Make offline installer optional

CONTRIBUTING.md

@@ -2,7 +2,7 @@ Steps to publish
 ================
 
 ```
-$ sbt -Dsbt.build.version=1.0.0-M1
+$ sbt -Dsbt.build.version=1.0.0-M1 -Dsbt.build.offline=true
 > universal:publish
 > debian:publish
 > rpm:publish

build.sbt

@@ -3,6 +3,12 @@ import _root_.bintray.InternalBintrayKeys._
 import _root_.bintray.{BintrayRepo, Bintray}
 import NativePackagerHelper._
 
+lazy val sbtOfflineInstall =
+  sys.props.getOrElse("sbt.build.offline", sys.env.getOrElse("sbt.build.offline", "false")) match {
+    case "true" => true
+    case "1"    => true
+    case _      => false
+  }
 lazy val sbtVersionToRelease = sys.props.getOrElse("sbt.build.version", sys.env.getOrElse("sbt.build.version", {
         sys.error("-Dsbt.build.version must be set")
       }))
@@ -119,10 +125,14 @@ val root = (project in file(".")).
       val rtExportJar = (packageBin in Compile in java9rtexport).value
       Seq(launchJar -> "bin/sbt-launch.jar", rtExportJar -> "bin/java9-rt-export.jar")
     },
-    mappings in Universal ++= {
-      val _ = (exportRepo in dist).value
-      directory((target in dist).value / "lib")
-    },
+    mappings in Universal ++= (Def.taskDyn {
+      if (sbtOfflineInstall)
+        Def.task {
+          val _ = (exportRepo in dist).value
+          directory((target in dist).value / "lib")
+        }
+      else Def.task { Seq[(File, String)]() }
+    }).value,
     stage in Universal := {
       val old = (stage in Universal).value
       val sd = (stagingDirectory in Universal).value

src/universal/bin/sbt-launch-lib.bash

@@ -159,9 +159,12 @@ process_args () {
 
 syncPreloaded() {
   [[ -f "$HOME/.sbt/preloaded/org.scala-sbt/sbt/$init_sbt_version/jars/sbt.jar" ]] || {
-    command -v rsync >/dev/null 2>&1 && {
-      mkdir -p "$HOME/.sbt/preloaded"
-      rsync -a --ignore-existing "$sbt_home/lib/local-preloaded/" "$HOME/.sbt/preloaded"
+    # lib/local-preloaded exists (This is optional)
+    [[ -f "$sbt_home/lib/local-preloaded/" ]] && {
+      command -v rsync >/dev/null 2>&1 && {
+        mkdir -p "$HOME/.sbt/preloaded"
+        rsync -a --ignore-existing "$sbt_home/lib/local-preloaded/" "$HOME/.sbt/preloaded"
+      }
     }
   }
 }

src/universal/bin/sbt.bat

@@ -149,8 +149,10 @@ if /I "%JAVA_VERSION%" GEQ "8" (
   if %ERRORLEVEL% equ 0 (
     echo %PRELOAD_SBT_JAR%
     if not exist %PRELOAD_SBT_JAR% (
-      echo 'about to robocopy'
-      robocopy "%SBT_HOME%\..\lib\local-preloaded\" "%UserProfile%\.sbt\preloaded"
+      if exist "%SBT_HOME%\..\lib\local-preloaded\" (
+        echo 'about to robocopy'
+        robocopy "%SBT_HOME%\..\lib\local-preloaded\" "%UserProfile%\.sbt\preloaded"
+      )
     )
   )
 )