feature: export the correct js file in npm

[BernhardRode]

When installing mapbox-gl via npm and importing the library like:

import * as mapboxgl from 'mapbox-gl';

The npm resolver is looking for tha main attribute in package.json to further resolve the correct JavaScript file for import.

fixes #3551

[lucaswoj]

Our docs suggest using import mapboxgl from 'mapbox-gl/dist/mapbox-gl'; to import this module into Webpack.

That said, I’m leaning towards 👍 on this. It’d make require(‘mapbox-gl’) work in more cases. The only downside I can think of is if someone wants to npm link and see their changes instantly. That ought to be a pretty rare use case for GL JS since the monorepo.

Any thoughts @jfirebaugh?

@BernhardRode You'll need to fix the CI build & ensure npm publish still works.

[jfirebaugh]

@mourner suggested this in #3551 and I'm in favor. Let's do it.

[mourner]

👍 Let's fix the CI build, then merge.

[lucaswoj]

CI fix:

diff --git a/package.json b/package.json
index c5b97fc..88338ee 100644
--- a/package.json
+++ b/package.json
@@ -113,7 +113,7 @@
     "build": "npm run build-docs # invoked by publisher when publishing docs on the mb-pages branch",
     "start-docs": "npm run build-min && npm run build-docs && jekyll serve --watch",
     "lint": "eslint --ignore-path .gitignore src test bench docs/_posts/examples/*.html debug/*.html",
-    "lint-docs": "documentation lint",
+    "lint-docs": "documentation lint src/index.js",
     "open-changed-examples": "git diff --name-only mb-pages HEAD -- docs/_posts/examples/*.html | awk '{print \"http://127.0.0.1:4000/mapbox-gl-js/example/\" substr($0,33,length($0)-37)}' | xargs open",
     "test": "run-s lint test-unit test-flow",
     "test-suite": "run-s test-render test-query",