Fallback to closest Ruby if we can't find an installation for the requested version

[vinistock]

Motivation

Closes #2793

This PR starts adds a fallback for when the specified Ruby in .ruby-version is not found/not installed.

The UX is similar to the fallback for missing .ruby-version configurations. We show a temporary progress warning the user we're going to fallback and give the chance of cancelling, which allows them to manually configure the right version.

Implementation

The implementation is very similar to the fallback for missing .ruby-version. The main distinction is that, when we know the version specified, we can try to fallback to the closest one available.

There are a few decisions I baked into the implementation:

1. We do not try to approximate major versions. For example, if the .ruby-version file specifies Ruby 4.0.0, we would not try to fallback to 3.0.0. I think this is a fair limitation and since Ruby is so conservative about major versions, it shouldn't be too painful
2. To approximate, we search for the Ruby installation with the smallest difference in minor version using the highest patch version as the tie breaker (this is done with a sort). For example, if the requested version is 3.3.5 and we have 3.1.0 and 3.2.2 installed, we want to pick 3.2.2 because that's closest to 3.3.5. And as another example, if both 3.2.0 and 3.2.2 are installed, we would pick 3.2.2 because that's the highest patch

Automated Tests

Added tests.

[vinistock]

• Fallback to closest Ruby if we can't find an installation for the requested version #2912 👈 (View in Graphite)
• Extract Ruby fallback cancellable flow #2911
• main

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[vinistock]

Merge activity

• Nov 29, 10:39 AM EST: A user merged this pull request with Graphite.