Merge pull request #3071 from eed3si9n/fport/3014

[fport] Check for regular file in Package.makeJar

main-actions/src/main/scala/sbt/Package.scala

@@ -94,8 +94,13 @@ object Package {
       ManifestAttributes((attribKeys zip attribVals) ++ { homepage map (h => (IMPLEMENTATION_URL, h.toString)) }: _*)
     }
   def makeJar(sources: Seq[(File, String)], jar: File, manifest: Manifest, log: Logger): Unit = {
-    log.info("Packaging " + jar.getAbsolutePath + " ...")
-    IO.delete(jar)
+    val path = jar.getAbsolutePath
+    log.info("Packaging " + path + " ...")
+    if (jar.exists)
+      if (jar.isFile)
+        IO.delete(jar)
+      else
+        sys.error(path + " exists, but is not a regular file")
     log.debug(sourcesDebugString(sources))
     IO.jar(sources, jar, manifest)
     log.info("Done packaging.")

sbt/src/sbt-test/actions/package-delete-target/build.sbt

@@ -0,0 +1,5 @@
+lazy val root = (project in file("."))
+  .settings(
+    name := "delete-target",
+    scalaVersion := "2.12.1"
+  )

sbt/src/sbt-test/actions/package-delete-target/test

@@ -0,0 +1,4 @@
+$ mkdir target/scala-2.12/delete-target_2.12-0.1-SNAPSHOT.jar
+$ touch target/scala-2.12/delete-target_2.12-0.1-SNAPSHOT.jar/hello
+-> package
+$ exists target/scala-2.12/delete-target_2.12-0.1-SNAPSHOT.jar/hello