Index documents on modification

[vinistock]

Motivation

Closes #1908

This PR starts indexing files upon modification in addition to on saves.

Implementation

The idea is to use the declaration listener together with all of the other listeners, so that we collect declaration changes within the same AST traversal. This allows us to catch any declaration modifications made before saving a file.

The biggest concern with this change is performance, but I think the next PR in this stack is doing a decent job at minimizing reindexes.

Automated Tests

Added tests.

[vinistock]

• Only reindex documents if declarations are being modified #2942
• Index documents on modification #2941 👈 (View in Graphite)
• main

This stack of pull requests is managed by Graphite. Learn more about stacking.

[andyw8]

Nice!

I did notice an issue while testing:

module Bar
  def abc
  end
end

class Foo
  extend Bar
end

Foo.abc

If you remove the extend, Foo will still offer completion with abc, even after saving. (On main it works correctly).

[vinistock]

@andyw8 good catch. I updated the code to handle ancestor invalidation too.