Reduce memory consumption

[julienrf]

Creating chains of settings was consuming an exponential amount of memory. This did not scale when used with builds with dozens of modules.

By using dynamic settings, the chain of dependencies is not kept, resulting in less memory consumption.

[adpi2]

Oh that's a nice bug!

Have you tried with join rather than foldLeft?

Something like this maybe (I didn't try to compile it):

      val modules: Seq[Setting[(String, String)]]] = allProjectRefs.map { case (projectRef, _) =>
          Def.setting {
            val projectOrganization       = (projectRef / organization).value
            val projectName               = (projectRef / moduleName).value
            val projectVersion            = (projectRef / version).value
            val projectCrossVersion       = (projectRef / crossVersion).value
            val projectScalaVersion       = (projectRef / scalaVersion).value
            val projectScalaBinaryVersion = (projectRef / scalaBinaryVersion).value
            if (versionRegex.findFirstMatchIn(projectVersion).isDefined) {
              val nameWithBinarySuffix =
                CrossVersion(projectCrossVersion, projectScalaVersion, projectScalaBinaryVersion)
                  .fold(projectName)(_(projectName))
              Some(projectOrganization -> nameWithBinarySuffix)
            } else {
              // Don’t include the module if its version does not match the regex
              None
            }
          }
        }
    modules.join.map(_.flatten.toSet)

[julienrf]

Interesting, I didn’t know about join. Your code does not compile, but I could use Def.uniform instead (which is a generalization of join, AFAIU), and it works fine. Are there any benefits of doing that instead of what I have in the PR?

[adpi2]

It feels more idiomatic to me. At least you don't need those settingDyn that are hard to understand and that could be removed by mistake.