Implement back publishing support

.github/workflows/ci.yml

@@ -13,4 +13,4 @@ jobs:
         java-version: 8
         cache: sbt
     - uses: sbt/setup-sbt@v1
-    - run: sbt +compile
+    - run: sbt +test

build.sbt

@@ -40,6 +40,7 @@ lazy val plugin = project
         case _      => "2.0.0-M2"
       }
     },
+    libraryDependencies += "org.scalameta" %% "munit" % "0.7.29" % Test,
     addSbtPlugin("com.github.sbt" % "sbt-dynver" % "5.1.0"),
     addSbtPlugin("com.github.sbt" % "sbt-git" % "2.1.0"),
     addSbtPlugin("com.github.sbt" % "sbt-pgp" % "2.3.0"),

plugin/src/main/scala/com/geirsson/CiReleasePlugin.scala

@@ -106,6 +106,8 @@ object CiReleasePlugin extends AutoPlugin {
       Some(s"scm:git:git@github.com:$user/$repo.git")
     )
 
+  lazy val cireleasePublishCommand = settingKey[String]("")
+
   override lazy val buildSettings: Seq[Def.Setting[_]] = List(
     dynverSonatypeSnapshots := true,
     scmInfo ~= {
@@ -128,15 +130,29 @@ object CiReleasePlugin extends AutoPlugin {
         } catch {
           case NonFatal(_) => None
         }
-    }
+    },
+    cireleasePublishCommand := {
+      val gitDescribe = dynverGitDescribeOutput.value
+      val v = gitDescribe.getVersion(
+        dynverCurrentDate.value,
+        dynverSeparator.value,
+        dynverSonatypeSnapshots.value
+      )
+      sys.env.get("CI_RELEASE") match {
+        case Some(cmd) => cmd
+        case None      => backPubVersionToCommand(v)
+      }
+    },
+    version ~= dropBackPubCommand,
   )
 
   override lazy val globalSettings: Seq[Def.Setting[_]] = List(
     (Test / publishArtifact) := false,
     publishMavenStyle := true,
     commands += Command.command("ci-release") { currentState =>
       val shouldDeployToSonatypeCentral = isDeploySetToSonatypeCentral(currentState)
-      val isSnapshot = isSnapshotVersion(currentState)
+      val version = getVersion(currentState)
+      val isSnapshot = isSnapshotVersion(version)
       if (!isSecure) {
         println("No access to secret variables, doing nothing")
         currentState
@@ -150,6 +166,8 @@ object CiReleasePlugin extends AutoPlugin {
         val reloadKeyFiles =
           "; set pgpSecretRing := pgpSecretRing.value; set pgpPublicRing := pgpPublicRing.value"
 
+        val publishCommand = getPublishCommand(currentState)
+
         if (shouldDeployToSonatypeCentral) {
           if (isSnapshot) {
             println(s"Sonatype Central does not accept snapshots, only official releases. Aborting release.")
@@ -161,7 +179,7 @@ object CiReleasePlugin extends AutoPlugin {
             println("Tag push detected, publishing a stable release")
             reloadKeyFiles ::
               sys.env.getOrElse("CI_CLEAN", "; clean ; sonatypeBundleClean") ::
-              sys.env.getOrElse("CI_RELEASE", "+publishSigned") ::
+              publishCommand ::
               sys.env.getOrElse("CI_SONATYPE_RELEASE", "sonatypeCentralRelease") ::
               currentState
           }
@@ -184,7 +202,7 @@ object CiReleasePlugin extends AutoPlugin {
             println("Tag push detected, publishing a stable release")
             reloadKeyFiles ::
               sys.env.getOrElse("CI_CLEAN", "; clean ; sonatypeBundleClean") ::
-              sys.env.getOrElse("CI_RELEASE", "+publishSigned") ::
+              publishCommand ::
               sys.env.getOrElse("CI_SONATYPE_RELEASE", "sonatypeBundleRelease") ::
               currentState
           }
@@ -210,10 +228,49 @@ object CiReleasePlugin extends AutoPlugin {
     }
   }
 
-  def isSnapshotVersion(state: State): Boolean = {
+  def getVersion(state: State): String =
     (ThisBuild / version).get(Project.extract(state).structure.data) match {
-      case Some(v) => v.endsWith("-SNAPSHOT")
+      case Some(v) => v
       case None    => throw new NoSuchFieldError("version")
     }
+
+  def getPublishCommand(state: State): String =
+    (ThisBuild / cireleasePublishCommand).get(Project.extract(state).structure.data) match {
+      case Some(v) => v
+      case None    => throw new NoSuchFieldError("cireleasePublishCommand")
+    }
+
+  def isSnapshotVersion(v: String): Boolean = v.endsWith("-SNAPSHOT")
+
+  def backPubVersionToCommand(ver: String): String =
+    if (ver.contains("@")) {
+      val nonComment =
+        if (ver.contains("#")) ver.split("#").head
+        else ver
+      val commands0 = nonComment.split("@").toList.drop(1)
+      var nonDigit = false
+      val commands = (commands0.map { cmd =>
+        if (cmd.isEmpty) sys.error(s"Invalid back-publish version: $ver")
+        else {
+          if (!cmd.head.isDigit) {
+            nonDigit = true
+            cmd
+          }
+          else if (cmd.contains(".x")) s"++${cmd}"
+          else s"++${cmd}!"
+        }
+      }) ::: (if (nonDigit) Nil else List("publishSigned"))
+      commands match {
+        case x :: Nil => x
+        case xs       => xs.mkString(";", ";", "")
+      }
+    } else "+publishSigned"
+
+  def dropBackPubCommand(ver: String): String = {
+    val nonComment =
+      if (ver.contains("#")) ver.split("#").head
+      else ver
+    if (nonComment.contains("@")) nonComment.split("@").head
+    else nonComment
   }
 }

