Autocomplete hint widget doesn't show up in remote case.

I am experimenting with CM’s autocomplete feature. I am having an issue in such a scenario: when a dot (’.’) is typed after an object, I trigger the autocomplete process which calls ‘someurl’ to return the completion results from the server, in async mode; then call the callback to pass the data to CM once the request returns. I expect the hint widget (the list of completion results) to show up immediately. However, the hint widget doesn’t show, until I enter some letter (like ‘a’).

My code is like below:

        CodeMirror.registerHelper('hint', 'ajax', (mirror, callback) => {
            var cur = mirror.getCursor();
            var range = mirror.findWordAt(cur);

            callServer('someurl', function() {
                    list: ['a', 'b'],
                    from: range.anchor,
                    to: range.head
        CodeMirror.hint.ajax.async = true;

        CodeMirror.commands.autocomplete = function(mirror) {
                hint: CodeMirror.hint.ajax

        myCodeMirror.on("keyup", function (cm, event) {
            if (!cm.state.completionActive &&   /*Enables keyboard navigation in autocomplete list*/
                 event.keyCode == 190) { // when key is .
                     CodeMirror.commands.autocomplete(cm, null, {completeSingle: true});

The issue seems to have something to do with the aync part of code – if I return {list,from,to} in CodeMirror.hint.ajax sync and comment out this line:

        CodeMirror.hint.ajax.async = true;

the hint widget containing ‘a’ and ‘b’ shows up immediately.

How can I have the hint widget show up immediately for async results?


Any idea what’s happening here? or anything I can do to provide more information on this issue? :grinning: