Support Dart language.

[LinArcX]

Hi. Thank you for this great effort. It's awesome to add Dart language support to vimspector. Is it possible at all?

[puremourning]

Is there a dart debug adapter?

[LinArcX]

I know in this plugin, they use dart debug adapter:
https://github.com/Dart-Code/Dart-Code
But i don't know is it a seperate module or coupled with that plugin.

[puremourning]

https://github.com/Dart-Code/Dart-Code/blob/master/package.json#L955

That's where the debug plugin definition is found. It should be possible to make a .vimspector.json to work with it.

I haven't tried it but something like this might work:

{
  "adapters" {
      "dart-code": {
        "name": "dart",
        "command": [
           "node",
           "$HOME/.vscode/<PATH TO BUNDLE>/src/debug/dart_debug_entry.js"
        ],
        "attach": {
          "pidProperty": "observatoryUri",
          "pidSelect": "ask"
        }
      }
  },
  "configurations": {
    "Dart - Launch": {
      "adapter": "dart-code",
      "configuration": {
        "request": "launch",
        "cwd": "string",
        "deviceId": "string",
        "enableAsserts": "boolean",
        "program": "string",
        "showMemoryUsage": "boolean",
        "flutterMode": "enum [ debug, release, profile ]",
        "args": "array[string]",
        "env": " ?? ",
        "vmAdditionalArgs": "array[string]"
      }
    },
    "Dart - Attach": {
      "adapter": "dart-code",
      "configuration": {
        "request": "attach",
        "cwd": "string",
        "packages": "string"
      }
    }
  }

Obviously, fill in the actual values and PATH_TO_BUNDLE, etc.

Let me know how you get on. I have found that I often have to read the vscode plugin code to work out the actual set of arguments required by the adapter, but once vimspector starts the adapter and initialises it successfully, it tends to work.

~/.vimspector.log is very useful in debugging these configs too.

Feel free to ask on Gitter for assistance.

[puremourning]

The dart adapter should be workable with something like the above config. I'm not likely to add official support for it unless there's a really strong need

[LinArcX]

OK, i started to actually debug a simple dart app.
After following this tutorial and generated a binary file, i created this .vimspector and put it in root of my project:

{
  "adapters": {
      "dart-code": {
        "name": "dart",
        "command": [
           "node",
           "$HOME/.vscode-oss/extensions/dart-code.dart-code-3.8.0/src/debug/dart_debug_entry.js"
        ],
        "attach": {
          "pidProperty": "observatoryUri",
          "pidSelect": "ask"
        }
      }
  },
  "configurations": {
    "Dart - Launch": {
      "adapter": "dart-code",
      "configuration": {
        "request": "launch",
        "cwd": "${workspaceRoot}",
        "program": "${workspaceRoot}/bin/myapp"
      }
    },
    "Dart - Attach": {
      "adapter": "dart-code",
      "configuration": {
        "request": "attach",
        "cwd": "${workspaceRoot}"
      }
    }
  }
}

But it gives me these errors:
https://gist.github.com/LinArcX/b797a27cdc0015dadb406156b8216a18

Edit 1: I didn't cloned Dart-Code repo. Instead installed vscode and through it, installed dart plugin.

Edit 2: I've noticed that there isn't any dart_debug_entry.js Dart-Code.(Is it the root of evil?)

[puremourning]

So it looks like the visual studio extension uses webpack which obviously vimspector can't use.

Also even if you can get around that (I did by building from source), the debug adapter requires vscode and does not work outside of it, due to a design-o:

Error: Cannot find module 'vscode'
Require stack:
- /Users/ben/Development/vimspector/Dart-Code/out/src/extension/config.js
- /Users/ben/Development/vimspector/Dart-Code/out/src/debug/dart_debug_impl.js
- /Users/ben/Development/vimspector/Dart-Code/out/src/debug/dart_debug_entry.js
    at Function.Module._resolveFilename (internal/modules/cjs/loader.js:966:17)
    at Function.Module._load (internal/modules/cjs/loader.js:859:27)
    at Module.require (internal/modules/cjs/loader.js:1028:19)
    at require (internal/modules/cjs/helpers.js:72:18)
    at Object.<anonymous> (/Users/ben/Development/vimspector/Dart-Code/out/src/extension/config.js:12:18)
    at Module._compile (internal/modules/cjs/loader.js:1139:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:1159:10)
    at Module.load (internal/modules/cjs/loader.js:988:32)
    at Function.Module._load (internal/modules/cjs/loader.js:896:14)
    at Module.require (internal/modules/cjs/loader.js:1028:19) {
  code: 'MODULE_NOT_FOUND',
  requireStack: [
    '/Users/ben/Development/vimspector/Dart-Code/out/src/extension/config.js',
    '/Users/ben/Development/vimspector/Dart-Code/out/src/debug/dart_debug_impl.js',
    '/Users/ben/Development/vimspector/Dart-Code/out/src/debug/dart_debug_entry.js'
  ]
}

So basically the dart debug adapter that's embedded in Dart-Code cannot be used standalone, so IMO should not be listed on the DAP implementations page. Feel free to raise a bug with them to make it standalone (it should be possible, it's only their config module that seems to require vscode, which I assume means the DA doesn't actually require it).

[puremourning]

If you want to replicate my testing:

• clone the Dart-Code repo
• npm install
• npm run build-tests
• check out the minimal project in support/test/dart/cli in this branch of vimspector, in particular this vimspector.json:

{
  "adapters": {
    "dart-code": {
      "variables": {
        "root": "/Users/ben/Development/vimspector/Dart-Code"
      },
      "type": "dart",
      "command": [
        "node",
        "${root}/out/src/debug/dart_debug_entry.js"
      ],
      "configuration": {
        "console": "terminal"
      }
    }
  },
  "configurations": {
    "Launch": {
      "adapter": "dart-code",
      "configuration": {
        "request": "launch",
        "type": "dart",
        "program": "${file}"
      }
    }
  }
}

obviously adjust root variable accordingly, but it still won't work.

[puremourning]

In fact, you already know this. Because it was pointed out to you here, right. https://www.reddit.com/r/vim/comments/ahyf9a/debug_adapter_protocoldap_plugin_for_vim/

I am talking about the DART debug adapter from https://github.com/Dart-Code/Dart-Code . I have contacted the author and he mentioned that the debug adapter could run only in VSCode since it has a runtime dependency on it.

So yeah, dart can't work with vimspector unless someone else write a debug adapter that is independent of vscode.

[LinArcX]

@puremourning As @DanTup said, I've tired latest commit of Dart-Code with your instructions.

But i've got this error message:

Unable to restart debugging. Please try ending the debug session and starting again.

I don't know if this issue related to Dart-Code or vimspector. If related to Dart-Code let me know to report to @DanTup.

[puremourning]

It's unlikely to be vimspector saying that. And you didn't post any diagnostics, so i can't decide one way or the other, but reading @DanTup's latest comment, i guess it's not quite there yet.