Default to sbtn for sbt 2.x

This changes the runner script logic to default to sbtn when sbt version is 2.x.

launcher-package/src/universal/bin/sbt.bat

@@ -890,22 +890,22 @@ for /F "delims=.-_ tokens=1-2" %%v in ("!sbtV!") do (
   set sbtBinaryV_1=%%v
   set sbtBinaryV_2=%%w
 )
-set native_client_ready=
+rem default to run_native_client=1 for sbt 2.x 
 if !sbtBinaryV_1! geq 2 (
-  set native_client_ready=1
+  if !sbt_args_client! equ 0 (
+    set run_native_client=
+  ) else (
+    set run_native_client=1
+  )
 ) else (
   if !sbtBinaryV_1! geq 1 (
     if !sbtBinaryV_2! geq 4 (
-      set native_client_ready=1
+      if !sbt_args_client! equ 1 (
+        set run_native_client=1
+      )
     )
   )
 )
-if !native_client_ready! equ 1 (
-  if !sbt_args_client! equ 1 (
-    set run_native_client=1
-  )
-)
-set native_client_ready=
 
 exit /B 0
 

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

@@ -1127,6 +1127,7 @@ object NetworkClient {
         sbtArguments += s"-Dsbt.script=$sbtScript"
       }
     }
+    if (!sbtArguments.contains("--server")) sbtArguments += "--server"
     new Arguments(
       base,
       sbtArguments.toSeq,

sbt

@@ -749,7 +749,14 @@ isRunNativeClient() {
   [[ "$sbtV" == "" ]] && sbtV="0.0.0"
   sbtBinaryV_1=$(echo "$sbtV" | sed 's/^\([0-9]*\)\.\([0-9]*\).*$/\1/')
   sbtBinaryV_2=$(echo "$sbtV" | sed 's/^\([0-9]*\)\.\([0-9]*\).*$/\2/')
-  if (( $sbtBinaryV_1 >= 2 )) || ( (( $sbtBinaryV_1 >= 1 )) && (( $sbtBinaryV_2 >= 4 )) ); then
+  # Default to true for sbt 2.x
+  if (( $sbtBinaryV_1 >= 2 )); then
+    if [[ "$use_sbtn" == "0" ]]; then
+      echo "false"
+    else
+      echo "true"
+    fi
+  elif ( (( $sbtBinaryV_1 >= 1 )) && (( $sbtBinaryV_2 >= 4 )) ); then
     if [[ "$use_sbtn" == "1" ]]; then
       echo "true"
     else