Missing return value from `makeMessageContextForTarget`.

[pyericz]

The following makeMessageContextForTarget method in engine/runtime.js has no return value.

    /**
     * Create a context ("args") object for use with `formatMessage` on messages which might be target-specific.
     * @param {Target} [target] - the target to use as context. If a target is not provided, default to the current
     * editing target or the stage.
     */
    makeMessageContextForTarget (target) {
        const context = {};
        target = target || this.getEditingTarget() || this.getTargetForStage();
        if (target) {
            context.targetType = (target.isStage ? TargetType.STAGE : TargetType.SPRITE);
        }
    }

The context should be returned. Here is a fixed version

    /**
     * Create a context ("args") object for use with `formatMessage` on messages which might be target-specific.
     * @param {Target} [target] - the target to use as context. If a target is not provided, default to the current
     * editing target or the stage.
     * @returns {object} - the context object.
     */
    makeMessageContextForTarget (target) {
        const context = {};
        target = target || this.getEditingTarget() || this.getTargetForStage();
        if (target) {
            context.targetType = (target.isStage ? TargetType.STAGE : TargetType.SPRITE);
        }
        return context;
    }

[BryceLTaylor]

@pyericz can you describe what a user experiences when this issue is encountered?

[pyericz]

@pyericz can you describe what a user experiences when this issue is encountered?

Well, I think that depends on how to design an extension. The context is used for making target-specific message, which means that your extension has to be target-specific. Besides, the context is usable only in maybeFormatMessage function, where the first parameter maybeMessage has to be an object which contains id and default fields. All of those strict restrictions make it hard to produce a specific issue or user experience of an extension. However, this is just a purely logic bug. You want to create a context that may be used in target-specific message, but you never return that context, and that will cause problems.