static js module encode issue when oneof objects.

[ehallander9591]

protobuf.js version: <6.5.0>

In the generated Static Module code, complex oneof components are initialized to null, but the discriminator getter function checks against undefined

syntax = "proto3";

package test;

message SomeContent {
	string someString = 1;
}

message SomeOtherContent {
	uint32 someInt = 1;
    string someString = 2;
}

message TestMessage {
	string someId = 1;
    oneof oneOrTheOther {
	    SomeContent someContent = 2;
	    SomeOtherContent someOtherContent = 3;
	}
}

The create for TestMessage shows

        test.TestMessage = (function() {
    
            /**
             * Constructs a new TestMessage.
             * @exports test.TestMessage
             * @constructor
             * @param {Object} [properties] Properties to set
             */
            function TestMessage(properties) {
                if (properties) {
                    var keys = Object.keys(properties);
                    for (var i = 0; i < keys.length; ++i)
                        this[keys[i]] = properties[keys[i]];
                }
            }
    
            /** @alias test.TestMessage.prototype */
            var $prototype = TestMessage.prototype;
    
            /**
             * TestMessage someId.
             * @type {string}
             */
            $prototype.someId = "";
    
            /**
             * TestMessage someContent.
             * @type {test.SomeContent}
             */
            $prototype.someContent = null;
    
            /**
             * TestMessage someOtherContent.
             * @type {test.SomeOtherContent}
             */
            $prototype.someOtherContent = null;
    

and when encode does a switch on message.oneOrTheOther
it triggers this

            Object.defineProperty($prototype, "oneOrTheOther", {
                get: function() {
                    if (this["someContent"] !== undefined)
                        return "someContent";
                    if (this["someOtherContent"] !== undefined)
                        return "someOtherContent";
                    return undefined;
                },

<please paste the stack trace of the error if applicable>

[ehallander9591]

I should have finished the statement. If I set someOtherContent and then try to encode the TestMessage, the above get will return "someContent" because $prototype.someContent == null which !== undefined, and then a nice stack trace will get issued when SomeContent.encode is called with a null object.

Cheers

[dcodeIO]

Hmm, I'd even go a bit further and say that also everything with a default value on the prototype other than undefined leads to incorrect return values. Will probably even be necessary to port what's used for reflection to static code.

[dcodeIO]

This now re-uses some common runtime utility derived from reflection within static code (example output). Let me know if there are any issues!

[ehallander9591]

That is a working solution.

Thanks

Since my oneof block was all complex messages, it wasn't until I was driving home that I thought about how that code was going to work for primitives

Cheers