UnhandledPromiseRejectionWarning

eric-914 commented 6 years ago

I'm submitting a bug report

Library Version: 2.0.0-rc.5

Please tell us about your environment:

Operating System: Windows 10
Node Version: 8.9.0
NPM Version: 5.6.0
JSPM OR Webpack AND Version webpack 3.10.0
Browser: Chrome 62.0.3202.94
Language: TypeScript 2.6.2

Current behavior: When I run Webpack through gulp, I get the following message when my AureliaPlugin is included in webpack's config file:

(node:5920) UnhandledPromiseRejectionWarning: Unhandled promise rejection (rejection id: 1): TypeError: Cannot read property 'default' of undefined

It does not appear that AureliaPlugin has executed, as my output bundle is significantly smaller. This warning does not appear if I run Webpack directly.

Expected/desired behavior:

AureliaPlugin behavior should be consistent in either invocation.

Additional: My AureliaPlugin usage:

        new AureliaPlugin({
            dist: "native-modules",
            includeSubModules: [
                { moduleId: "aurelia-dialog" },
                { moduleId: "aurelia-validation" }
            ]
        })

My gulp task:

var gulp = require("gulp");
var webpack = require("webpack");

var config = require("../../webpack.dev.js");

gulp.task("webpack",
    (done) => {
        var onBuild =
            function(err, stats) {
                if (err) {
                    console.log(`Error: ${err}`);
                } else {
                    Object.keys(stats.compilation.assets).forEach(function(key) {
                        console.log(`Webpack: output ${key}`);
                    });
                }
            }

        webpack(config, onBuild);

        done();
    }
);

My invocation of webpack via gulp: npm run gulp webpack

I originally had this problem with another webpack plugin, but turns out I didn't need it. All remaining webpack plugins (5) do not have this warning.

jods4 commented 6 years ago

Before any further action: your invocation of done is clearly incorrect. It should happen when the task completes, i.e. inside onBuild.

eric-914 commented 6 years ago

Yeah, I noticed that as well the next day. It didn't change anything regarding this issue though. This isn't high priority to me, I've moved on to stop using the gulp steps. But I thought it still should be noted that it occurs.

jods4 commented 6 years ago

I don't have time to debug this, as long as Webpack CLI works it's not a critical issue... Not sure why the Webpack JS API would behave any different.

The error Cannot read property 'default' of undefined smells like a import X from "abc" that failed to resolve properly.

Alexander-Taran commented 6 years ago

@eric-914 have you tried it with webpack4 and new version of plugin? I don't see a way that plugin would be called differently. If you look at CLI source - it calls webpack directly. Your gulp task probably tries to do the same.

You can compare how it's implemented and figure out where mismatch is.