add add_attrs_if_missing callback

src/browser/parser/Parser.zig

@@ -64,6 +64,8 @@ const Error = struct {
         append,
         create_element,
         create_comment,
+        append_doctype_to_document,
+        add_attrs_if_missing,
     };
 };
 
@@ -80,6 +82,7 @@ pub fn parse(self: *Parser, html: []const u8) void {
         popCallback,
         createCommentCallback,
         appendDoctypeToDocument,
+        addAttrsIfMissingCallback,
     );
 }
 
@@ -96,6 +99,7 @@ pub fn parseFragment(self: *Parser, html: []const u8) void {
         popCallback,
         createCommentCallback,
         appendDoctypeToDocument,
+        addAttrsIfMissingCallback,
     );
 }
 
@@ -129,6 +133,7 @@ pub const Streaming = struct {
             popCallback,
             createCommentCallback,
             appendDoctypeToDocument,
+            addAttrsIfMissingCallback,
         ) orelse return error.ParserCreationFailed;
     }
 
@@ -215,6 +220,31 @@ fn _appendDoctypeToDocument(self: *Parser, name: []const u8) !void {
     _ = name;
 }
 
+fn addAttrsIfMissingCallback(ctx: *anyopaque, target_ref: *anyopaque, attributes: h5e.AttributeIterator) callconv(.c) void {
+    const self: *Parser = @ptrCast(@alignCast(ctx));
+    self._addAttrsIfMissingCallback(getNode(target_ref), attributes) catch |err| {
+        self.err = .{ .err = err, .source = .add_attrs_if_missing };
+    };
+}
+fn _addAttrsIfMissingCallback(self: *Parser, node: *Node, attributes: h5e.AttributeIterator) !void {
+    const element = node.as(Element);
+    const page = self.page;
+
+    const attr_list = element._attributes orelse blk: {
+        const a = try page.arena.create(@import("../webapi/element/Attribute.zig").List);
+        a.* = .{};
+        element._attributes = a;
+        break :blk a;
+    };
+
+    while (attributes.next()) |attr| {
+        const name = attr.name.local.slice();
+        const value = attr.value.slice();
+        // putNew only adds if the attribute doesn't already exist
+        try attr_list.putNew(name, value, page);
+    }
+}
+
 fn getDataCallback(ctx: *anyopaque) callconv(.c) *anyopaque {
     const pn: *ParsedNode = @ptrCast(@alignCast(ctx));
     // For non-elements, data is null. But, we expect this to only ever

src/browser/parser/html5ever.zig

@@ -30,6 +30,7 @@ pub extern "c" fn html5ever_parse_document(
     popCallback: *const fn (ctx: *anyopaque, node_ref: *anyopaque) callconv(.c) void,
     createCommentCallback: *const fn (ctx: *anyopaque, StringSlice) callconv(.c) ?*anyopaque,
     appendDoctypeToDocument: *const fn (ctx: *anyopaque, StringSlice, StringSlice, StringSlice) callconv(.c) void,
+    addAttrsIfMissingCallback: *const fn (ctx: *anyopaque, target_ref: *anyopaque, AttributeIterator) callconv(.c) void,
 ) void;
 
 pub extern "c" fn html5ever_parse_fragment(
@@ -44,6 +45,7 @@ pub extern "c" fn html5ever_parse_fragment(
     popCallback: *const fn (ctx: *anyopaque, node_ref: *anyopaque) callconv(.c) void,
     createCommentCallback: *const fn (ctx: *anyopaque, StringSlice) callconv(.c) ?*anyopaque,
     appendDoctypeToDocument: *const fn (ctx: *anyopaque, StringSlice, StringSlice, StringSlice) callconv(.c) void,
+    addAttrsIfMissingCallback: *const fn (ctx: *anyopaque, target_ref: *anyopaque, AttributeIterator) callconv(.c) void,
 ) void;
 
 pub extern "c" fn html5ever_attribute_iterator_next(ctx: *anyopaque) Nullable(Attribute);
@@ -67,6 +69,7 @@ pub extern "c" fn html5ever_streaming_parser_create(
     popCallback: *const fn (ctx: *anyopaque, node_ref: *anyopaque) callconv(.c) void,
     createCommentCallback: *const fn (ctx: *anyopaque, StringSlice) callconv(.c) ?*anyopaque,
     appendDoctypeToDocument: *const fn (ctx: *anyopaque, StringSlice, StringSlice, StringSlice) callconv(.c) void,
+    addAttrsIfMissingCallback: *const fn (ctx: *anyopaque, target_ref: *anyopaque, AttributeIterator) callconv(.c) void,
 ) ?*anyopaque;
 
