Multireturn bugfix (#238)

aqua-src/ret.aqua

@@ -1,15 +1,20 @@
-service Getter("test"):
+service GetStr("multiret-test"):
-    createStr: u32 -> string
+    retStr: string -> string
 
-service OpO("op"):
+service GetNum("multiret-num"):
-    identity: string -> string
+    retNum: -> u8
 
--- a question mark means that this constant could be rewritten before this definition
+const someNum = 5
-const anotherConst ?= "default-str"
+const someStr = "some-str"
-const uniqueConst ?= 5
 
-func callConstant() -> []string, u8:
+func tupleFunc() -> string, u8:
+    str <- GetStr.retStr(someStr)
+    n <- GetNum.retNum()
+    <- str, n
+
+func multiReturnFunc(somethingToReturn: []u8, smthOption: ?string) -> []string, u8, string, []u8, ?string, u8:
     res: *string
-    res <- Getter.createStr(uniqueConst)
+    res <- GetStr.retStr(someStr)
-    res <- OpO.identity(anotherConst)
+    res <- GetStr.retStr("random-str")
-    <- res, 5
+    res, tNum <- tupleFunc()
+    <- res, 5, someStr, somethingToReturn, smthOption, tNum

model/src/main/scala/aqua/model/func/FuncCallable.scala

@@ -167,7 +167,7 @@ case class FuncCallable(
             case ((ops, rets), (_, r)) => (ops, r :: rets)
           }
 
-        FuncOps.seq(ops.reverse: _*) -> rets
+        FuncOps.seq(ops.reverse: _*) -> rets.reverse
       }
   }
 

model/src/main/scala/aqua/model/transform/ResolveFunc.scala

@@ -44,6 +44,13 @@ case class ResolveFunc(
       case t => t
     }).toLabelledList(returnVar)
 
+    val retModel = returnType.map { case (l, t) => VarModel(l, t) }
+
+    val funcCall = Call(
+      func.arrowType.domain.toLabelledList().map(ad => VarModel(ad._1, ad._2)),
+      returnType.map { case (l, t) => Call.Export(l, t) }
+    )
+
     FuncCallable(
       wrapCallableName,
       transform(
@@ -51,13 +58,10 @@ case class ResolveFunc(
           FuncOps
             .callArrow(
               func.funcName,
-              Call(
+              funcCall
-                func.arrowType.domain.toLabelledList().map(ad => VarModel(ad._1, ad._2)),
+            ) :: (returnType.headOption
-                returnType.map { case (l, t) => Call.Export(l, t) }
+            .map(_ => returnCallback(retModel))
-              )
+            .toList): _*
-            ) :: returnType.headOption
-            .map(_ => returnCallback(returnType.map { case (l, t) => VarModel(l, t) }))
-            .toList: _*
         )
       ),
       ArrowType(ConsType.cons(func.funcName, func.arrowType, NilType), NilType),

semantics/src/main/scala/aqua/semantics/expr/FuncSem.scala

@@ -96,6 +96,7 @@ class FuncSem[F[_]](val expr: FuncExpr[F]) extends AnyVal {
             .map(vs.prependedAll)
         )
       })
+      .map(_.reverse)
       .flatMap(retModel =>
         // Erase arguments and internal variables
         A.endScope() >> N.endScope() >> (bodyGen match {

types/src/main/scala/aqua/types/Type.scala

@@ -94,7 +94,7 @@ object ConsType {
 }
 
 case class LabelledConsType(label: String, `type`: Type, tail: ProductType) extends ConsType {
-  override def toString: String = s"($label: " + `type` + s" :: $tail"
+  override def toString: String = s"($label: " + `type` + s") :: $tail"
 }
 
 case class UnlabelledConsType(`type`: Type, tail: ProductType) extends ConsType {