Make BaseModule.name lazy

This changes BaseModule.name to be lazy (instead of eager) to enable a
desiredName to be a function of a sub-instance. This includes a test case
showing the new behavior.

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

2 files changed, 10 insertions, 1 deletions

diff --git a/chiselFrontend/src/main/scala/chisel3/core/Module.scala b/chiselFrontend/src/main/scala/chisel3/core/Module.scala
index 88013bae..89dd2dee 100644
--- a/chiselFrontend/src/main/scala/chisel3/core/Module.scala
+++ b/chiselFrontend/src/main/scala/chisel3/core/Module.scala
@@ -180,7 +180,7 @@ abstract class BaseModule extends HasId {
   def desiredName = this.getClass.getName.split('.').last
 
   /** Legalized name of this module. */
-  final val name = Builder.globalNamespace.name(desiredName)
+  final lazy val name = Builder.globalNamespace.name(desiredName)
 
   /** Returns a FIRRTL ModuleName that references this object
     * @note Should not be called until circuit elaboration is complete
diff --git a/src/test/scala/chiselTests/Module.scala b/src/test/scala/chiselTests/Module.scala
index 968e7578..dc44838a 100644
--- a/src/test/scala/chiselTests/Module.scala
+++ b/src/test/scala/chiselTests/Module.scala
@@ -62,6 +62,12 @@ class ModuleRewrap extends Module {
   val inst2 = Module(inst)
 }
 
+class ModuleWrapper(gen: => Module) extends Module {
+  val io = IO(new Bundle{})
+  val child = Module(gen)
+  override lazy val desiredName = s"${child.desiredName}Wrapper"
+}
+
 class ModuleSpec extends ChiselPropSpec {
 
   property("ModuleVec should elaborate") {
@@ -138,4 +144,7 @@ class ModuleSpec extends ChiselPropSpec {
           "a" -> m.a, "b" -> m.b))
     })
   }
+  property("A desiredName parameterized by a submodule should work") {
+    Driver.elaborate(() => new ModuleWrapper(new ModuleWire)).name should be ("ModuleWireWrapper")
+  }
 }