Escape special characters in Property String literals (backport #4564) (#4565)

* Escape special characters in Property String literals (#4564)

(cherry picked from commit dc39308)

* Tweak change to make it binary compatible

---------

Co-authored-by: Jack Koenig <[email protected]>

Author: mergify[bot]

core/src/main/scala/chisel3/properties/Property.scala

@@ -147,7 +147,7 @@ private[chisel3] object PropertyType extends LowPriorityPropertyTypeInstances {
     }
 
   implicit val stringPropertyTypeInstance: SimplePropertyType[String] =
-    makeSimple[String](fir.StringPropertyType, fir.StringPropertyLiteral(_))
+    makeSimple[String](fir.StringPropertyType, s => fir.StringPropertyLiteral(s))
 
   implicit val boolPropertyTypeInstance: SimplePropertyType[Boolean] =
     makeSimple[Boolean](fir.BooleanPropertyType, fir.BooleanPropertyLiteral(_))

firrtl/src/main/scala/firrtl/ir/Serializer.scala

@@ -113,7 +113,7 @@ object Serializer {
     case DoublePropertyLiteral(value) =>
       b ++= "Double("; b ++= value.toString(); b ++= ")"
     case StringPropertyLiteral(value) =>
-      b ++= "String(\""; b ++= value; b ++= "\")"
+      b ++= "String("; b ++= StringLit(value).escape; b ++= ")"
     case BooleanPropertyLiteral(value) =>
       b ++= s"Bool(${value})"
     case PathPropertyLiteral(value) =>

src/test/scala/chiselTests/properties/PropertySpec.scala

@@ -132,6 +132,31 @@ class PropertySpec extends ChiselFlatSpec with MatchesAndOmits {
     )()
   }
 
+  it should "escape special characters in Property String literals" in {
+    val input = "foo\"\n\t\\bar"
+    val expected = """foo\"\n\t\\bar"""
+    val chirrtl = ChiselStage.emitCHIRRTL(new RawModule {
+      val propOut = IO(Output(Property[String]()))
+      propOut := Property(input)
+    })
+
+    matchesAndOmits(chirrtl)(
+      s"""propassign propOut, String("$expected")"""
+    )()
+  }
+
+  it should "not escape characters that do not need escaping in Property String literals" in {
+    val input = "foo!@#$%^&*()_+bar"
+    val chirrtl = ChiselStage.emitCHIRRTL(new RawModule {
+      val propOut = IO(Output(Property[String]()))
+      propOut := Property(input)
+    })
+
+    matchesAndOmits(chirrtl)(
+      s"""propassign propOut, String("$input")"""
+    )()
+  }
+
   it should "support Boolean as a Property type" in {
     val chirrtl = ChiselStage.emitCHIRRTL(new RawModule {
       val boolProp = IO(Input(Property[Boolean]()))