Use ChiselStage in Tests

This migrates the tests to Chisel 3.4/FIRRTL 1.4. This primarily
involves removing usages of deprecated methods including:

- Remove usages of Driver
- Use ChiselStage methods instead of BackendCompilationUtilities
  methods
- Use Dependency API for custom transforms
- Use extractCause to unpack StackError

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

2 files changed, 20 insertions, 13 deletions

diff --git a/src/test/scala/chiselTests/util/random/LFSRSpec.scala b/src/test/scala/chiselTests/util/random/LFSRSpec.scala
index 9afe7670..1dc2db41 100644
--- a/src/test/scala/chiselTests/util/random/LFSRSpec.scala
+++ b/src/test/scala/chiselTests/util/random/LFSRSpec.scala
@@ -3,6 +3,7 @@
 package chiselTests.util.random
 
 import chisel3._
+import chisel3.stage.ChiselStage
 import chisel3.util.{Cat, Counter, Enum}
 import chisel3.util.random._
 import chisel3.testers.BasicTester
@@ -105,7 +106,7 @@ class LFSRResetTester(gen: => LFSR, lockUpValue: BigInt) extends BasicTester {
 
 }
 
-class LFSRSpec extends ChiselFlatSpec {
+class LFSRSpec extends ChiselFlatSpec with Utils {
 
   def periodCheck(gen: (Int, Set[Int], LFSRReduce) => PRNG, reduction: LFSRReduce, range: Range): Unit = {
     it should s"have a maximal period over a range of widths (${range.head} to ${range.last}) using ${reduction.getClass}" in {
@@ -122,13 +123,15 @@ class LFSRSpec extends ChiselFlatSpec {
   behavior of "LFSR"
 
   it should "throw an exception if initialized to a seed of zero for XOR configuration" in {
-    { the [IllegalArgumentException] thrownBy elaborate(new FooLFSR(XOR, Some(0))) }
-      .getMessage should include ("Seed cannot be zero")
+    { the [IllegalArgumentException] thrownBy extractCause[IllegalArgumentException] {
+       ChiselStage.elaborate(new FooLFSR(XOR, Some(0))) }
+    }.getMessage should include ("Seed cannot be zero")
   }
 
   it should "throw an exception if initialized to a seed of all ones for XNOR configuration" in {
-    { the [IllegalArgumentException] thrownBy elaborate(new FooLFSR(XNOR, Some(15))) }
-      .getMessage should include ("Seed cannot be all ones")
+    { the [IllegalArgumentException] thrownBy extractCause[IllegalArgumentException] {
+       ChiselStage.elaborate(new FooLFSR(XNOR, Some(15))) }
+    }.getMessage should include ("Seed cannot be all ones")
   }
 
   it should "reset correctly without a seed for XOR configuration" in {
@@ -142,8 +145,9 @@ class LFSRSpec extends ChiselFlatSpec {
   behavior of "MaximalPeriodGaloisLFSR"
 
   it should "throw an exception if no LFSR taps are known" in {
-    { the [IllegalArgumentException] thrownBy elaborate(new MaxPeriodGaloisLFSR(787)) }
-      .getMessage should include ("No max period LFSR taps stored for requested width")
+    { the [IllegalArgumentException] thrownBy extractCause[IllegalArgumentException] {
+       ChiselStage.elaborate(new MaxPeriodGaloisLFSR(787)) }
+    }.getMessage should include ("No max period LFSR taps stored for requested width")
   }
 
   periodCheck((w: Int, t: Set[Int], r: LFSRReduce) => new GaloisLFSR(w, t, reduction=r), XOR, 2 to 16)
diff --git a/src/test/scala/chiselTests/util/random/PRNGSpec.scala b/src/test/scala/chiselTests/util/random/PRNGSpec.scala
index 341fb685..bf10a1c0 100644
--- a/src/test/scala/chiselTests/util/random/PRNGSpec.scala
+++ b/src/test/scala/chiselTests/util/random/PRNGSpec.scala
@@ -3,11 +3,12 @@
 package chiselTests.util.random
 
 import chisel3._
+import chisel3.stage.ChiselStage
 import chisel3.testers.BasicTester
 import chisel3.util.Counter
 import chisel3.util.random.PRNG
 
-import chiselTests.ChiselFlatSpec
+import chiselTests.{ChiselFlatSpec, Utils}
 
 class CyclePRNG(width: Int, seed: Option[BigInt], step: Int, updateSeed: Boolean)
     extends PRNG(width, seed, step, updateSeed) {
@@ -61,18 +62,20 @@ class PRNGUpdateSeedTest(updateSeed: Boolean, seed: BigInt, expected: BigInt) ex
 
 }
 
-class PRNGSpec extends ChiselFlatSpec {
+class PRNGSpec extends ChiselFlatSpec with Utils {
 
   behavior of "PRNG"
 
   it should "throw an exception if the step size is < 1" in {
-    { the [IllegalArgumentException] thrownBy elaborate(new CyclePRNG(0, Some(1), 1, true)) }
-      .getMessage should include ("Width must be greater than zero!")
+    { the [IllegalArgumentException] thrownBy extractCause[IllegalArgumentException] {
+       ChiselStage.elaborate(new CyclePRNG(0, Some(1), 1, true)) }
+    }.getMessage should include ("Width must be greater than zero!")
   }
 
   it should "throw an exception if the step size is <= 0" in {
-    { the [IllegalArgumentException] thrownBy elaborate(new CyclePRNG(1, Some(1), 0, true)) }
-      .getMessage should include ("Step size must be greater than one!")
+    { the [IllegalArgumentException] thrownBy extractCause[IllegalArgumentException] {
+       ChiselStage.elaborate(new CyclePRNG(1, Some(1), 0, true)) }
+    }.getMessage should include ("Step size must be greater than one!")
   }
 
   it should "handle non-unary steps" in {