Panic when using HTMLLinkElement.relList after setting HTMLLinkElement.rel

[jdm]

<script>
var l = document.createElement('link');
l.rel = "noreferrer";
l.relList.add("stylesheet");
</script>

yields

ERROR:servo: Tokens not found
Process 72828 stopped
* thread #21: tid = 0x34c99d, 0x0000000104b7c930 servo`rust_panic, stop reason = breakpoint 1.1
    frame #0: 0x0000000104b7c930 servo`rust_panic
servo`rust_panic:
-> 0x104b7c930:  pushq  %rbp
   0x104b7c931:  movq   %rsp, %rbp
   0x104b7c934:  subq   $0x90, %rsp
   0x104b7c93b:  callq  0x104b7d770               ; __rust_start_panic
(lldb) bt
error: need to add support for DW_TAG_base_type '()' encoded with DW_ATE = 0x7, bit_size = 0
* thread #21: tid = 0x34c99d, 0x0000000104b7c930 servo`rust_panic, stop reason = breakpoint 1.1
  * frame #0: 0x0000000104b7c930 servo`rust_panic
    frame #1: 0x0000000104b7c89d servo`std::panicking::rust_panic_with_hook::h105c3d42fcd2fb5e + 413
    frame #2: 0x0000000103bbcd48 servo`{{inlined-root}}::begin_panic<&str>(msg=&str at 0x000000011d5ead70, file_line=0x0000000105fe4b40) + 120 at panicking.rs:328
    frame #3: 0x0000000103d0d4e7 servo`style::attr::{{impl}}::as_tokens(self=0x000000011e63b118) + 119 at <std macros>:3
    frame #4: 0x00000001024b4484 servo`script::dom::element::{{impl}}::get_tokenlist_attribute::{{closure}}(attr=Root<script::dom::attr::Attr> at 0x000000011d5eae98) + 180 at element.rs:1214
    frame #5: 0x000000010149f818 servo`{{inlined-root}}::map<script::dom::bindings::js::Root<script::dom::attr::Attr>,collections::vec::Vec<string_cache::atom::Atom>,closure>(self=Option<script::dom::bindings::js::Root<script::dom::attr::Attr>> at 0x000000011d5eaf38, f=closure at 0x000000011d5eaf30) + 136 at option.rs:386
    frame #6: 0x00000001022e178e servo`script::dom::element::{{impl}}::get_tokenlist_attribute(self=0x000000011e664300, local_name=0x000000011e61f270) + 110 at element.rs:1213
    frame #7: 0x00000001022d6f1e servo`script::dom::domtokenlist::{{impl}}::Add(self=0x000000011e61f260, tokens=Vec<script::dom::bindings::str::DOMString> at 0x000000011d5eb208) + 158 at domtokenlist.rs:86
    frame #8: 0x00000001027889e3 servo`script::dom::bindings::codegen::Bindings::DOMTokenListBinding::add::{{closure}} + 1139 at DOMTokenListBinding.rs:275
    frame #9: 0x0000000102788c29 servo`extern$u20$$u22$rust.call$u22$$u20$fn$LP$$u5b$closure$SP$$u2f$Users$u2f$jdm$u2f$src$u2f$servo$u2f$target$u2f$debug$u2f$build$u2f$script.b33cff3c53b753bb$u2f$out$u2f$Bindings$u2f$DOMTokenListBinding.rs.260.55.$u20$286.22$u20$this.$RF$$BP$const$u20$dom..domtokenlist..DOMTokenList$C$$u20$args.$RF$$BP$const$u20$js..jsapi..JSJitMethodCallArgs$C$$u20$cx.$RF$$BP$mut$u20$js..jsapi..JSContext$u5d$$C$$u20$$LP$$RP$$RP$$u20$.$GT$$u20$bool::once_shim.78536::h7335bb579241bd83 + 9
    frame #10: 0x0000000101e14983 servo`{{inlined-root}}::call_once<bool,closure>(self=AssertUnwindSafe<closure> at 0x000000011d5eb528, _args=<unavailable>) + 67 at panic.rs:256
    frame #11: 0x000000010252d264 servo`std::panicking::try::_$u7b$$u7b$closure$u7d$$u7d$::_$u7b$$u7b$closure$u7d$$u7d$::h9feb3384412ce64d + 68
    frame #12: 0x0000000101716d25 servo`{{inlined-root}}::call<closure>(f=0x000000011d5eb668) + 21 at panicking.rs:272
    frame #13: 0x0000000104b7d71b servo`__rust_maybe_catch_panic + 27
    frame #14: 0x000000010252d1ce servo`std::panicking::try::_$u7b$$u7b$closure$u7d$$u7d$::h3c9306b1b63cc624 + 158
    frame #15: 0x00000001017ddca0 servo`{{inlined-root}}::with<core::cell::Cell<usize>,closure,core::result::Result<(self=0x00000001060b9760, f=closure at 0x000000011d5eb708), Box<Any>>> + 208 at local.rs:245
    frame #16: 0x0000000101670444 servo`{{inlined-root}}::try<bool,std::panic::AssertUnwindSafe<closure>>(f=AssertUnwindSafe<closure> at 0x000000011d5eb7c8) + 132 at panicking.rs:235
