From c53e229175e41c1cd3c81e9bb5014f493ee3f27e Mon Sep 17 00:00:00 2001
From: Hood Chatham <roberthoodchatham@gmail.com>
Date: Mon, 12 Sep 2022 17:00:54 -0500
Subject: [PATCH] Fix webpack warnings and reenable webpack test (#3094)

This uses sed to insert /* webpackIgnore: true */ comments into pyodide.js.
This resolves #3087. I also enabled a check that a simple webpack config
builds without warnings. In the future it would be good to add a test that it
also runs without error.
---
 .circleci/config.yml      | 16 ++++++++--------
 Makefile                  |  4 ++++
 docs/project/changelog.md |  5 +++++
 src/js/compat.ts          |  1 -
 4 files changed, 17 insertions(+), 9 deletions(-)

diff --git a/.circleci/config.yml b/.circleci/config.yml
index 639f64b28..d37991936 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -369,14 +369,14 @@ jobs:
             npm link ../../dist
             npm run test-types
             npm test
-      # - run:
-      #     name: check if webpack cli works well with load-pyodide.js
-      #     command: |
-      #       git clone https://github.com/pyodide/pyodide-webpack-example.git
-      #       cd pyodide-webpack-example
-      #       npm ci
-      #       cp ../src/js/*.js node_modules/pyodide/
-      #       npx webpack
+      - run:
+          name: check if Pyodide works with Webpack
+          command: |
+            git clone https://github.com/pyodide/pyodide-webpack-example.git
+            export DEV_PYODIDE_PATH=`realpath dist`
+            cd pyodide-webpack-example
+            git checkout 164054a9c6fbd2176f386b6552ed8d079c6bcc04
+            ./build.sh
 
   test-cmdline-runner:
     <<: *defaults
diff --git a/Makefile b/Makefile
index 28ee46187..f426eb243 100644
--- a/Makefile
+++ b/Makefile
@@ -74,6 +74,10 @@ node_modules/.installed : src/js/package.json src/js/package-lock.json
 
 dist/pyodide.js src/js/_pyodide.out.js: src/js/*.ts src/js/pyproxy.gen.ts src/js/error_handling.gen.ts node_modules/.installed
 	npx rollup -c src/js/rollup.config.js
+   # Add /* webpackIgnore: true */ to each dynamic import in `pyodide.js`.
+   # Rollup strips comments so this can't be done via the source file.
+   # We use ! as the sed separator because the replacement text includes /
+	sed -i 's!await import(!await import(/* webpackIgnore: true */ !g' dist/pyodide.js
 
 dist/package.json : src/js/package.json
 	cp $< $@
diff --git a/docs/project/changelog.md b/docs/project/changelog.md
index 1c868f94f..22d5ba5b9 100644
--- a/docs/project/changelog.md
+++ b/docs/project/changelog.md
@@ -58,6 +58,11 @@ substitutions:
 - {{ Fix }} Add `url` to list of pollyfilled packages for webpack compatibility.
   {pr}`3080`
 
+- {{ Fix }} Fixed warnings like
+  `Critical dependency: the request of a dependency is an expression.`
+  when using Pyodide with webpack.
+  {pr}`3080`
+
 - {{ Fix }} Source maps are included in the distribution again (reverting
   {pr}`3015` included in 0.21.2) and if there is a variable in top level scope
   called `__dirname` we use that for the `indexURL`.
diff --git a/src/js/compat.ts b/src/js/compat.ts
index c94fb1075..0fe8b65b1 100644
--- a/src/js/compat.ts
+++ b/src/js/compat.ts
@@ -182,7 +182,6 @@ if (globalThis.document) {
 } else if (globalThis.importScripts) {
   // webworker
   loadScript = async (url) => {
-    // This is async only for consistency
     try {
       // use importScripts in classic web worker
       globalThis.importScripts(url);