 pub extern "c" fn html5ever_streaming_parser_feed(

src/html5ever/lib.rs

@@ -44,6 +44,7 @@ pub extern "C" fn html5ever_parse_document(
     pop_callback: PopCallback,
     create_comment_callback: CreateCommentCallback,
     append_doctype_to_document: AppendDoctypeToDocumentCallback,
+    add_attrs_if_missing_callback: AddAttrsIfMissingCallback,
 ) -> () {
     if html.is_null() || len == 0 {
         return ();
@@ -63,6 +64,7 @@ pub extern "C" fn html5ever_parse_document(
         create_element_callback: create_element_callback,
         create_comment_callback: create_comment_callback,
         append_doctype_to_document: append_doctype_to_document,
+        add_attrs_if_missing_callback: add_attrs_if_missing_callback,
     };
 
     let bytes = unsafe { std::slice::from_raw_parts(html, len) };
@@ -84,6 +86,7 @@ pub extern "C" fn html5ever_parse_fragment(
     pop_callback: PopCallback,
     create_comment_callback: CreateCommentCallback,
     append_doctype_to_document: AppendDoctypeToDocumentCallback,
+    add_attrs_if_missing_callback: AddAttrsIfMissingCallback,
 ) -> () {
     if html.is_null() || len == 0 {
         return ();
@@ -103,6 +106,7 @@ pub extern "C" fn html5ever_parse_fragment(
         create_element_callback: create_element_callback,
         create_comment_callback: create_comment_callback,
         append_doctype_to_document: append_doctype_to_document,
+        add_attrs_if_missing_callback: add_attrs_if_missing_callback,
     };
 
     let bytes = unsafe { std::slice::from_raw_parts(html, len) };
@@ -183,6 +187,7 @@ pub extern "C" fn html5ever_streaming_parser_create(
     pop_callback: PopCallback,
     create_comment_callback: CreateCommentCallback,
     append_doctype_to_document: AppendDoctypeToDocumentCallback,
+    add_attrs_if_missing_callback: AddAttrsIfMissingCallback,
 ) -> *mut c_void {
     let arena = Box::new(typed_arena::Arena::new());
 
@@ -205,6 +210,7 @@ pub extern "C" fn html5ever_streaming_parser_create(
         create_element_callback: create_element_callback,
         create_comment_callback: create_comment_callback,
         append_doctype_to_document: append_doctype_to_document,
+        add_attrs_if_missing_callback: add_attrs_if_missing_callback,
     };
 
     // Create a parser which implements TendrilSink for streaming parsing

src/html5ever/sink.rs

@@ -55,6 +55,7 @@ pub struct Sink<'arena> {
     pub create_element_callback: CreateElementCallback,
     pub create_comment_callback: CreateCommentCallback,
     pub append_doctype_to_document: AppendDoctypeToDocumentCallback,
+    pub add_attrs_if_missing_callback: AddAttrsIfMissingCallback,
 }
 
 impl<'arena> TreeSink for Sink<'arena> {
@@ -120,19 +121,6 @@ impl<'arena> TreeSink for Sink<'arena> {
         let data = self.arena.alloc(ElementData::new(name.clone(), flags));
 
         unsafe {
-            let mut c_attrs: Vec<CAttribute> = Vec::with_capacity(attrs.len());
-
-            for attr in attrs.iter() {
-                let v: &str = &attr.value;
-                c_attrs.push(CAttribute {
-                    name: CQualName::create(&attr.name),
-                    value: StringSlice {
-                        ptr: v.as_ptr(),
-                        len: attr.value.len(),
-                    },
-                })
-            }
-
             let mut attribute_iterator = CAttributeIterator { vec: attrs, pos: 0 };
 
             return (self.create_element_callback)(
@@ -226,9 +214,15 @@ impl<'arena> TreeSink for Sink<'arena> {
     }
 
     fn add_attrs_if_missing(&self, target: &Ref, attrs: Vec<Attribute>) {
-        _ = target;
-        _ = attrs;
-        panic!("add_attrs_if_missing");
+        unsafe {
+            let mut attribute_iterator = CAttributeIterator { vec: attrs, pos: 0 };
+
+            (self.add_attrs_if_missing_callback)(
+                self.ctx,
+                *target,
+                &mut attribute_iterator as *mut _ as *mut c_void,
+            );
+        }
     }
 
     fn remove_from_parent(&self, target: &Ref) {

src/html5ever/types.rs

@@ -51,6 +51,12 @@ pub type ParseErrorCallback = unsafe extern "C" fn(ctx: Ref, str: StringSlice) -
 
 pub type PopCallback = unsafe extern "C" fn(ctx: Ref, node: Ref) -> ();
 
+pub type AddAttrsIfMissingCallback = unsafe extern "C" fn(
+    ctx: Ref,
+    target: Ref,
+    attributes: *mut c_void,
+) -> ();
+
 pub type Ref = *const c_void;
 
 #[repr(C)]