[2.x] feat: Add setup-java action support in CrossJava (#8574)

Add SetupJavaDiscoverConfig to detect JDKs installed by GitHub's
setup-java action at paths like:
- /opt/hostedtoolcache/Java_Zulu_jdk/25.0.1-8/x64 (Linux)
- C:\hostedtoolcache\windows\Java_Temurin-Hotspot_jdk\11.0.29-7\x64 (Windows)

These JDKs are now available in fullJavaHomes as zulu@25.0.1,
temurin@11.0.29, etc.

Supported vendors: Zulu, Temurin, Adopt, Corretto, Liberica,
Microsoft, Semeru. Temurin-Hotspot and Adopt are normalized to
temurin.

Fixes #8582

* test: Refactor setup-java tests to use real directory structure

---------

Co-authored-by: mkdev11 <noreply@users.noreply.github.com>

main/src/main/scala/sbt/internal/CrossJava.scala

@@ -484,17 +484,53 @@ private[sbt] object CrossJava {
           .toVector
     }
 
+    class SetupJavaDiscoverConfig(base: File) extends JavaDiscoverConf {
+      private val SetupJavaVendorDir =
+        """Java_(Zulu|Temurin-Hotspot|Temurin|Adopt|Corretto|Liberica|Microsoft|Semeru)_jdk""".r
+      private val SetupJavaVersionDir = """([0-9]+)\.([0-9]+)\.([0-9]+)(-[0-9]+)?""".r
+
+      private def normalizeVendor(vendor: String): String = vendor.toLowerCase match {
+        case "temurin-hotspot" => "temurin"
+        case "adopt"           => "temurin"
+        case other             => other
+      }
+
+      def candidates(): Vector[String] = wrapNull(base.list())
+
+      def javaHomes: Vector[(String, File)] =
+        candidates().flatMap {
+          case vendorDir @ SetupJavaVendorDir(vendor) =>
+            val vendorPath = base / vendorDir
+            wrapNull(vendorPath.list()).flatMap {
+              case versionDir @ SetupJavaVersionDir(major, minor, patch, _) =>
+                val versionPath = vendorPath / versionDir
+                val archDirs = wrapNull(versionPath.list())
+                archDirs.headOption.map { arch =>
+                  val javaHome = versionPath / arch
+                  val normalizedVendor = normalizeVendor(vendor)
+                  val version = s"$major.$minor.$patch"
+                  val jv = JavaVersion(version).withVendor(normalizedVendor)
+                  jv.toString -> javaHome
+                }
+              case _ => None
+            }
+          case _ => Vector.empty
+        }
+    }
+
     val configs = Vector(
       new JabbaDiscoverConfig,
       new SdkmanDiscoverConfig,
       new LinuxDiscoverConfig(file("/usr") / "java"),
       new LinuxDiscoverConfig(file("/usr") / "lib" / "jvm"),
+      new SetupJavaDiscoverConfig(file("/opt") / "hostedtoolcache"),
       new MacOsDiscoverConfig,
       new JavaHomeDiscoverConfig,
     ) ++ {
       if (IO.isWindows) {
         def discover(dir: String, vendors: String*) = new WindowsDiscoverConfig(file(dir), vendors)
         Vector(
+          new SetupJavaDiscoverConfig(file("C:") / "hostedtoolcache" / "windows"),
           discover("C://Program Files/Java", "openjdk"),
           discover("C://Program Files/Eclipse Foundation", "temurin", "adopt"),
           discover("C://Program Files/Semeru", "semeru", "adopt-openj9"),

main/src/test/scala/sbt/internal/CrossJavaTest.scala

@@ -9,9 +9,12 @@
 package sbt
 package internal
 
+import java.io.File
 import org.scalatest.diagrams.Diagrams
 import org.scalatest.funsuite.AnyFunSuite
 import sbt.internal.CrossJava.JavaDiscoverConfig.*
+import sbt.io.{ IO, syntax }
+import sbt.io.syntax.*
 import scala.collection.immutable.ListMap
 
 class CrossJavaTest extends AnyFunSuite with Diagrams {
@@ -193,4 +196,50 @@ class CrossJavaTest extends AnyFunSuite with Diagrams {
       )
     )
   }
+
+  test("The setup-java selector should correctly pick up Zulu JDK") {
+    IO.withTemporaryDirectory { temp =>
+      IO.createDirectory(temp / "Java_Zulu_jdk" / "25.0.1-8" / "x64")
+      val conf = new SetupJavaDiscoverConfig(temp)
+      val homes = conf.javaHomes
+      assert(homes.size == 1)
+      val (version, javaHome) = homes.head
+      assert(version == "zulu@25.0.1")
+      assert(javaHome.getName == "x64")
+    }
+  }
+
+  test("The setup-java selector should correctly pick up Temurin JDK") {
+    IO.withTemporaryDirectory { temp =>
+      IO.createDirectory(temp / "Java_Temurin-Hotspot_jdk" / "11.0.29-7" / "x64")
+      val conf = new SetupJavaDiscoverConfig(temp)
+      val homes = conf.javaHomes
+      assert(homes.size == 1)
+      val (version, javaHome) = homes.head
+      assert(version == "temurin@11.0.29")
+      assert(javaHome.getName == "x64")
+    }
+  }
+
+  test("The setup-java selector should normalize Temurin-Hotspot to temurin") {
+    IO.withTemporaryDirectory { temp =>
+      IO.createDirectory(temp / "Java_Temurin-Hotspot_jdk" / "17.0.5-8" / "x64")
+      val conf = new SetupJavaDiscoverConfig(temp)
+      val homes = conf.javaHomes
+      assert(homes.size == 1)
+      val (version, _) = homes.head
+      assert(version == "temurin@17.0.5")
+    }
+  }
+
+  test("The setup-java selector should normalize Adopt to temurin") {
+    IO.withTemporaryDirectory { temp =>
+      IO.createDirectory(temp / "Java_Adopt_jdk" / "11.0.15-10" / "x64")
+      val conf = new SetupJavaDiscoverConfig(temp)
+      val homes = conf.javaHomes
+      assert(homes.size == 1)
+      val (version, _) = homes.head
+      assert(version == "temurin@11.0.15")
+    }
+  }
 }