Make default baseline the previous stable version in the registry

[epage]

With just cargo semver-checks in package directory, it should take the current version and select the previous one. For pre-release versions, it should select the previous non-pre-release as breaking changes between prereleases is fine.

[obi1kenobi]

For other folks reading this issue: this logic is already implemented in the GitHub Action that runs cargo-semver-checks.

This issue is about moving some of that functionality into cargo-semver-checks itself to make it easier to run the tool directly via the CLI, as opposed to running it as a GitHub Action.

[epage]

Is the action correctly handling pre-release? imo the default should not select a previous pre-release but the previous stable release

[obi1kenobi]

Good question. Agreed on the desired behavior. Have not tested it but I'd guess it would pick pre-releases like so:

• 1.2.3-alpha.1 would compare to 1.2.2
• 1.2.3-alpha.2 would compare to 1.2.3-alpha.1
• 1.2.3 would compare to 1.2.3-alpha.2

I believe this produces an equivalent result because semver-checking is transitive: if all those transitions are individually valid then 1.2.3 compared to 1.2.2 is valid too. But probably still worth changing when moving the logic into cargo-semver-checks itself.

[epage]

Expected result

• 1.2.3-alpha.1 should compare to 1.2.2
• 1.2.3-alpha.2 should compare to 1.2.2
• 1.2.3 should compare to 1.2.2

Unfortunately, it is not transitive for pre-release because you are allow to make breaking changes between pre-release versions.

[epage]

#92 fixed some related pre-release issues