    frame #17: 0x000000010160486a servo`{{inlined-root}}::catch_unwind<std::panic::AssertUnwindSafe<closure>,bool>(f=AssertUnwindSafe<closure> at 0x000000011d5eb818) + 74 at panic.rs:312
    frame #18: 0x0000000102001208 servo`script::dom::bindings::codegen::Bindings::DOMTokenListBinding::add(cx=0x000000011113cc00, _obj=Handle<*mut js::jsapi::JSObject> at 0x000000011d5eb8f0, this=0x000000011e61f260, args=0x000000011d5eb940) + 72 at DOMTokenListBinding.rs:260
    frame #19: 0x0000000102ba9e3c servo`CallJitMethodOp(info=0x0000000105e84ea8, cx=0x000000011113cc00, thisObj=JS::HandleObject at 0x000000011d5eb998, specializedThis=0x000000011e61f260, argc=1, vp=0x000000011414c690) + 124 at jsglue.cpp:472
    frame #20: 0x0000000101f592fd servo`script::dom::bindings::utils::generic_call(cx=0x000000011113cc00, argc=1, vp=0x000000011414c690, is_lenient=false, call=0x0000000102ba9dc0) + 3325 at utils.rs:484
    frame #21: 0x0000000101f5937c servo`script::dom::bindings::utils::generic_method(cx=0x000000011113cc00, argc=1, vp=0x000000011414c690) + 44 at utils.rs:492
    frame #22: 0x00000001035a355b servo`js::CallJSNative(cx=0x000000011113cc00, native=0x0000000101f59350, args=0x000000011d5ee1a8)(JSContext*, unsigned int, JS::Value*), JS::CallArgs const&) + 187 at jscntxtinlines.h:232
    frame #23: 0x000000010357daf3 servo`js::InternalCallOrConstruct(cx=0x000000011113cc00, args=0x000000011d5ee1a8, construct=NO_CONSTRUCT) + 1091 at Interpreter.cpp:453
    frame #24: 0x000000010357dee8 servo`InternalCall(cx=0x000000011113cc00, args=0x000000011d5ee1a8) + 504 at Interpreter.cpp:498
    frame #25: 0x000000010357dcdd servo`js::CallFromStack(cx=0x000000011113cc00, args=0x000000011d5ee1a8) + 29 at Interpreter.cpp:504
    frame #26: 0x000000010357284f servo`Interpret(cx=0x000000011113cc00, state=0x000000011d5ef2b0) + 44687 at Interpreter.cpp:2873
    frame #27: 0x00000001035678bf servo`js::RunScript(cx=0x000000011113cc00, state=0x000000011d5ef2b0) + 799 at Interpreter.cpp:399
    frame #28: 0x000000010357ef08 servo`js::ExecuteKernel(cx=0x000000011113cc00, script=JS::HandleScript at 0x000000011d5ef370, scopeChainArg=0x000000011d104070, newTargetValue=0x000000011d5ef3c0, evalInFrame=AbstractFramePtr at 0x000000011d5ef368, result=0x000000011d5f00b0) + 776 at Interpreter.cpp:679
    frame #29: 0x000000010357f29d servo`js::Execute(cx=0x000000011113cc00, script=JS::HandleScript at 0x000000011d5ef418, scopeChainArg=0x000000011d104070, rval=0x000000011d5f00b0) + 813 at Interpreter.cpp:711
    frame #30: 0x000000010326ed1e servo`Evaluate(cx=0x000000011113cc00, scope=JS::HandleObject at 0x000000011d5ef550, staticScope=Handle<js::StaticScope *> at 0x000000011d5ef548, optionsArg=0x000000010fc79460, srcBuf=0x000000011d5ef6e0, rval=JS::MutableHandleValue at 0x000000011d5ef540) + 1182 at jsapi.cpp:4406
    frame #31: 0x000000010326efa7 servo`Evaluate(cx=0x000000011113cc00, optionsArg=0x000000010fc79460, chars=0x000000011e6670c0, length=92, rval=JS::MutableHandleValue at 0x000000011d5ef718) + 263 at jsapi.cpp:4443
    frame #32: 0x000000010326ee8d servo`JS::Evaluate(cx=0x000000011113cc00, optionsArg=0x000000010fc79460, chars=0x000000011e6670c0, length=92, rval=JS::MutableHandleValue at 0x000000011d5ef758) + 61 at jsapi.cpp:4501
    frame #33: 0x00000001024a71ce servo`script::dom::window::{{impl}}::evaluate_script_on_global_with_result::{{closure}}<script::dom::window::Window> + 878 at window.rs:951
    frame #34: 0x000000010135d24f servo`{{inlined-root}}::profile<(category=ScriptEvaluate, meta=Option<profile_traits::time::TimerMetadata> at 0x000000011d5efbc8, profiler_chan=ProfilerChan at 0x000000011d5efbc0, callback=closure at 0x000000011d5efb98),closure> + 239 at time.rs:108
    frame #35: 0x00000001024195a0 servo`script::dom::window::{{impl}}::evaluate_script_on_global_with_result<script::dom::window::Window>(self=0x000000011e638800, code=&str at 0x000000011d5efd90, filename=&str at 0x000000011d5efd80, rval=MutableHandle<js::jsapi::Value> at 0x000000011d5efd78) + 720 at window.rs:938
