experiment: modify candid tooling to preserve source occurrences of blob types when parsing and pretty-printing candid sources

rust/candid/src/pretty/candid.rs

@@ -187,13 +187,18 @@ fn pp_service(serv: &[(String, Type)]) -> RcDoc {
 }
 
 fn pp_defs(env: &TypeEnv) -> RcDoc {
-    lines(env.0.iter().map(|(id, ty)| {
-        kwd("type")
-            .append(ident(id))
-            .append(kwd("="))
-            .append(pp_ty(ty))
-            .append(";")
-    }))
+    lines(
+        env.0
+            .iter()
+            .filter(|(id, _)| *id != "blob")
+            .map(|(id, ty)| {
+                kwd("type")
+                    .append(ident(id))
+                    .append(kwd("="))
+                    .append(pp_ty(ty))
+                    .append(";")
+            }),
+    )
 }
 
 fn pp_actor(ty: &Type) -> RcDoc {

rust/candid/src/types/type_env.rs

@@ -7,7 +7,9 @@ pub struct TypeEnv(pub BTreeMap<String, Type>);
 
 impl TypeEnv {
     pub fn new() -> Self {
-        TypeEnv(BTreeMap::new())
+        let mut map = BTreeMap::new();
+        map.insert("blob".into(), TypeInner::Vec(TypeInner::Nat8.into()).into());
+        TypeEnv(map)
     }
     pub fn merge<'a>(&'a mut self, env: &TypeEnv) -> Result<&'a mut Self> {
         for (k, v) in &env.0 {

rust/candid_parser/src/bindings/javascript.rs

@@ -116,7 +116,13 @@ fn pp_ty(ty: &Type) -> RcDoc {
         Text => str("IDL.Text"),
         Reserved => str("IDL.Reserved"),
         Empty => str("IDL.Empty"),
-        Var(ref s) => ident(s),
+        Var(ref s) => {
+            if s == "blob" {
+                str("IDL.Vec").append(enclose("(", str("IDL.Nat8"), ")"))
+            } else {
+                ident(s)
+            }
+        }
         Principal => str("IDL.Principal"),
         Opt(ref t) => str("IDL.Opt").append(enclose("(", pp_ty(t), ")")),
         Vec(ref t) => str("IDL.Vec").append(enclose("(", pp_ty(t), ")")),
@@ -199,7 +205,7 @@ fn pp_defs<'a>(
         recs.iter()
             .map(|id| kwd("const").append(ident(id)).append(" = IDL.Rec();")),
     );
-    let defs = lines(def_list.iter().map(|id| {
+    let defs = lines(def_list.iter().filter(|id| **id != "blob").map(|id| {
         let ty = env.find_type(id).unwrap();
         if recs.contains(id) {
             ident(id)

rust/candid_parser/src/bindings/motoko.rs

@@ -112,10 +112,15 @@ fn pp_ty(ty: &Type) -> RcDoc {
         Text => str("Text"),
         Reserved => str("Any"),
         Empty => str("None"),
-        Var(ref s) => escape(s, false),
+        Var(ref s) => {
+            if s == "blob" {
+                str("Blob")
+            } else {
+                escape(s, false)
+            }
+        }
         Principal => str("Principal"),
         Opt(ref t) => str("?").append(pp_ty(t)),
-        Vec(ref t) if matches!(t.as_ref(), Nat8) => str("Blob"),
         Vec(ref t) => enclose("[", pp_ty(t), "]"),
         Record(ref fs) => {
             if is_tuple(ty) {
@@ -220,13 +225,18 @@ fn pp_service(serv: &[(String, Type)]) -> RcDoc {
 }
 
 fn pp_defs(env: &TypeEnv) -> RcDoc {
-    lines(env.0.iter().map(|(id, ty)| {
-        kwd("public type")
-            .append(escape(id, false))
-            .append(" = ")
-            .append(pp_ty(ty))
-            .append(";")
-    }))
+    lines(
+        env.0
+            .iter()
+            .filter(|(id, _)| *id != "blob")
+            .map(|(id, ty)| {
+                kwd("public type")
+                    .append(escape(id, false))
+                    .append(" = ")
+                    .append(pp_ty(ty))
+                    .append(";")
+            }),
+    )
 }
 
