ExtModule's lacked support built in support for providing (#1154)

* ExtModule's lacked support built in support for providing
the verilog source. This changes creates traits that
can be used with ExtModule to provide the support currently found in
BlackBox

- Add support for ExtModule helpers
  - HasExtModuleResource to use addResource
  - HasExtModuleInline to use setInline
  - HasExtModulePath to use addPath
- Add tests of the above support.
  - Note: These tests use Stage instead of Driver
- Added ScalaDoc for HasBlackBoxInline#setInline

* Fix the danged trailing commas.

* Change to use `.transform` as the correct API for `ChiselStage`

1 files changed, 5 insertions, 0 deletions

diff --git a/src/main/scala/chisel3/util/BlackBoxUtils.scala b/src/main/scala/chisel3/util/BlackBoxUtils.scala
index 74d99ff8..21bd4dfa 100644
--- a/src/main/scala/chisel3/util/BlackBoxUtils.scala
+++ b/src/main/scala/chisel3/util/BlackBoxUtils.scala
@@ -32,6 +32,11 @@ trait HasBlackBoxResource extends BlackBox {
 trait HasBlackBoxInline extends BlackBox {
   self: BlackBox =>
 
+  /** Creates a black box verilog file, from the contents of a local string
+    *
+    * @param blackBoxName   The black box module name, to create filename
+    * @param blackBoxInline The black box contents
+    */
   def setInline(blackBoxName: String, blackBoxInline: String): Unit = {
     val anno = new ChiselAnnotation with RunFirrtlTransform {
       def toFirrtl = BlackBoxInlineAnno(self.toNamed, blackBoxName, blackBoxInline)