From efec7bce31714ca048b7d4c3198ce63ff914f41b Mon Sep 17 00:00:00 2001
From: Ethan Atkins <contact@ethanatkins.com>
Date: Tue, 13 Oct 2020 08:17:21 -0700
Subject: [PATCH] Check if target is directory before creating

When project/target is a symbolic link, sbt 1.4.0 crashes on startup
because Files.createDirectories will throw a FileAlreadyExistsException.
The fix is to first check if the target directory exists before trying
to create it.
---
 main-command/src/main/java/sbt/internal/BootServerSocket.java | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/main-command/src/main/java/sbt/internal/BootServerSocket.java b/main-command/src/main/java/sbt/internal/BootServerSocket.java
index 3cda9e830..afae5c6f6 100644
--- a/main-command/src/main/java/sbt/internal/BootServerSocket.java
+++ b/main-command/src/main/java/sbt/internal/BootServerSocket.java
@@ -287,8 +287,8 @@ public class BootServerSocket implements AutoCloseable {
     final Path base = configuration.baseDirectory().toPath().toRealPath();
     final Path target = base.resolve("project").resolve("target");
     if (!isWindows) {
+      if (!Files.isDirectory(target)) Files.createDirectories(target);
       socketFile = Paths.get(socketLocation(base));
-      Files.createDirectories(target);
     } else {
       socketFile = null;
     }