load aboutblank doc to set window

sjorsdonkers · sjorsdonkers · commit 01ce0862404b · 2025-05-12T13:12:06.000+02:00
diff --git a/src/browser/browser.zig b/src/browser/browser.zig
@@ -335,6 +335,8 @@ pub const Page = struct {
 
         // if the url is about:blank, nothing to do.
         if (std.mem.eql(u8, "about:blank", request_url.raw)) {
+            var about_blank = AboutBlank{};
+            try self.loadHTMLDoc(&about_blank, "utf-8");
             return;
         }
 
@@ -393,6 +395,26 @@ pub const Page = struct {
         });
     }
 
+    // A minimal reader for about:blank such that it can be parsed by loadHTMLDoc.
+    pub const AboutBlank = struct {
+        const content =
+            \\ <!DOCTYPE html>
+            \\ <html>
+            \\ <head>
+            \\     <title></title>
+            \\ </head>
+            \\ <body>
+            \\ </body>
+            \\ </html>
+        ;
+        done: bool = false,
+        pub fn next(self: *AboutBlank) !?[]const u8 {
+            if (self.done) return null;
+            self.done = true;
+            return AboutBlank.content;
+        }
+    };
+
     // https://html.spec.whatwg.org/#read-html
     fn loadHTMLDoc(self: *Page, reader: anytype, charset: []const u8) !void {
         const arena = self.arena;
diff --git a/src/cdp/domains/target.zig b/src/cdp/domains/target.zig
@@ -125,6 +125,10 @@ fn createTarget(cmd: anytype) !void {
     bc.target_id = target_id;
 
     var page = try bc.session.createPage();
+    // Navigate to about:blank such that the window / state.document are created and set
+    // Playwright uses these before navigating to a real URL to detect when they are removed.
+    const url = try @import("../../url.zig").URL.parse("about:blank", "");
+    try page.navigate(url, .{});
     {
         const aux_data = try std.fmt.allocPrint(cmd.arena, "{{\"isDefault\":true,\"type\":\"default\",\"frameId\":\"{s}\"}}", .{target_id});
         bc.inspector.contextCreated(
@@ -501,6 +505,11 @@ test "cdp.target: createTarget" {
         // should create a browser context
         const bc = ctx.cdp().browser_context.?;
         try ctx.expectSentEvent("Target.targetCreated", .{ .targetInfo = .{ .url = "about:blank", .title = "about:blank", .attached = false, .type = "page", .canAccessOpener = false, .browserContextId = bc.id, .targetId = bc.target_id.? } }, .{});
+
+        // Even about:blank should set the window and document
+        const page = ctx.cdp().browser_context.?.session.page.?;
+        try testing.expect(page.state.document != null);
+        try testing.expect(page.window.document != null);
     }
 
     {
