feature request: `bulloak check --fix <file>` to automatically update a test file where the spec changed

[mds1]

This is a half-baked idea, but the thinking is:

• I write a .tree file and bulloak -w <file>
• I edit my .tree file, now my test is out of date
• I have to have generate new solidity with bulloak and manually move things

I'm picturing a bulloak check --fix or bulloak update command that, if I only added or moved lines in the tree, regenerates my test file with the code properly moved also. If lines were also changed, perhaps what it can do is something like this:

contract MyTest is Test {
  function test_123() {
    // bulloak automatically scaffolded everything and populated what it could
  }

  // <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
  // ======== BULLOAK AUTOGENERATED SEPARATOR ========
  // >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
  // Code below this section could not be automatically moved by bulloak and must be manually moved.

  function test_456() {
    // bulloak never deletes your code so it places it here
  }
}

[alexfertel]

Yes, this definitely improves DX. I need to give it some thought because I'm not that happy with the current bulloak -wf flow, and this change would surely influence that part of the API.

[alexfertel]

Well, this is a bit harder than I anticipated because a few things I need from solang_parser are missing. I'll see if there is a solidity parser I can use, otherwise, I'll write one.

[alexfertel]

Ok, ended up using solang_parser but patched a few things on top, leveraging forge-fmt. This commit is a good foundation for this feature.

You can try it out with bulloak check --fix --stdout and let me know what you think!