version-dependent source directories for sbt in npm SemVer range syntax
projectdir/src/main/scala<2.13/will be used for scala versions below 2.13.0projectdir/src/main/scala>=2.13/will be used for scala versions 2.13.0 and laterprojectdir/src/main/scala^2.13.2/will be used for scala 2.13.2 <= version < 3.0.0projectdir/src/main/scala>=3.0.0-M2 <3.0.0-RC/will be used for all dotty milestone releases after 2 (but not RCs)projectdir/src/main/scala^2.13.2 || ~2.12.13/will be used for scala 2.13.2 <= version < 3.0.0 and 2.12.13 <= version < 2.13
Connoisseurs may recognize the last pattern as the version range in which the scala reporter changed to allow warning suppression.
Put the following in project/plugins.sbt:
addSbtPlugin("com.heroestools" %% "sbt-sourcedirs" % "1.0.0")and that's all.
If your normal scala directory is in project/src/main/scala, then sbt automatically makes projectdir/src/main/scala-2.12 and projectdir/scr/main/scala-2.13 available for version-specific code.
This plugin adds semver ranges to the mix. Any directory scala$range or scala-$range where range is an npm-style semver range as described in https://docs.npmjs.com/cli/v6/using-npm/semver#ranges will be used if the scala version matches the range.
The most common usage is having scala<=2.12 and scala>=2.13 to have one directory
for everything below 2.13.0, and one for 2.13 and the 3 series.
The plugin exposes the boolean setting sourcedirsMatchPrereleases, which, by default
is true, so that scala>=2.13 also matches the milestone and RC releases of
upcoming versions (e.g. scala 3.0.0-M3).
You can set it to false if you don't want to match prerelease tags unless they're explicitly part of the range.
Example
sourcedirsMatchPrereleases := false
//now projectdir/src/main/scala>2.13.0 will no longer match scala 3.0.0-RC1Creating new directories after loading your project in sbt doesn't automatically add them until you reload the project.