1 files changed, 52 insertions, 0 deletions
diff --git a/src/test/scala/firrtlTests/execution/ParserHelpers.scala b/src/test/scala/firrtlTests/execution/ParserHelpers.scala
new file mode 100644
index 00000000..3472c19c
--- /dev/null
+++ b/src/test/scala/firrtlTests/execution/ParserHelpers.scala
@@ -0,0 +1,52 @@
+package firrtlTests.execution
+
+import firrtl._
+import firrtl.ir._
+
+class ParserHelperException(val pe: ParserException, input: String)
+    extends FirrtlUserException(s"Got error ${pe.toString} while parsing input:\n${input}")
+
+/**
+  * A utility class that parses a FIRRTL string representing a statement to a sub-AST
+  */
+object ParseStatement {
+  private def wrapStmtStr(stmtStr: String): String = {
+    val indent = "    "
+    val indented = stmtStr.split("\n").mkString(indent, s"\n${indent}", "")
+    s"""circuit ${DUTRules.dutName} :
+         |  module ${DUTRules.dutName} :
+         |    input clock : Clock
+         |    input reset : UInt<1>
+         |${indented}""".stripMargin
+  }
+
+  private def parse(stmtStr: String): Circuit = {
+    try {
+      Parser.parseString(wrapStmtStr(stmtStr), Parser.IgnoreInfo)
+    } catch {
+      case e: ParserException => throw new ParserHelperException(e, stmtStr)
+    }
+  }
+
+  def apply(stmtStr: String): Statement = {
+    val c = parse(stmtStr)
+    val stmt = c.modules.collectFirst { case Module(_, _, _, b: Block) => b.stmts.head }
+    stmt.get
+  }
+
+  private[execution] def makeDUT(body: String): Circuit = parse(body)
+}
+
+/**
+  * A utility class that parses a FIRRTL string representing an expression to a sub-AST
+  */
+object ParseExpression {
+  def apply(expStr: String): Expression = {
+    try {
+      val s = ParseStatement(s"${expStr} is invalid")
+      s.asInstanceOf[IsInvalid].expr
+    } catch {
+      case e: ParserHelperException => throw new ParserHelperException(e.pe, expStr)
+    }
+  }
+}