Migrate DevTools to use pub workspaces

[kenzieschmoll]

This will be a good way for us to dogfood the pub workspaces feature and find any devexp / devtools related bugs (like DevTools extensions or IDE integrations).

The workspace pubspec.yaml should likely live at the root of devtools/packages.

[kenzieschmoll]

I pushed up a draft for this at #8549, but something does not seem to working properly. I followed instructions and examples as closely as possible, but I'm not quite sure what is going wrong.

Running dart pub get from the top-level devtools/ directory succeeds, but the Problems view in VS code shows 54k+ problems. I have tried restarting the analysis server and the IDE, but I still have analysis issues all over my project. I am opening the root devtools/ directory in VS Code.

Also, here is the output from running dart pub workspace list:

Package              Path                           
_                    ./                             
devtools_app         packages/devtools_app/         
devtools_app_shared  packages/devtools_app_shared/  
devtools_extensions  packages/devtools_extensions/  
devtools_shared      packages/devtools_shared/      
devtools_test        packages/devtools_test/        
devtools_tool        tool/   

CC @sigurdm - any ideas? Also CC @DanTup in case there could be something going wrong with my local VS Code configuration.

[sigurdm]

I believe I found the issue.

On the main branch you have a packages/pubspec.yaml file, (which results in a corresponding packages/.dart_tool/package_config.json.

On the PR branch there is no packages/pubspec.yaml, but when the branch is switched packages/.dart_tool/package_config.json remains, because it is .gitignored.

This file is the cause of all the trouble, because the analyzer picks that one up when it traverses directories towards the root.

pub get will remove existing .dart_tool/package_config.json in any workspace project folder, but not in the interim folders.

The workaround is to run rm packages/.dart_tool/package_config.json from the repository root.

We should probably update pub to delete .dart_tool/package_config.json from all interim folders in the workspace.
@jonasfj WDYT?

[sigurdm]

A fix to delete those files is proposed in https://github.com/dart-lang/pub/pull/4446/files

[kenzieschmoll]

@sigurdm thanks for looking into this. That fixed my local setup and I think the fix you pushed up to prevent other users from hitting this will be great.

The next issue I am hitting is with build_runner. We generate mocks as part of our CI setup, and this is now failing with the move to use workspaces:

Running build_runner build for devtools_app...
/home/runner/work/devtools/devtools/packages/devtools_app > /home/runner/work/devtools/devtools/tool/flutter-sdk/bin/flutter pub run build_runner build --delete-conflicting-outputs
Package "build_runner" is not an immediate dependency.
Cannot run executables in transitive dependencies.
Failed to update packages.
ProcessException: Failed with exit code: 65. 
  Command: /home/runner/work/devtools/devtools/tool/flutter-sdk/bin/flutter pub run build_runner build --delete-conflicting-outputs

build_runner is still listed as a dependency in devtools_app/pubspec.yaml but it appears that the system thinks that it is a "transitive dependency".

[kenzieschmoll]

Nevermind I got this passing by adding the build_runner dep to the top level pubspec.yaml file.