    frame #36: 0x000000010236996b servo`script::dom::htmlscriptelement::{{impl}}::execute(self=0x000000011e636400) + 3515 at htmlscriptelement.rs:467
    frame #37: 0x00000001023689d9 servo`script::dom::htmlscriptelement::{{impl}}::prepare(self=0x000000011e636400) + 7785 at htmlscriptelement.rs:403
    frame #38: 0x0000000102446948 servo`script::parse::html::{{impl}}::complete_script(self=0x000000011e642338, node=JS<script::dom::node::Node> at 0x000000011d5f1258) + 72 at html.rs:159
    frame #39: 0x0000000101330325 servo`{{inlined-root}}::step<script::dom::bindings::js::JS<script::dom::node::Node>,script::dom::servohtmlparser::Sink>(self=0x000000011e642330, mode=Text, token=Token at 0x000000011d5f7d78) + 55525 at rules.expanded.rs:1461
    frame #40: 0x0000000101cf9ea5 servo`{{inlined-root}}::process_to_completion<script::dom::bindings::js::JS<script::dom::node::Node>,script::dom::servohtmlparser::Sink>(self=0x000000011e642330, token=Token at 0x000000011d5f8580) + 613 at mod.rs:320
    frame #41: 0x000000010131c5ad servo`{{inlined-root}}::process_token<script::dom::bindings::js::JS<script::dom::node::Node>,script::dom::servohtmlparser::Sink>(self=0x000000011e642330, token=Token at 0x000000011d5f8a30) + 3405 at mod.rs:418
    frame #42: 0x0000000101c1a2be servo`{{inlined-root}}::process_token<html5ever::tree_builder::TreeBuilder<script::dom::bindings::js::JS<script::dom::node::Node>, script::dom::servohtmlparser::Sink>>(self=0x000000011e642310, token=Token at 0x000000011d5f8b90) + 654 at mod.rs:233
    frame #43: 0x0000000101c1b0ca servo`{{inlined-root}}::emit_current_tag<html5ever::tree_builder::TreeBuilder<script::dom::bindings::js::JS<script::dom::node::Node>, script::dom::servohtmlparser::Sink>>(self=0x000000011e642310) + 1162 at mod.rs:392
    frame #44: 0x0000000101c20fdb servo`{{inlined-root}}::step<html5ever::tree_builder::TreeBuilder<script::dom::bindings::js::JS<script::dom::node::Node>, script::dom::servohtmlparser::Sink>>(self=0x000000011e642310) + 15867 at mod.rs:795
    frame #45: 0x0000000101c1cf94 servo`{{inlined-root}}::run<html5ever::tree_builder::TreeBuilder<script::dom::bindings::js::JS<script::dom::node::Node>, script::dom::servohtmlparser::Sink>>(self=0x000000011e642310) + 628 at mod.rs:334
    frame #46: 0x0000000101c1d14d servo`{{inlined-root}}::feed<html5ever::tree_builder::TreeBuilder<script::dom::bindings::js::JS<script::dom::node::Node>, script::dom::servohtmlparser::Sink>>(self=0x000000011e642310, input=Tendril<tendril::fmt::UTF8, tendril::tendril::NonAtomic> at 0x000000011d5fa9a8) + 413 at mod.rs:221
    frame #47: 0x00000001023c9c18 servo`script::dom::servohtmlparser::{{impl}}::do_parse_sync(self=0x000000011e642300) + 504 at servohtmlparser.rs:363
    frame #48: 0x00000001024a7d08 servo`script::dom::servohtmlparser::{{impl}}::parse_sync::{{closure}} + 40 at servohtmlparser.rs:352
    frame #49: 0x000000010135dc10 servo`{{inlined-root}}::profile<(category=ScriptParseHTML, meta=Option<profile_traits::time::TimerMetadata> at 0x000000011d5fac08, profiler_chan=ProfilerChan at 0x000000011d5fac00, callback=closure at 0x000000011d5fabf0),closure> + 176 at time.rs:108
    frame #50: 0x00000001023c99f7 servo`script::dom::servohtmlparser::{{impl}}::parse_sync(self=0x000000011e642300) + 423 at servohtmlparser.rs:349
    frame #51: 0x00000001023c82d3 servo`script::dom::servohtmlparser::{{impl}}::parse_chunk(self=0x000000011e642300, input=String at 0x000000011d5fadd8) + 371 at servohtmlparser.rs:237
    frame #52: 0x000000010244ae7c servo`script::parse::{{impl}}::parse_chunk(self=0x000000011d5faf40, input=String at 0x000000011d5fae98) + 172 at mod.rs:109
    frame #53: 0x00000001023c74ff servo`script::dom::servohtmlparser::{{impl}}::data_available(self=0x000000011e63b020, payload=Vec<u8> at 0x000000011d5fb008) + 639 at servohtmlparser.rs:177
