Angular 11 --prod build of `@arcgis/core` application fails to render `Legend` in an `Expand` and `FeatureLayer` symbology

I am reporting an issue with

• TypeScript definitions
• [ x ] another resource in this repository

Issue

I’m using @arcgis/core 4.18.1 Beta in an Angular 11 application. It’s a simple application that I’m trying to use as the basis for a blog post about integrating ng components into the DefaultUI.

When using the development server (ng serve) or a “non-prod” build (ng build), the application works as expected. When adding the --prod flag to the ng build command, the feature layer renders, but the Legend widget fails and the symbology is not as-defined on the layer.

Replication

Here’s a repository that can be used to replicate the issue: https://github.com/vitale232/ngx-widget-post

The issue is present in both branches. To test the builds, I’m using the lite-server from npm.

npm install -g lite-server

To see how the application should look and function, run the following:

ng build
lite-server --baseDir dist/ngx-widget

To replicate the issue, run

ng build --prod
lite-server --baseDir dist/ngx-widget

The build runs fine, but the served output is not as expected:

There are some warnings present in the console:

Secondary Issue

I’m not sure if ya’ll intend to support this, but I also tried to build this application in a stackblitz. The blitz is a bit slow to compile, but when it does, the map does not render.

https://stackblitz.com/edit/ngx-widget-esri-core

Aside from this, the ESM build has been a joy to work with. Exciting times for Esri JS devs!

[andygup]

Thanks for reporting @vitale232! We are investigating a number of issues related to Angular production builds and the information you have provided is very helpful.

I’ll also take a look at stackblitz, not sure what’s going on there.

[andygup]

do you expect the bundle size to come down as the ESM build matures, or is it more of a WYSIWG proposition for now

We’ll continue to optimize while at the same time we are adding new functionality. It’s a balance of both.

FYI, we’re hoping to have the build error issue resolved at 4.19 (April). Since this is a known problem that we are actively working on. I’ll go ahead and close this issue. Thanks again for reporting!