Merge pull request #6276 from fommil/emacs

GNU Emacs support for sbtn and sbt --client

.gitignore

@@ -10,4 +10,5 @@ npm-debug.log
 .idea
 .bloop
 .metals
+.bsp/
 /project/metals.sbt

internal/util-collection/src/main/scala/sbt/internal/util/Util.scala

@@ -64,6 +64,8 @@ object Util {
   lazy val isNonCygwinWindows: Boolean = isWindows && !isCygwin
   lazy val isCygwinWindows: Boolean = isWindows && isCygwin
 
+  lazy val isEmacs: Boolean = Option(System.getenv("INSIDE_EMACS")).isDefined
+
   def nil[A]: List[A] = List.empty[A]
   def nilSeq[A]: Seq[A] = Seq.empty[A]
   def none[A]: Option[A] = (None: Option[A])

internal/util-logging/src/main/scala/sbt/internal/util/Terminal.scala

@@ -317,7 +317,10 @@ object Terminal {
     props
       .map(_.color)
       .orElse(isColorEnabledProp)
-      .getOrElse(logFormatEnabled.getOrElse(true) && ((hasConsole && !isDumbTerminal) || isCI))
+      .getOrElse(
+        logFormatEnabled
+          .getOrElse(true) && ((hasConsole && !isDumbTerminal) || isCI || Util.isEmacs)
+      )
   }
   private[this] lazy val isColorEnabledProp: Option[Boolean] =
     sys.props.get("sbt.color").orElse(sys.props.get("sbt.colour")).flatMap(parseLogOption)
@@ -867,7 +870,8 @@ object Terminal {
         .map(_.supershell)
         .getOrElse(System.getProperty("sbt.supershell") match {
           case null =>
-            !(sys.env.contains("BUILD_NUMBER") || sys.env.contains("CI")) && isColorEnabled
+            !(sys.env.contains("BUILD_NUMBER") || sys.env
+              .contains("CI")) && isColorEnabled && !Util.isEmacs
           case "true" => true
           case _      => false
         })

main-command/src/main/scala/sbt/internal/client/NetworkClient.scala

@@ -337,8 +337,13 @@ class NetworkClient(
               List(DashDashDetachStdio, DashDashServer)
         }
 
+        // https://github.com/sbt/sbt/issues/6271
+        val nohup =
+          if (Util.isEmacs && !Util.isWindows) List("nohup")
+          else Nil
+
         val processBuilder =
-          new ProcessBuilder(cmd: _*)
+          new ProcessBuilder((nohup ++ cmd): _*)
             .directory(arguments.baseDirectory)
             .redirectInput(Redirect.PIPE)
         processBuilder.environment.put(Terminal.TERMINAL_PROPS, props)