Merge pull request #4956 from eatkins/custom-show

Allow custom show for a scope

main-settings/src/main/scala/sbt/Def.scala

@@ -54,12 +54,14 @@ object Def extends Init[Scope] with TaskMacroExtra {
       keyNameColor: Option[String] = None,
   ): Show[ScopedKey[_]] =
     Show[ScopedKey[_]](
-      key =>
-        Scope.display(
-          key.scope,
-          withColor(key.key.label, keyNameColor),
-          ref => displayRelative2(current, ref)
-        )
+      key => {
+        val color: String => String = withColor(_, keyNameColor)
+        key.scope.extra.toOption
+          .flatMap(_.get(Scope.customShowString).map(color))
+          .getOrElse {
+            Scope.display(key.scope, color(key.key.label), ref => displayRelative2(current, ref))
+          }
+      }
     )
 
   private[sbt] def showShortKey(

main-settings/src/main/scala/sbt/Scope.scala

@@ -178,6 +178,22 @@ object Scope {
   ): String =
     displayMasked(scope, sep, showProject, mask, false)
 
+  /**
+   * Allows the user to override the result of `Scope.display` or `Scope.displayMasked` for a
+   * particular scope. This can be used to enhance super shell and/or error reporting for tasks
+   * that use mangled names. For example, one might have:
+   * {{{
+   *   val mangledKey = TaskKey[Unit]("foo_slash_bar")
+   *   val attributeMap = AttributeMap.empty.put(Scope.customShowString("foo/bar"))
+   *   val sanitizedKey = mangledKey.copy(scope = mangledKey.copy(extra = Select(attributeMap)))
+   *   sanitizedKey := { ... }
+   * }}}
+   *
+   * Now whenever the `foo_slash_bar` task specified by sanitizedKey is evaluated, it will display
+   * "foo/bar" in super shell progress and in the error message if an error is thrown.
+   */
+  val customShowString = AttributeKey[String]("scope-custom-show-string")
+
   /**
    * unified slash style introduced in sbt 1.1.0.
    * By default, sbt will no longer display the Zero-config,
@@ -193,20 +209,22 @@ object Scope {
       showZeroConfig: Boolean
   ): String = {
     import scope.{ project, config, task, extra }
-    val zeroConfig = if (showZeroConfig) "Zero /" else ""
-    val configPrefix = config.foldStrict(display, zeroConfig, "./")
-    val taskPrefix = task.foldStrict(_.label + " /", "", "./")
-    val extras = extra.foldStrict(_.entries.map(_.toString).toList, Nil, Nil)
-    val postfix = if (extras.isEmpty) "" else extras.mkString("(", ", ", ")")
-    if (scope == GlobalScope) "Global / " + sep + postfix
-    else
-      mask.concatShow(
-        appendSpace(projectPrefix(project, showProject)),
-        appendSpace(configPrefix),
-        appendSpace(taskPrefix),
-        sep,
-        postfix
-      )
+    extra.toOption.flatMap(_.get(customShowString)).getOrElse {
+      val zeroConfig = if (showZeroConfig) "Zero /" else ""
+      val configPrefix = config.foldStrict(display, zeroConfig, "./")
+      val taskPrefix = task.foldStrict(_.label + " /", "", "./")
+      val extras = extra.foldStrict(_.entries.map(_.toString).toList, Nil, Nil)
+      val postfix = if (extras.isEmpty) "" else extras.mkString("(", ", ", ")")
+      if (scope == GlobalScope) "Global / " + sep + postfix
+      else
+        mask.concatShow(
+          appendSpace(projectPrefix(project, showProject)),
+          appendSpace(configPrefix),
+          appendSpace(taskPrefix),
+          sep,
+          postfix
+        )
+    }
   }
 
   private[sbt] def appendSpace(s: String): String =

main-settings/src/test/scala/sbt/ScopeDisplaySpec.scala

@@ -0,0 +1,50 @@
+/*
+ * sbt
+ * Copyright 2011 - 2018, Lightbend, Inc.
+ * Copyright 2008 - 2010, Mark Harrah
+ * Licensed under Apache License 2.0 (see LICENSE)
+ */
+
+package sbt
+
+import org.scalatest.FlatSpec
+import sbt.internal.util.{ AttributeKey, AttributeMap }
+import sbt.io.syntax.file
+
+class ScopeDisplaySpec extends FlatSpec {
+  val project = ProjectRef(file("foo/bar"), "bar")
+  val mangledName = "bar_slash_blah_blah_blah"
+  val scopedKey = Def.ScopedKey(Scope.Global in project, AttributeKey[Task[String]](mangledName))
+  val am = AttributeMap.empty.put(Scope.customShowString, "blah")
+  val sanitizedKey = scopedKey.copy(scope = scopedKey.scope.copy(extra = Select(am)))
+  "Def.displayRelative2" should "display mangled name" in {
+    assert(Def.showRelativeKey2(project, None).show(scopedKey) == mangledName)
+  }
+  it should "display sanitized name with extra setting" in {
+    assert(Def.showRelativeKey2(project, None).show(sanitizedKey) == "blah")
+  }
+  "Scope.display" should "display the full scope" in {
+    val full = Scope.display(
+      scopedKey.scope,
+      "/",
+      (ref: Reference) =>
+        ref match {
+          case ProjectRef(_, n) => n
+          case _                => ???
+        }
+    )
+    assert(full == "bar /")
+  }
+  it should "display the sanitized scope" in {
+    val string = Scope.display(
+      sanitizedKey.scope,
+      "/",
+      (ref: Reference) =>
+        ref match {
+          case ProjectRef(_, n) => n
+          case _                => ???
+        }
+    )
+    assert(string == "blah")
+  }
+}