add CustomElementRegistry

src/browser/css/parser.zig

@@ -605,6 +605,7 @@ pub const Parser = struct {
             .after, .backdrop, .before, .cue, .first_letter => return .{ .pseudo_element = pseudo_class },
             .first_line, .grammar_error, .marker, .placeholder => return .{ .pseudo_element = pseudo_class },
             .selection, .spelling_error => return .{ .pseudo_element = pseudo_class },
+            .modal => return .{ .pseudo_element = pseudo_class },
         }
     }
 

src/browser/css/selector.zig

@@ -98,6 +98,7 @@ pub const PseudoClass = enum {
     placeholder,
     selection,
     spelling_error,
+    modal,
 
     pub const Error = error{
         InvalidPseudoClass,
@@ -154,6 +155,7 @@ pub const PseudoClass = enum {
         if (std.ascii.eqlIgnoreCase(s, "placeholder")) return .placeholder;
         if (std.ascii.eqlIgnoreCase(s, "selection")) return .selection;
         if (std.ascii.eqlIgnoreCase(s, "spelling-error")) return .spelling_error;
+        if (std.ascii.eqlIgnoreCase(s, "modal")) return .modal;
         return Error.InvalidPseudoClass;
     }
 };

src/browser/cssom/css_style_declaration.zig

@@ -85,7 +85,7 @@ pub const CSSStyleDeclaration = struct {
         return self.order.items.len;
     }
 
-    pub fn get_parentRule() ?CSSRule {
+    pub fn get_parentRule(_: *const CSSStyleDeclaration) ?CSSRule {
         return null;
     }
 

src/browser/dom/document.zig

@@ -18,6 +18,7 @@
 
 const std = @import("std");
 
+const log = @import("../../log.zig");
 const parser = @import("../netsurf.zig");
 const Page = @import("../page.zig").Page;
 
@@ -120,9 +121,28 @@ pub const Document = struct {
         return try Element.toInterface(e);
     }
 
-    pub fn _createElement(self: *parser.Document, tag_name: []const u8) !ElementUnion {
-        const e = try parser.documentCreateElement(self, tag_name);
-        return try Element.toInterface(e);
+    const CreateElementResult = union(enum) {
+        element: ElementUnion,
+        custom: Env.JsObject,
+    };
+
+    pub fn _createElement(self: *parser.Document, tag_name: []const u8, page: *Page) !CreateElementResult {
+        const custom_element = page.window.custom_elements._get(tag_name) orelse {
+            const e = try parser.documentCreateElement(self, tag_name);
+            return .{ .element = try Element.toInterface(e) };
+        };
+
+        var result: Env.Function.Result = undefined;
+        const js_obj = custom_element.newInstance(&result) catch |err| {
+            log.fatal(.user_script, "newInstance error", .{
+                .err = result.exception,
+                .stack = result.stack,
+                .tag_name = tag_name,
+                .source = "createElement",
+            });
+            return err;
+        };
+        return .{ .custom = js_obj };
     }
 
     pub fn _createElementNS(self: *parser.Document, ns: []const u8, tag_name: []const u8) !ElementUnion {

src/browser/env.zig

@@ -33,6 +33,7 @@ const WebApis = struct {
         @import("xhr/xhr.zig").Interfaces,
         @import("xhr/form_data.zig").Interfaces,
         @import("xmlserializer/xmlserializer.zig").Interfaces,
+        @import("webcomponents/webcomponents.zig").Interfaces,
     });
 };