    frame #54: 0x0000000101d2bd50 servo`{{inlined-root}}::process<script::dom::servohtmlparser::ParserContext>(self=ResponseAction at 0x000000011d5fb300, listener=0x000000011e63b020) + 352 at lib.rs:261
    frame #55: 0x00000001024446bb servo`script::network_listener::{{impl}}::handler<net_traits::ResponseAction,script::dom::servohtmlparser::ParserContext>(self=0x0000000119a15700) + 459 at network_listener.rs:71
    frame #56: 0x000000010245a7ff servo`script::script_thread::{{impl}}::handle_msg_from_script(self=0x000000011d5ff318, msg=MainThreadScriptMsg at 0x000000011d5fbb08) + 1327 at script_thread.rs:954
    frame #57: 0x00000001024a77f5 servo`script::script_thread::{{impl}}::handle_msgs::{{closure}} + 405 at script_thread.rs:786
    frame #58: 0x00000001024589e6 servo`script::script_thread::{{impl}}::profile_event<closure,core::option::Option<bool>>(self=0x000000011d5ff318, category=NetworkEvent, f=closure at 0x000000011d5fc490) + 1062 at script_thread.rs:880
    frame #59: 0x0000000102457744 servo`script::script_thread::{{impl}}::handle_msgs(self=0x000000011d5ff318) + 7396 at script_thread.rs:778
    frame #60: 0x0000000102455a4d servo`script::script_thread::{{impl}}::start(self=0x000000011d5ff318) + 29 at script_thread.rs:632
    frame #61: 0x00000001024a662c servo`script::script_thread::{{impl}}::create::{{closure}}::{{closure}} + 44 at script_thread.rs:474
    frame #62: 0x000000010135c882 servo`{{inlined-root}}::run_with_memory_reporting<closure,fn(self=0x000000011d5ff560, f=closure at 0x000000011d5fed60, reporter_name=String at 0x000000011d5fed40, channel_for_reporter=Sender<script::script_thread::MainThreadScriptMsg> at 0x000000011d5fed28, msg=0x0000000000000020) -> script::script_runtime::CommonScriptMsg,script::script_runtime::CommonScriptMsg,std::sync::mpsc::Sender<script::script_thread::MainThreadScriptMsg>> + 690 at mem.rs:59
    frame #63: 0x00000001027995c4 servo`script::script_thread::{{impl}}::create::{{closure}} + 1764 at script_thread.rs:473
    frame #64: 0x0000000101e16768 servo`{{inlined-root}}::call_once<(self=AssertUnwindSafe<closure> at 0x000000011d5ff848, _args=<unavailable>),closure> + 136 at panic.rs:256
    frame #65: 0x00000001025abc2c servo`std::panicking::try::_$u7b$$u7b$closure$u7d$$u7d$::_$u7b$$u7b$closure$u7d$$u7d$::ha95a03972526c7f7 + 92
    frame #66: 0x000000010172db45 servo`{{inlined-root}}::call<closure>(f=0x000000011d5fff58) + 21 at panicking.rs:272
    frame #67: 0x0000000104b7d71b servo`__rust_maybe_catch_panic + 27
    frame #68: 0x00000001025abb7e servo`std::panicking::try::_$u7b$$u7b$closure$u7d$$u7d$::he9a51e1f1d836034 + 158
    frame #69: 0x000000010179f910 servo`{{inlined-root}}::with<core::cell::Cell<usize>,closure,core::result::Result<(self=0x00000001060b9760, f=closure at 0x000000011d5ffff8), Box<Any>>> + 208 at local.rs:245
    frame #70: 0x00000001016c6480 servo`{{inlined-root}}::try<(f=AssertUnwindSafe<closure> at 0x000000011d6002b8),std::panic::AssertUnwindSafe<closure>> + 192 at panicking.rs:235
    frame #71: 0x000000010160352f servo`{{inlined-root}}::catch_unwind<std::panic::AssertUnwindSafe<closure>,(f=AssertUnwindSafe<closure> at 0x000000011d600718)> + 143 at panic.rs:312
    frame #72: 0x00000001024c867d servo`std::thread::Builder::spawn::_$u7b$$u7b$closure$u7d$$u7d$::h4b7df7e534520368 + 349
    frame #73: 0x0000000101bf58f8 servo`{{inlined-root}}::call_box<(self=0x000000011bc57000, args=<unavailable>),closure> + 104 at boxed.rs:587
    frame #74: 0x0000000104b7b4a9 servo`std::sys::thread::Thread::new::thread_start::h8f3bd45211e9f5ea + 57
    frame #75: 0x00007fff945f2899 libsystem_pthread.dylib`_pthread_body + 138
    frame #76: 0x00007fff945f272a libsystem_pthread.dylib`_pthread_start + 137
    frame #77: 0x00007fff945f6fc9 libsystem_pthread.dylib`thread_start + 13

