://localhost:9582/src/tests/html/location.html#xyzxyz', location.href);
+
+  location.hash = "";
+  testing.expectEqual("", location.hash);
+  testing.expectEqual('http://localhost:9582/src/tests/html/location.html', location.href);
 </script>