From b51818bc4e254a731afed8e3ddcb4a82790ff33a Mon Sep 17 00:00:00 2001
From: Christian Rinderknecht <Christian.Rinderknecht@tezcore.com>
Date: Fri, 21 Feb 2020 12:30:32 +0100
Subject: [PATCH] Fixed parsing and source pretty-printing of recursive
 functions.

---
 src/passes/1-parser/pascaligo/LexToken.mll |  1 +
 src/passes/1-parser/pascaligo/Parser.mly   | 44 +++-------------------
 src/passes/1-parser/pascaligo/ParserLog.ml | 22 +++++++----
 3 files changed, 20 insertions(+), 47 deletions(-)

diff --git a/src/passes/1-parser/pascaligo/LexToken.mll b/src/passes/1-parser/pascaligo/LexToken.mll
index 4b6ab211c..5711bbac6 100644
--- a/src/passes/1-parser/pascaligo/LexToken.mll
+++ b/src/passes/1-parser/pascaligo/LexToken.mll
@@ -364,6 +364,7 @@ let keywords = [
   (fun reg -> Or         reg);
   (fun reg -> Patch      reg);
   (fun reg -> Record     reg);
+  (fun reg -> Recursive  reg);
   (fun reg -> Remove     reg);
   (fun reg -> Set        reg);
   (fun reg -> Skip       reg);
diff --git a/src/passes/1-parser/pascaligo/Parser.mly b/src/passes/1-parser/pascaligo/Parser.mly
index 9dbaeafe8..20b89b278 100644
--- a/src/passes/1-parser/pascaligo/Parser.mly
+++ b/src/passes/1-parser/pascaligo/Parser.mly
@@ -263,47 +263,13 @@ fun_expr:
 (* Function declarations *)
 
 open_fun_decl:
-  "function" fun_name parameters ":" type_expr "is"
-  block "with" expr {
-    Scoping.check_reserved_name $2;
-    let stop   = expr_to_region $9 in
-    let region = cover $1 stop
-    and value  = {kwd_recursive= None;
-                  kwd_function = $1;  
-                  fun_name     = $2;
-                  param        = $3;
-                  colon        = $4;
-                  ret_type     = $5;
-                  kwd_is       = $6;
-                  block_with   = Some ($7, $8);
-                  return       = $9;
-                  terminator   = None;
-                  attributes   = None}
-    in {region; value}
-  }
-| "function" fun_name parameters ":" type_expr "is" expr {
-    Scoping.check_reserved_name $2;
-    let stop   = expr_to_region $7 in
-    let region = cover $1 stop
-    and value  = {kwd_recursive= None;
-                  kwd_function = $1;
-                  fun_name     = $2;
-                  param        = $3;
-                  colon        = $4;
-                  ret_type     = $5;
-                  kwd_is       = $6;
-                  block_with   = None;
-                  return       = $7;
-                  terminator   = None;
-                  attributes   = None}
-    in {region; value} }
-| "recursive" "function" fun_name parameters ":" type_expr "is"
+  "recursive"? "function" fun_name parameters ":" type_expr "is"
   block "with" expr {
     Scoping.check_reserved_name $3;
     let stop   = expr_to_region $10 in
     let region = cover $2 stop
-    and value  = {kwd_recursive= Some($1);
-                  kwd_function = $2;  
+    and value  = {kwd_recursive= $1;
+                  kwd_function = $2;
                   fun_name     = $3;
                   param        = $4;
                   colon        = $5;
@@ -315,11 +281,11 @@ open_fun_decl:
                   attributes   = None}
     in {region; value}
   }
-| "recursive" "function" fun_name parameters ":" type_expr "is" expr {
+| "recursive"? "function" fun_name parameters ":" type_expr "is" expr {
     Scoping.check_reserved_name $3;
     let stop   = expr_to_region $8 in
     let region = cover $2 stop
-    and value  = {kwd_recursive= Some($1);
+    and value  = {kwd_recursive= $1;
                   kwd_function = $2;
                   fun_name     = $3;
                   param        = $4;
diff --git a/src/passes/1-parser/pascaligo/ParserLog.ml b/src/passes/1-parser/pascaligo/ParserLog.ml
index 93c5f7352..ccca02968 100644
--- a/src/passes/1-parser/pascaligo/ParserLog.ml
+++ b/src/passes/1-parser/pascaligo/ParserLog.ml
@@ -609,8 +609,8 @@ and print_field_path_assign state {value; _} =
   print_nsepseq state "field_path" print_var field_path;
   print_token state equal "=";
   print_expr  state field_expr
-  
-and print_update_expr state {value; _} = 
+
+and print_update_expr state {value; _} =
   let {record; kwd_with; updates} = value in
   print_path state record;
   print_token state kwd_with "with";
@@ -859,20 +859,26 @@ and pp_declaration state = function
 and pp_attr_decl state = pp_ne_injection pp_string state
 
 and pp_fun_decl state decl =
-  let arity = 5 in
+  let arity, start =
+    match decl.kwd_recursive with
+      None -> 5,0
+    | Some _ ->
+       let state = state#pad 6 0 in
+       let () = pp_node state "recursive"
+       in 6,1 in
   let () =
-    let state = state#pad arity 0 in
+    let state = state#pad arity start in
     pp_ident state decl.fun_name in
   let () =
-    let state = state#pad arity 1 in
+    let state = state#pad arity (start + 1) in
     pp_node state "<parameters>";
     pp_parameters state decl.param in
   let () =
-    let state = state#pad arity 2 in
+    let state = state#pad arity (start + 2) in
     pp_node state "<return type>";
     pp_type_expr (state#pad 1 0) decl.ret_type in
   let () =
-    let state = state#pad arity 3 in
+    let state = state#pad arity (start + 3) in
     pp_node state "<body>";
     let statements =
       match decl.block_with with
@@ -880,7 +886,7 @@ and pp_fun_decl state decl =
       | None -> Instr (Skip Region.ghost), [] in
     pp_statements state statements in
   let () =
-    let state = state#pad arity 4 in
+    let state = state#pad arity (start + 4) in
     pp_node state "<return>";
     pp_expr (state#pad 1 0) decl.return
   in ()