 fn pp_actor(ty: &Type) -> RcDoc {

rust/candid_parser/src/bindings/rust.rs

@@ -123,11 +123,15 @@ fn pp_ty<'a>(ty: &'a Type, recs: &RecPoints) -> RcDoc<'a> {
         Reserved => str("candid::Reserved"),
         Empty => str("candid::Empty"),
         Var(ref id) => {
-            let name = ident(id, Some(Case::Pascal));
-            if recs.contains(id.as_str()) {
-                str("Box<").append(name).append(">")
+            if id == "blob" {
+                str("serde_bytes::ByteBuf")
             } else {
-                name
+                let name = ident(id, Some(Case::Pascal));
+                if recs.contains(id.as_str()) {
+                    str("Box<").append(name).append(">")
+                } else {
+                    name
+                }
             }
         }
         Principal => str("Principal"),
@@ -219,7 +223,7 @@ fn pp_defs<'a>(
     } else {
         &config.type_attributes
     };
-    lines(def_list.iter().map(|id| {
+    lines(def_list.iter().filter(|id| **id != "blob").map(|id| {
         let ty = env.find_type(id).unwrap();
         let name = ident(id, Some(Case::Pascal)).append(" ");
         let vis = "pub ";

rust/candid_parser/src/bindings/typescript.rs

@@ -24,7 +24,9 @@ fn pp_ty<'a>(env: &'a TypeEnv, ty: &'a Type, is_ref: bool) -> RcDoc<'a> {
         Reserved => str("any"),
         Empty => str("never"),
         Var(ref id) => {
-            if is_ref {
+            if id == "blob" {
+                str("Uint8Array | number[]")
+            } else if is_ref {
                 let ty = env.rec_find_type(id).unwrap();
                 if matches!(ty.as_ref(), Service(_) | Func(_)) {
                     pp_ty(env, ty, false)
@@ -142,7 +144,7 @@ fn pp_service<'a>(env: &'a TypeEnv, serv: &'a [(String, Type)]) -> RcDoc<'a> {
 }
 
 fn pp_defs<'a>(env: &'a TypeEnv, def_list: &'a [&'a str]) -> RcDoc<'a> {
-    lines(def_list.iter().map(|id| {
+    lines(def_list.iter().filter(|id| **id != "blob").map(|id| {
         let ty = env.find_type(id).unwrap();
         let export = match ty.as_ref() {
             TypeInner::Record(_) if !ty.is_tuple() => kwd("export interface")

rust/candid_parser/src/grammar.lalrpop

@@ -165,7 +165,7 @@ pub Typ: IDLType = {
     PrimTyp => <>,
     "opt" <Typ> => IDLType::OptT(Box::new(<>)),
     "vec" <Typ> => IDLType::VecT(Box::new(<>)),
-    "blob" => IDLType::VecT(Box::new(IDLType::PrimT(PrimType::Nat8))),
+    "blob" => IDLType::VarT("blob".to_string()),
     "record" "{" <Sp<SepBy<RecordFieldTyp, ";">>> "}" =>? {
         let mut id: u32 = 0;
         let span = <>.1.clone();

rust/candid_parser/tests/assets/ok/example.did

@@ -29,7 +29,7 @@ type tree = variant {
 service : {
   bbbbb : (b) -> ();
   f : t;
-  f1 : (list, vec nat8, opt bool) -> () oneway;
+  f1 : (list, blob, opt bool) -> () oneway;
   g : (list) -> (B, tree, stream);
   g1 : (my_type, List, opt List, nested) -> (int, broker) query;
   h : (vec opt text, variant { A : nat; B : opt text }, opt List) -> (

rust/candid_parser/tests/assets/ok/keyword.did

@@ -15,9 +15,9 @@ service : {
   fieldnat : (record { 2 : int; "2" : nat }) -> (record { int });
   "oneway" : (nat8) -> () oneway;
   oneway_ : (nat8) -> () oneway;
-  "query" : (vec nat8) -> (vec nat8) query;
+  "query" : (blob) -> (blob) query;
   return : (o) -> (o);
   "service" : t;
-  tuple : (record { int; vec nat8; text }) -> (record { int; nat8 });
+  tuple : (record { int; blob; text }) -> (record { int; nat8 });
   "variant" : (variant { A; B; C; D : float64 }) -> ();
 }

