From 1f996185e15b56e287e46992e14a33da95c9bab8 Mon Sep 17 00:00:00 2001
From: Ethan Atkins <ethan.atkins@gmail.com>
Date: Sat, 6 Oct 2018 11:39:05 -0700
Subject: [PATCH] Only use a file repository for interactive sessions

I realized that using the cache has the potential to cause issues for
batch processing in CI if some tasks assume that a file created by one
task will immediately be visible in the other. With the cache, there is
typically on O(10ms) latency between a file being created and appearing
in the cache (at least on OSX). When manually running commands, that
latency doesn't matter.
---
 main/src/main/scala/sbt/Defaults.scala                |  6 ++----
 main/src/main/scala/sbt/internal/FileManagement.scala | 10 ++++++++--
 2 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/main/src/main/scala/sbt/Defaults.scala b/main/src/main/scala/sbt/Defaults.scala
index 212d02442..2c4bf38e3 100755
--- a/main/src/main/scala/sbt/Defaults.scala
+++ b/main/src/main/scala/sbt/Defaults.scala
@@ -272,8 +272,7 @@ object Defaults extends BuildCommon {
         None
       },
       watchStartMessage := Watched.defaultStartWatch,
-      fileTreeViewConfig := FileTreeViewConfig
-        .default(watchAntiEntropy.value, pollInterval.value, pollingDirectories.value),
+      fileTreeViewConfig := FileManagement.defaultFileTreeView.value,
       fileTreeView := state.value
         .get(BasicKeys.globalFileTreeView)
         .getOrElse(FileTreeView.DEFAULT.asDataView(StampedFile.converter)),
@@ -657,8 +656,7 @@ object Defaults extends BuildCommon {
     },
     watchStartMessage := Watched.projectOnWatchMessage(thisProjectRef.value.project),
     watch := watchSetting.value,
-    fileTreeViewConfig := FileTreeViewConfig
-      .default(watchAntiEntropy.value, pollInterval.value, pollingDirectories.value)
+    fileTreeViewConfig := FileManagement.defaultFileTreeView.value
   )
 
   def generate(generators: SettingKey[Seq[Task[Seq[File]]]]): Initialize[Task[Seq[File]]] =
diff --git a/main/src/main/scala/sbt/internal/FileManagement.scala b/main/src/main/scala/sbt/internal/FileManagement.scala
index bbdbb346c..127fd4a1d 100644
--- a/main/src/main/scala/sbt/internal/FileManagement.scala
+++ b/main/src/main/scala/sbt/internal/FileManagement.scala
@@ -13,10 +13,16 @@ import java.nio.file.Path
 import sbt.Keys._
 import sbt.io.FileTreeDataView.Entry
 import sbt.io.syntax.File
-import sbt.io.{ FileFilter, FileTreeRepository, FileTreeDataView }
-import sbt.{ Def, ScopedTaskable, StampedFile, Task }
+import sbt.io.{ FileFilter, FileTreeDataView, FileTreeRepository }
+import sbt._
 
 private[sbt] object FileManagement {
+  private[sbt] def defaultFileTreeView: Def.Initialize[Task[FileTreeViewConfig]] = Def.task {
+    if (state.value.remainingCommands.exists(_.commandLine == "shell")) {
+      FileTreeViewConfig
+        .default(watchAntiEntropy.value, pollInterval.value, pollingDirectories.value)
+    } else FileTreeViewConfig.sbt1_2_compat(pollInterval.value, watchAntiEntropy.value)
+  }
   private[sbt] implicit class FileTreeDataViewOps[+T](val fileTreeDataView: FileTreeDataView[T]) {
     def register(path: Path, maxDepth: Int): Either[IOException, Boolean] = {
       fileTreeDataView match {