Add ShellOption, DeletedWrapper

Abstracts away option writing such that users no longer have to
understand scopt semantics. This adds a ShellOption class and a
HasShellOptions trait for something which provides one or more
ShellOptions. This refactors the FIRRTL codebase to use this style of
option specification.

Adds and uses DeletedWrapper to automatically generate
DeletedAnnotations.

Signed-off-by: Schuyler Eldridge <schuyler.eldridge@ibm.com>

1 files changed, 43 insertions, 0 deletions

diff --git a/src/main/scala/firrtl/options/phases/DeletedWrapper.scala b/src/main/scala/firrtl/options/phases/DeletedWrapper.scala
new file mode 100644
index 00000000..0a959f32
--- /dev/null
+++ b/src/main/scala/firrtl/options/phases/DeletedWrapper.scala
@@ -0,0 +1,43 @@
+// See LICENSE for license details.
+
+package firrtl.options.phases
+
+import firrtl.AnnotationSeq
+import firrtl.annotations.DeletedAnnotation
+import firrtl.options.{Phase, Translator}
+
+import scala.collection.mutable
+
+/** Wrap a [[firrtl.options.Phase Phase]] such that any [[firrtl.annotations.Annotation Annotation]] removed by the
+  * wrapped [[firrtl.options.Phase Phase]] will be added as [[firrtl.annotations.DeletedAnnotation DeletedAnnotation]]s.
+  * @param p a [[firrtl.options.Phase Phase]] to wrap
+  */
+class DeletedWrapper(p: Phase) extends Phase with Translator[AnnotationSeq, (AnnotationSeq, AnnotationSeq)] {
+
+  override lazy val name: String = p.name
+
+  def aToB(a: AnnotationSeq): (AnnotationSeq, AnnotationSeq) = (a, a)
+
+  def bToA(b: (AnnotationSeq, AnnotationSeq)): AnnotationSeq = {
+
+    val (in, out) = (mutable.LinkedHashSet() ++ b._1, mutable.LinkedHashSet() ++ b._2)
+
+    (in -- out).map {
+      case DeletedAnnotation(n, a) => DeletedAnnotation(s"$n+$name", a)
+      case a                       => DeletedAnnotation(name, a)
+    }.toSeq ++ b._2
+
+  }
+
+  def internalTransform(b: (AnnotationSeq, AnnotationSeq)): (AnnotationSeq, AnnotationSeq) = (b._1, p.transform(b._2))
+
+}
+
+object DeletedWrapper {
+
+  /** Wrap a [[firrtl.options.Phase Phase]] in a [[DeletedWrapper]]
+    * @param p a [[firrtl.options.Phase Phase]] to wrap
+    */
+  def apply(p: Phase): DeletedWrapper = new DeletedWrapper(p)
+
+}