Fix serialization of whens with empty blocks (#2560)

Also get rid of whitespace-only lines that were emitted after every when
block.

1 files changed, 5 insertions, 0 deletions

diff --git a/src/test/scala/firrtlTests/SerializerSpec.scala b/src/test/scala/firrtlTests/SerializerSpec.scala
index 797a6045..9a984d60 100644
--- a/src/test/scala/firrtlTests/SerializerSpec.scala
+++ b/src/test/scala/firrtlTests/SerializerSpec.scala
@@ -116,4 +116,9 @@ class SerializerSpec extends AnyFlatSpec with Matchers {
     serialized should be(childModuleTabbed)
   }
 
+  it should "emit whens with empty Blocks correctly" in {
+    val when = Conditionally(NoInfo, Reference("cond"), Block(Seq()), EmptyStmt)
+    val serialized = Serializer.serialize(when, 1)
+    serialized should be("  when cond :\n    skip\n")
+  }
 }