[Bug Tracking] LSP (VS Code)

[ankitaS11]

This issue will contain discussions and bug tracking around LSP support for VSCode.

[certik]

TODO:

• fix bugs (sometimes it doesn't seem to update / clean error messages when saved)
• the symbol table gets duplicated
• Implement symbol lookup (F12)
• add tests (add a Python script that launches "lpython lsp ..." and sends JSON to it, and checks that a correct JSON gets returned)
• document in README how to test the LSP (how to compile the extension and test it out in Debug mode)
• polish the extension, move it under lcompilers/lpython_vscode_extension (or something like that), and publish on VSCode marketplace
• Figure out how to make it work "automatically", without the need to save (?)
• Add a "Debug" button, that would expose all AST and ASR nodes in the "Outline", which would be helpful for Debugging and ensuring the AST and ASR is correct; in fact we can even expose the ASR and Python source code (?) after each ASR pass, so that we can visually ensure that it is correct (this would be very helpful for developing ASR passes such as optimizations)
• Add a "Run" button that would compile and run the current file

[certik]

Here is the current state:

• Errors get highlighted (when you save with Ctrl-S)
• The file symbols (from ASR) get shown in the Outline