如何调试从 CoffeeScript 生成的 Node.js/JavaScript 代码？

Question

I'm using CoffeeScript with Node.js. I want to be able to debug JavaScript errors/exceptions that pop up, but the line numbers for those errors are from the generated JavaScript code, not from the CoffeeScript source, so I'm having trouble figuring out where in the CoffeeScript the error actually is.

Is there anyway I can debug this? I have the latest version of node.js, version 0.10 .

Answer 1

The CoffeeScript compiler supports source maps , so there is a mapping from JavaScript to Coffeescript with the information you need to know. For your server-side project I think that Jet Brains uses this map for debugging . On the browser side Chrome seems to support it . I'm not sure if one of the tools works for you, but if not I think CoffeeScript and source map are the words you should look for. Good luck!

Answer 2

I created a tool for LiveScript, which works very close to CoffeeScript so you can modify it according to your needs: https://github.com/ceremcem/debug-ls

Briefly:

• Use your favourite bundler (I use Rollup in this case) to generate one bundle with sourcemaps from your main script.

• Run your script with the following command:

   node --enable-source-maps --inspect-brk your-bundle.js

• Go to chrome://inspect/#devices address in Chrome

• Find your process that is listed under "Remote Target" section

• Click "inspect" button

Answer 3

because sourcemap, coffee just like js. so we can debug coffee in vscode. anyway here is my launch.json:

{
    "version": "0.2.0",
    "configurations": [{
        "type": "node",
        "request": "launch",
        "name": "Launch Program",
        "skipFiles": [
            "<node_internals>/**"
        ],
        "program": "${file}", //important, make sure debug current file
        "outFiles": [
            "${workspaceFolder}/dist/api/api.js" //important, where to find sourcemap js file
        ]
    }]
}