rust/candid_parser/tests/assets/ok/management.did

@@ -1,6 +1,6 @@
 type bitcoin_address = text;
 type bitcoin_network = variant { mainnet; testnet };
-type block_hash = vec nat8;
+type block_hash = blob;
 type canister_id = principal;
 type canister_settings = record {
   freezing_threshold : opt nat;
@@ -23,31 +23,31 @@ type get_balance_request = record {
 type get_current_fee_percentiles_request = record { network : bitcoin_network };
 type get_utxos_request = record {
   network : bitcoin_network;
-  filter : opt variant { page : vec nat8; min_confirmations : nat32 };
+  filter : opt variant { page : blob; min_confirmations : nat32 };
   address : bitcoin_address;
 };
 type get_utxos_response = record {
-  next_page : opt vec nat8;
+  next_page : opt blob;
   tip_height : nat32;
   tip_block_hash : block_hash;
   utxos : vec utxo;
 };
 type http_header = record { value : text; name : text };
 type http_response = record {
   status : nat;
-  body : vec nat8;
+  body : blob;
   headers : vec http_header;
 };
 type millisatoshi_per_byte = nat64;
-type outpoint = record { txid : vec nat8; vout : nat32 };
+type outpoint = record { txid : blob; vout : nat32 };
 type satoshi = nat64;
 type send_transaction_request = record {
-  transaction : vec nat8;
+  transaction : blob;
   network : bitcoin_network;
 };
 type user_id = principal;
 type utxo = record { height : nat32; value : satoshi; outpoint : outpoint };
-type wasm_module = vec nat8;
+type wasm_module = blob;
 service : {
   bitcoin_get_balance : (get_balance_request) -> (satoshi);
   bitcoin_get_current_fee_percentiles : (
@@ -62,7 +62,7 @@ service : {
         cycles : nat;
         settings : definite_canister_settings;
         idle_cycles_burned_per_day : nat;
-        module_hash : opt vec nat8;
+        module_hash : opt blob;
       },
     );
   create_canister : (record { settings : opt canister_settings }) -> (
@@ -74,27 +74,27 @@ service : {
       record {
         key_id : record { name : text; curve : ecdsa_curve };
         canister_id : opt canister_id;
-        derivation_path : vec vec nat8;
+        derivation_path : vec blob;
       },
-    ) -> (record { public_key : vec nat8; chain_code : vec nat8 });
+    ) -> (record { public_key : blob; chain_code : blob });
   http_request : (
       record {
         url : text;
         method : variant { get; head; post };
         max_response_bytes : opt nat64;
-        body : opt vec nat8;
+        body : opt blob;
         transform : opt record {
           function : func (
-              record { context : vec nat8; response : http_response },
+              record { context : blob; response : http_response },
             ) -> (http_response) query;
-          context : vec nat8;
+          context : blob;
         };
         headers : vec http_header;
       },
     ) -> (http_response);
   install_code : (
       record {
-        arg : vec nat8;
+        arg : blob;
         wasm_module : wasm_module;
         mode : variant { reinstall; upgrade; install };
         canister_id : canister_id;
@@ -110,14 +110,14 @@ service : {
   provisional_top_up_canister : (
       record { canister_id : canister_id; amount : nat },
     ) -> ();
-  raw_rand : () -> (vec nat8);
+  raw_rand : () -> (blob);
   sign_with_ecdsa : (
       record {
         key_id : record { name : text; curve : ecdsa_curve };
-        derivation_path : vec vec nat8;
-        message_hash : vec nat8;
+        derivation_path : vec blob;
+        message_hash : blob;
       },
-    ) -> (record { signature : vec nat8 });
+    ) -> (record { signature : blob });
   start_canister : (record { canister_id : canister_id }) -> ();
   stop_canister : (record { canister_id : canister_id }) -> ();
   uninstall_code : (record { canister_id : canister_id }) -> ();