plugin/src/test/scala/com/geirsson/CiReleaseTest.scala

@@ -0,0 +1,47 @@
+package com.geirsson
+
+import CiReleasePlugin.{ backPubVersionToCommand, dropBackPubCommand }
+
+class CiReleaseTest extends munit.FunSuite {
+  val expectedVer = "1.1.0"
+
+  test("Normal version default") {
+    assertEquals(backPubVersionToCommand("1.1.0"), "+publishSigned")
+    assertEquals(dropBackPubCommand("1.1.0"), expectedVer)
+  }
+
+  test("Command starting with number is assumed to be a cross version") {
+    assertEquals(backPubVersionToCommand("1.1.0@2.12.20"), ";++2.12.20!;publishSigned")
+    assertEquals(dropBackPubCommand("1.1.0@2.12.20"), expectedVer)
+
+    assertEquals(backPubVersionToCommand("1.1.0@3.x"), ";++3.x;publishSigned")
+    assertEquals(dropBackPubCommand("1.1.0@3.x"), expectedVer)
+  }
+
+  test("Non-number is treated as an alternative publish command") {
+    assertEquals(backPubVersionToCommand("1.1.0@foo/publishSigned"), "foo/publishSigned")
+    assertEquals(dropBackPubCommand("1.1.0@foo/publishSigned"), expectedVer)
+
+    assertEquals(backPubVersionToCommand("1.1.0@+foo/publishSigned"), "+foo/publishSigned")
+    assertEquals(dropBackPubCommand("1.1.0@+foo/publishSigned"), expectedVer)
+  }
+
+  test("Commands can be chained") {
+    assertEquals(backPubVersionToCommand("1.1.0@2.12.20@foo/publishSigned"), ";++2.12.20!;foo/publishSigned")
+    assertEquals(dropBackPubCommand("1.1.0@2.12.20@foo/publishSigned"), expectedVer)
+
+    assertEquals(backPubVersionToCommand("1.1.0@foo/something@bar/publishSigned"), ";foo/something;bar/publishSigned")
+    assertEquals(dropBackPubCommand("1.1.0@foo/something@bar/publishSigned"), expectedVer)
+  }
+
+  test("Treat # as comments") {
+    assertEquals(backPubVersionToCommand("1.1.0#comment"), "+publishSigned")
+    assertEquals(dropBackPubCommand("1.1.0#comment"), expectedVer)
+
+    assertEquals(backPubVersionToCommand("1.1.0@2.12.20#comment"), ";++2.12.20!;publishSigned")
+    assertEquals(dropBackPubCommand("1.1.0@2.12.20#comment"), expectedVer)
+
+    assertEquals(backPubVersionToCommand("1.1.0@3.x#comment"), ";++3.x;publishSigned")
+    assertEquals(dropBackPubCommand("1.1.0@3.x#comment"), expectedVer)
+  }
+}

readme.md

@@ -356,6 +356,56 @@ page will look like this:
 
 Enjoy 👌
 
+### Back-publishing support
+
+sbt-ci-release implements a mini-DSL for the Git tag for back publishing purpose, which is useful if you maintain a compiler plugin, library for Scala Native, or an sbt plugin during 2.x migration etc.
+
+```
+v1.2.3[@3.x|@2.n.x|@a.b.c][@command][#comment]
+```
+
+- `#` is used for comments, which is useful if you need to use the same command multiple times
+- `@3.x` expands to `++3.x`, and if no other commands follow, `;++3.x;publishSigned`
+- `@2.13.x` expands to `++2.13.x`, and if no other commands follow, `;++2.13.x;publishSigned`
+- Other commands such as `@foo/publishSigned` expands to `foo/publishSigned`
+
+#### Case 1: Publish all subprojects for Scala 2.13.15
+
+`v1.2.3@2.13.15`
+
+#### Case 2: Publish all subprojects for Scala 3.x
+
+`v1.2.3@3.x`. Optionally we can add a comment: `v1.2.3@3.x#comment`.
+
+We can use this to back publish sbt 2.x plugins.
+
+1. Branch off of `v1.2.3` to create `release/1.2.3` branch, and send a PR to update sbt version
+2. Tag the brach to `v1.2.3@3.x#sbt2.0.0-Mn`
+
+#### Case 3: Publish some subprojects for Scala 2.13.15
+
+`v1.2.3@2.13.15@foo/publishSigned`
+
+You can create a subproject to aggregate 2 or more subprojects.
+
+#### Case 4: Publish some subprojects for supported Scala versions
+
+`v1.2.3@+foo_native/publishSigned#comment`
+
+1. Branch off of `v1.2.3` to create `release/1.2.3` branch, and send a PR to update the Scala Native version.
+2. Tag the branch to `v1.2.3@+foo_native/publishSigned#native0.5`
+
+#### Case 5: Minimize the use of command
+
+`v1.2.3#unique_comment`, for example `v1.2.3#native0.5_3`
+
+If you prefer to keep most of the information in a git branch instead, you can just use the comment functionality.
+
+1. Branch off of `v1.2.3` to create `release/1.2.3` branch, and send a PR to:
+   a. Update appropriate dependency (sbt, Scala Native etc)
+   b. Modify the `CI_RELEASE` environment variable to encode the actions you want to take, like `;++3.x;foo_native/publishSigned`. For GitHub Actions, it would be in `.github/workflows/release.yml`
+2. Tag the branch to `v1.2.3#unique_comment`. For record keeping, encode the version you're trying to back publishing for e.g. `v1.2.3#native0.5_3`
+
 ## FAQ
 
 ### How do I publish to Sonatype Central?