Add scripted to test the sbt plugin resolution

As of sbt 1.9, we publish deprecated and valid poms. In this test
we check that sbt resolve the valid pom of an sbt plugin and fallback
to the deprecated pom if the valid pom cannot be found.

sbt-app/src/sbt-test/dependency-management/sbt-plugin-diamond/build.sbt

@@ -0,0 +1,105 @@
+// sbt-plugin-example-diamond is a diamond graph of dependencies of sbt plugins.
+//             sbt-plugin-example-diamond
+//                        / \
+// sbt-plugin-example-left   sbt-plugin-example-right
+//                        \ /
+//             sbt-plugin-example-bottom
+// Depending on the version of sbt-plugin-example-diamond, we test different patterns
+// of dependencies:
+//  * Some dependencies were published using the deprecated Maven paths, some with the new
+//  * Wheter the dependency on sbt-plugin-example-bottom needs conflict resolution or not
+
+inThisBuild(
+  Seq(
+    csrCacheDirectory := baseDirectory.value / "coursier-cache"
+  )
+)
+
+// only deprecated Maven paths
+lazy val v1 = project
+  .in(file("v1"))
+  .settings(
+    localCache,
+    addSbtPlugin("ch.epfl.scala" % "sbt-plugin-example-diamond" % "0.1.0"),
+    checkUpdate := checkUpdateDef(
+      "sbt-plugin-example-diamond-0.1.0.jar",
+      "sbt-plugin-example-left-0.1.0.jar",
+      "sbt-plugin-example-right-0.1.0.jar",
+      "sbt-plugin-example-bottom-0.1.0.jar",
+    ).value
+  )
+
+// diamond and left use the new Maven paths
+lazy val v2 = project
+  .in(file("v2"))
+  .settings(
+    localCache,
+    addSbtPlugin("ch.epfl.scala" % "sbt-plugin-example-diamond" % "0.2.0"),
+    checkUpdate := checkUpdateDef(
+      "sbt-plugin-example-diamond_2.12_1.0-0.2.0.jar",
+      "sbt-plugin-example-left_2.12_1.0-0.2.0.jar",
+      "sbt-plugin-example-right-0.1.0.jar",
+      "sbt-plugin-example-bottom-0.1.0.jar",
+    ).value
+  )
+
+// conflict resolution on bottom between new and deprecated Maven paths
+lazy val v3 = project
+  .in(file("v3"))
+  .settings(
+    localCache,
+    addSbtPlugin("ch.epfl.scala" % "sbt-plugin-example-diamond" % "0.3.0"),
+    checkUpdate := checkUpdateDef(
+      "sbt-plugin-example-diamond_2.12_1.0-0.3.0.jar",
+      "sbt-plugin-example-left_2.12_1.0-0.3.0.jar",
+      "sbt-plugin-example-right-0.1.0.jar",
+      "sbt-plugin-example-bottom_2.12_1.0-0.2.0.jar",
+    ).value
+  )
+
+// right still uses the deprecated Maven path and it depends on bottom
+// which uses the new Maven path
+lazy val v4 = project
+  .in(file("v4"))
+  .settings(
+    localCache,
+    addSbtPlugin("ch.epfl.scala" % "sbt-plugin-example-diamond" % "0.4.0"),
+    checkUpdate := checkUpdateDef(
+      "sbt-plugin-example-diamond_2.12_1.0-0.4.0.jar",
+      "sbt-plugin-example-left_2.12_1.0-0.3.0.jar",
+      "sbt-plugin-example-right-0.2.0.jar",
+      "sbt-plugin-example-bottom_2.12_1.0-0.2.0.jar",
+    ).value
+  )
+
+// only new Maven paths with conflict resolution on bottom
+lazy val v5 = project
+  .in(file("v5"))
+  .settings(
+    localCache,
+    addSbtPlugin("ch.epfl.scala" % "sbt-plugin-example-diamond" % "0.5.0"),
+    checkUpdate := checkUpdateDef(
+      "sbt-plugin-example-diamond_2.12_1.0-0.5.0.jar",
+      "sbt-plugin-example-left_2.12_1.0-0.3.0.jar",
+      "sbt-plugin-example-right_2.12_1.0-0.3.0.jar",
+      "sbt-plugin-example-bottom_2.12_1.0-0.3.0.jar",
+    ).value
+  )
+
+def localCache =
+  ivyPaths := IvyPaths(baseDirectory.value, Some((ThisBuild / baseDirectory).value / "ivy-cache"))
+
+lazy val checkUpdate = taskKey[Unit]("check the resolved artifacts")
+
+def checkUpdateDef(expected: String*): Def.Initialize[Task[Unit]] = Def.task {
+  val report = update.value
+  val obtainedFiles = report.configurations
+    .find(_.configuration.name == Compile.name)
+    .toSeq
+    .flatMap(_.modules)
+    .flatMap(_.artifacts)
+    .map(_._2)
+  val obtainedSet = obtainedFiles.map(_.getName).toSet
+  val expectedSet = expected.toSet + "scala-library.jar"
+  assert(obtainedSet == expectedSet, obtainedFiles)
+}

sbt-app/src/sbt-test/dependency-management/sbt-plugin-diamond/test

@@ -0,0 +1,12 @@
+> v1/checkUpdate
+> v2/checkUpdate
+> v3/checkUpdate
+> v4/checkUpdate
+> v5/checkUpdate
+
+> set ThisBuild/useCoursier:=true
+> v1/checkUpdate
+> v2/checkUpdate
+> v3/checkUpdate
+> v4/checkUpdate
+> v5/checkUpdate