ir: store FileInfo string in escaped format (#1690)

This should speed up the common case
as the compiler never operates on the
unescaped string.
The new escape function also fixes a bug
where ']' was not escaped even though it
is the delimiting character for FileInfo.
In order to maintain backwards
compatibility for the ProtoBuf format,
this patch adds escape/unescape calls
when going from/to protobuf format.
For better performance we should consider
changing the protobuf format.

1 files changed, 23 insertions, 0 deletions

diff --git a/src/test/scala/firrtlTests/InfoSpec.scala b/src/test/scala/firrtlTests/InfoSpec.scala
index 48567d69..01e0a0ac 100644
--- a/src/test/scala/firrtlTests/InfoSpec.scala
+++ b/src/test/scala/firrtlTests/InfoSpec.scala
@@ -172,4 +172,27 @@ class InfoSpec extends FirrtlFlatSpec with FirrtlMatchers {
     val expectedInfos = Seq(FileInfo(StringLit("Top.scala 15:14")), FileInfo(StringLit("myfile.fir 6:4")))
     circuitState should containTree { case MultiInfo(`expectedInfos`) => true }
   }
+
+  "FileInfo" should "be able to contain a escaped characters" in {
+    def input(info: String): String =
+      s"""circuit m: @[$info]
+        |  module m:
+        |    skip
+        |""".stripMargin
+    def parseInfo(info: String): FileInfo = {
+      firrtl.Parser.parse(input(info)).info.asInstanceOf[FileInfo]
+    }
+
+    parseInfo("test\\ntest").escaped should be ("test\\ntest")
+    parseInfo("test\\ntest").unescaped should be ("test\ntest")
+    parseInfo("test\\ttest").escaped should be ("test\\ttest")
+    parseInfo("test\\ttest").unescaped should be ("test\ttest")
+    parseInfo("test\\\\test").escaped should be ("test\\\\test")
+    parseInfo("test\\\\test").unescaped should be ("test\\test")
+    parseInfo("test\\]test").escaped should be ("test\\]test")
+    parseInfo("test\\]test").unescaped should be ("test]test")
+    parseInfo("test[\\][\\]test").escaped should be ("test[\\][\\]test")
+    parseInfo("test[\\][\\]test").unescaped should be ("test[][]test")
+  }
+
 }