From ebb7e66a2648467520edc30ed453d87ac7e2d9be Mon Sep 17 00:00:00 2001
From: Olivier Deckers <deckers.olivier@gmail.com>
Date: Fri, 3 Nov 2017 15:21:39 +0100
Subject: [PATCH] Implemented clean task + added integration test. Fixes #685

---
 .../src/main/scala/coursier/CoursierPlugin.scala    |  7 ++++++-
 sbt-coursier/src/main/scala/coursier/Tasks.scala    |  8 ++++----
 .../src/sbt-test/sbt-coursier/clean/build.sbt       | 13 +++++++++++++
 .../sbt-coursier/clean/project/helper.scala         |  9 +++++++++
 .../sbt-test/sbt-coursier/clean/project/plugins.sbt | 11 +++++++++++
 sbt-coursier/src/sbt-test/sbt-coursier/clean/test   |  5 +++++
 6 files changed, 48 insertions(+), 5 deletions(-)
 create mode 100644 sbt-coursier/src/sbt-test/sbt-coursier/clean/build.sbt
 create mode 100644 sbt-coursier/src/sbt-test/sbt-coursier/clean/project/helper.scala
 create mode 100644 sbt-coursier/src/sbt-test/sbt-coursier/clean/project/plugins.sbt
 create mode 100644 sbt-coursier/src/sbt-test/sbt-coursier/clean/test

diff --git a/sbt-coursier/src/main/scala/coursier/CoursierPlugin.scala b/sbt-coursier/src/main/scala/coursier/CoursierPlugin.scala
index 29bcb36ea..e8f209766 100644
--- a/sbt-coursier/src/main/scala/coursier/CoursierPlugin.scala
+++ b/sbt-coursier/src/main/scala/coursier/CoursierPlugin.scala
@@ -9,7 +9,7 @@ object CoursierPlugin extends AutoPlugin {
 
   override def trigger = allRequirements
 
-  override def requires = sbt.plugins.IvyPlugin
+  override def requires = sbt.plugins.JvmPlugin
 
   object autoImport {
     val coursierParallelDownloads = Keys.coursierParallelDownloads
@@ -153,6 +153,11 @@ object CoursierPlugin extends AutoPlugin {
     shadedConfigOpt: Option[(String, String)],
     packageConfigs: Seq[(Configuration, String)]
   ) = hackHack ++ Seq(
+    clean := {
+      clean.value
+      Tasks.resolutionsCache.clear()
+      Tasks.reportsCache.clear()
+    },
     coursierResolvers := Tasks.coursierResolversTask.value,
     coursierRecursiveResolvers := Tasks.coursierRecursiveResolversTask.value,
     coursierSbtResolvers := {
diff --git a/sbt-coursier/src/main/scala/coursier/Tasks.scala b/sbt-coursier/src/main/scala/coursier/Tasks.scala
index ba213d7c5..c46ae9dd9 100644
--- a/sbt-coursier/src/main/scala/coursier/Tasks.scala
+++ b/sbt-coursier/src/main/scala/coursier/Tasks.scala
@@ -398,7 +398,7 @@ object Tasks {
     }
   }
 
-  private final case class ResolutionCacheKey(
+  private[coursier] final case class ResolutionCacheKey(
     project: Project,
     repositories: Seq[Repository],
     userEnabledProfiles: Set[String],
@@ -406,7 +406,7 @@ object Tasks {
     sbtClassifiers: Boolean
   )
 
-  private final case class ReportCacheKey(
+  private[coursier] final case class ReportCacheKey(
     project: Project,
     resolution: Map[Set[String], Resolution],
     withClassifiers: Boolean,
@@ -414,10 +414,10 @@ object Tasks {
     ignoreArtifactErrors: Boolean
   )
 
-  private val resolutionsCache = new mutable.HashMap[ResolutionCacheKey, Map[Set[String], Resolution]]
+  private[coursier] val resolutionsCache = new mutable.HashMap[ResolutionCacheKey, Map[Set[String], Resolution]]
   // these may actually not need to be cached any more, now that the resolutions
   // are cached
-  private val reportsCache = new mutable.HashMap[ReportCacheKey, UpdateReport]
+  private[coursier] val reportsCache = new mutable.HashMap[ReportCacheKey, UpdateReport]
 
   private def forcedScalaModules(
     scalaOrganization: String,
diff --git a/sbt-coursier/src/sbt-test/sbt-coursier/clean/build.sbt b/sbt-coursier/src/sbt-test/sbt-coursier/clean/build.sbt
new file mode 100644
index 000000000..f0b2ed640
--- /dev/null
+++ b/sbt-coursier/src/sbt-test/sbt-coursier/clean/build.sbt
@@ -0,0 +1,13 @@
+scalaVersion := "2.11.8"
+
+val checkEmpty = TaskKey[Unit]("checkEmpty")
+
+checkEmpty := {
+  assert(coursier.Helper.checkEmpty)
+}
+
+val checkNotEmpty = TaskKey[Unit]("checkNotEmpty")
+
+checkNotEmpty := {
+  assert(!coursier.Helper.checkEmpty)
+}
\ No newline at end of file
diff --git a/sbt-coursier/src/sbt-test/sbt-coursier/clean/project/helper.scala b/sbt-coursier/src/sbt-test/sbt-coursier/clean/project/helper.scala
new file mode 100644
index 000000000..000111d37
--- /dev/null
+++ b/sbt-coursier/src/sbt-test/sbt-coursier/clean/project/helper.scala
@@ -0,0 +1,9 @@
+package coursier
+
+object Helper {
+
+  def checkEmpty(): Boolean = {
+    Tasks.resolutionsCache.isEmpty && Tasks.reportsCache.isEmpty
+  }
+
+}
\ No newline at end of file
diff --git a/sbt-coursier/src/sbt-test/sbt-coursier/clean/project/plugins.sbt b/sbt-coursier/src/sbt-test/sbt-coursier/clean/project/plugins.sbt
new file mode 100644
index 000000000..152225a9e
--- /dev/null
+++ b/sbt-coursier/src/sbt-test/sbt-coursier/clean/project/plugins.sbt
@@ -0,0 +1,11 @@
+{
+  val pluginVersion = sys.props.getOrElse(
+    "plugin.version",
+    throw new RuntimeException(
+      """|The system property 'plugin.version' is not defined.
+         |Specify this property using the scriptedLaunchOpts -D.""".stripMargin
+    )
+  )
+
+  addSbtPlugin("io.get-coursier" % "sbt-coursier" % pluginVersion)
+}
diff --git a/sbt-coursier/src/sbt-test/sbt-coursier/clean/test b/sbt-coursier/src/sbt-test/sbt-coursier/clean/test
new file mode 100644
index 000000000..6dc6f6976
--- /dev/null
+++ b/sbt-coursier/src/sbt-test/sbt-coursier/clean/test
@@ -0,0 +1,5 @@
+> checkEmpty
+> update
+> checkNotEmpty
+> clean
+> checkEmpty