diff --git a/main/src/test/scala/sbt/internal/LRUCacheTest.scala b/main/src/test/scala/sbt/internal/LRUCacheTest.scala
deleted file mode 100644
index 06add1271..000000000
--- a/main/src/test/scala/sbt/internal/LRUCacheTest.scala
+++ /dev/null
@@ -1,78 +0,0 @@
-/*
- * sbt
- * Copyright 2011 - 2018, Lightbend, Inc.
- * Copyright 2008 - 2010, Mark Harrah
- * Licensed under Apache License 2.0 (see LICENSE)
- */
-
-package sbt
-package internal
-
-import java.util.concurrent.atomic.AtomicInteger
-
-import org.scalatest.{ FlatSpec, Matchers }
-
-class LRUCacheTest extends FlatSpec with Matchers {
-  "LRUCache" should "flush entries when full" in {
-    val cache = LRUCache[Int, Int](2)
-    cache.put(1, 1)
-    cache.put(2, 2)
-    cache.put(3, 3)
-    assert(cache.get(1).isEmpty)
-    assert(cache.get(2).contains(2))
-    assert(cache.get(3).contains(3))
-
-    assert(cache.get(2).contains(2))
-    cache.put(1, 1)
-    assert(cache.get(3).isEmpty)
-    assert(cache.get(2).contains(2))
-    assert(cache.get(1).contains(1))
-  }
-  it should "remove entries" in {
-    val cache = LRUCache[Int, Int](2)
-    cache.put(1, 1)
-    cache.put(2, 2)
-    assert(cache.get(1).contains(1))
-    assert(cache.get(2).contains(2))
-
-    assert(cache.remove(1).getOrElse(-1) == 1)
-    assert(cache.get(1).isEmpty)
-    assert(cache.get(2).contains(2))
-  }
-  it should "clear entries on close" in {
-    val cache = LRUCache[Int, Int](2)
-    cache.put(1, 1)
-    assert(cache.get(1).contains(1))
-    cache.close()
-    assert(cache.get(1).isEmpty)
-  }
-  it should "call onExpire in close" in {
-    val count = new AtomicInteger(0)
-    val cache =
-      LRUCache[Int, Int](
-        maxSize = 3,
-        onExpire = (_: Int, _: Int) => { count.getAndIncrement(); () }
-      )
-    cache.put(1, 1)
-    cache.put(2, 2)
-    cache.put(3, 3)
-    cache.put(4, 4)
-    assert(count.get == 1)
-    cache.close()
-    assert(count.get == 4)
-  }
-  it should "apply on remove function" in {
-    val value = new AtomicInteger(0)
-    val cache = LRUCache[Int, Int](1, (k: Int, v: Int) => value.set(k + v))
-    cache.put(1, 3)
-    cache.put(2, 2)
-    assert(value.get() == 4)
-    assert(cache.get(2).contains(2))
-  }
-  it should "print sorted entries in toString" in {
-    val cache = LRUCache[Int, Int](2)
-    cache.put(2, 2)
-    cache.put(1, 1)
-    assert(cache.toString == s"LRUCache(2 -> 2, 1 -> 1)")
-  }
-}