webpack-issues

This repository reproduces some issues I've been having with Webpack getting correct paths in stack traces and hitting breakpoints. Specifically, this documents issues I reported in this Webpack issue.

Getting Started

Clone this repository to a local folder, and in that folder, do the following:

npm install
npm run build-dev
npm run build-dev-2
npm run build-dev-3
npm run build-dev-4

This builds the repository 4 times, with just a couple differences in the Webpack configuration for source map generation. All four configurations use webpack.SourceMapDevToolPlugin for source map generation. Here is what is interesting about each of the 4 configurations:

• dev - The devtool option is not present in the exported Webpack configuration object
• dev-2 - The Webpack config contains devtool: false
• dev-3 - The devtool option is not present, plus source-map-support is installed via webpack.BannerPlugin.
• dev-4 - The Webpck config contains devtool: false, plus source-map-support is installed via webpack.BannerPlugin.

Running the Tests

Run one of the configurations using the supplied npm scripts.

npm run dev

OR

npm run dev-2

etc.

Once it's running, fire up your favorite browser and surf http://localhost:3000/fail.

Then, look at the stack trace in either the browser or the console where the application is running and look at the first line of the stack trace.

Windows

On Windows, here is what I get from each of the configurations:

• dev
  This configuration produces the correct path to the original source file:

      at eval (c:\jmpdev\usr\sasewh\git\webpack-issues\src\server\routes\index.js:13:8)
  

• dev-2
  This configuration points into the bundle rather than to the original source code:

      at c:\jmpdev\usr\sasewh\git\webpack-issues\build\bundle-server-dev-2.js:569:8
  

• dev-3
  This configuration also produces the correct path to the original source file:

      at eval (c:\jmpdev\usr\sasewh\git\webpack-issues\src\server\routes\index.js:13:8)
  

• dev-4
  This configuration is trying to point to the line in the original source file, but with source-map-support involved, the path ends up with webpack:\ in the middle of it:

      at c:\jmpdev\usr\sasewh\git\webpack-issues\build\webpack:\src\server\routes\index.js:13:1
  

Mac

And here is what I get from each configuration on the Mac, none of which are any good:

• dev
  In the "close but no cigar" category, with this configuration I get:

      at eval (Users/sasewh/Development/git/webpack-issues/src/server/routes/index.js:13:8)
      at Layer.handle [as handle_request] (/Users/sasewh/Development/git/webpack-issues/node_modules/express/lib/router/layer.js:95:5)
  

  I included two lines of the stack trace here. Notice that in the first line, the leading slash on the path is missing. This is true for all non-external lines of code. The second line is external, which has the correct path, because it's not source-mapped.
• dev-2
  Like in the Windows case, with devtool: false in the config file, source-mapping seems to not happen, so we get a perfectly fine path into the bundle, which does us no good:

      at /Users/sasewh/Development/git/webpack-issues/build/bundle-server-dev-2.js:569:8
  

• dev-3
  Same result as dev:

      at eval (Users/sasewh/Development/git/webpack-issues/src/server/routes/index.js:13:8)
  

• dev-4
  This one is also agonizingly close. If I could just get the "build/webpack:" out of there:

      at /Users/sasewh/Development/git/webpack-issues/build/webpack:/src/server/routes/index.js:13:1
  

Production Builds

If I change the mode option from development to production and change nothing else, call stacks point into the bundle rather than to original source code. I thought source maps were supposed to work the same in production and development, but you just don't ship your source maps in production?