[Ms2ger]

The buggy code is

    // https://html.spec.whatwg.org/multipage/#dom-link-rel
    make_setter!(SetRel, "rel");

in htmllinkelement.rs. It should be more like

    // https://dom.spec.whatwg.org/#dom-element-classname
    fn SetClassName(&self, class: DOMString) {
        self.set_tokenlist_attribute(&atom!("class"), class);
    }

[highfive]

Please make a comment here if you intend to work on this issue. Thank you!

[cynicaldevil]

@Ms2ger What about this method here?

[KiChjang]

@cynicaldevil The make_setter macro expands and defines the SetRel function that you linked.

[cynicaldevil]

@KiChjang yeah I thought about that after I wrote that comment....anyway, how am I supposed to do this? I looked up SetClassName and found that it belonged to the ElementMethods trait, which currently is not being implemented by htmlLinkElement.

[jdm]

@cynicaldevil HTMLLinkElement "inherits" from Element, so you can call some_link_element.upcast::<Element>() and then invoke methods from ElementMethods.

[jdm]

See http://doc.servo.org/script/dom/index.html#inheritance for a better explanation.

[KiChjang]

@cynicaldevil I'm going to assume that you're currently working on this.

[cynicaldevil]

@KiChjang yes, that's right.
@jdm Thanks, I will look into it.

[KiChjang]

@cynicaldevil Any problems so far? Any blockers, questions?

[cynicaldevil]

@KiChjang I'm sorry I completely forgot about this, I will take a look and get back to you if I have any questions in a day or two :)