add flutter dependency detection

[mikeborodin]

Flutter dependency detection

As mentioned in #282 the we need a better way to detect which configs to use - Dart or Flutter. This PR intents to do that by matching the consequent lines in pubspec.yaml

Test cases I checked:

• Dart shelf example: has flutter = false
• Flutter counter example: has flutter = true
• Commented out 2 lines: has flutter = false
• Changed spacing (still valid yaml): has flutter = true
• Used tab instead of space: has flutter = true
• Removed lines: has flutter = false

[akinsho]

@sidlatau thoughts? I haven't really worked with any non flutter dart projects

[sidlatau]

@sidlatau thoughts? I haven't really worked with any non flutter dart projects

LGTM. We already have PR with similar logic https://github.com/akinsho/flutter-tools.nvim/pull/292/files - but it is easier to understand regex here than in mentioned PR.
Not sure which one is more performant and if that matters here.

[mikeborodin]

@sidlatau thoughts? I haven't really worked with any non flutter dart projects

LGTM. We already have PR with similar logic https://github.com/akinsho/flutter-tools.nvim/pull/292/files - but it is easier to understand regex here than in mentioned PR. Not sure which one is more performant and if that matters here.

Yes I saw that one but seems like there was no progress in some time and in my approach I intentionally don't keep the previous behavior.

[akinsho]

LGTM 👍🏾

[akinsho]

I imagine there might be some performance cost from using fn.glob and also fn.readfile as generally the fn.* methods do a trip through viml so are slower but I assume this function isn't called super often 🤷🏾‍♂️ we'll see