Compute PackageValidationBaselineVersion with MinVer?

[sliekens]

Hi,

I've been successfully using both MinVer (fantastic tool btw) and .NET Package Validation to check for breaking changes when running dotnet pack.

  <PropertyGroup>
    <EnablePackageValidation>true</EnablePackageValidation>
    <PackageValidationBaselineVersion>1.0.0</PackageValidationBaselineVersion>
  </PropertyGroup>

I've been manually updating the PackageValidationBaselineVersion property after each release, but I just realized I always just want to keep this in sync with the last package version.

Currently, MinVer sets $(Version) and $(PackageVersion), but I think I would need something like $(PreviousPackageVersion) to automate this.

  <PropertyGroup>
    <EnablePackageValidation>true</EnablePackageValidation>
    <PackageValidationBaselineVersion>$(PreviousPackageVersion)</PackageValidationBaselineVersion>
  </PropertyGroup>

Wouldn't it be possible to make this a computed property using MinVer build tasks?

[adamralph]

The main problem that computing that property presents is that the console apps (both the one used internally by the MinVer MSBuild task and the minver-cli dotnet tool) currently return a single string value—the version. They have no facility to return structured data consisting of more than a single literal, e.g a version and a previous version, and I'm not sure I want to introduce that complexity.

Another way to do this would be to write a custom target to make MinVer run in the context of the commit prior to the current commit, store the value of MinVerVersion, and then allow MinVer to run as it currently does to get the version of the current commit.

Pseudo-code:

<Target Name="MyTarget" BeforeTargets="MinVer">
  If there is a commit prior to the current commit
    git checkout HEAD^
    set MinVerIgnoreHeight to true
    run the MinVer target
    set MinVerIgnoreHeight to false
    git checkout @{-1}
    store the value of MinVerVersion in MinVerVersionPrevious    
</Target>

This assume you are currently not setting MinVerIgnoreHeight to true for determining the current version of your package. If you are, then this will be more complex. Maybe something like:

<Target Name="MyTarget" BeforeTargets="MinVer">
  If there is a commit prior to the current commit
    store the current commit sha
    If MinVerIgnoreHeight is true
        run the MinVer target
        git checkout MinVerVersion
    else
       git checkout HEAD^
    store the original value of MinVerIgnoreHeight
    set MinVerIgnoreHeight to true
    run the MinVer target
    set MinVerIgnoreHeight to the original value
    git checkout {original commit sha}
    store the value of MinVerVersion in MinVerVersionPrevious    
</Target>

You may also have to do something to cater for the edge case of not having any tag in the commit history.