add type check

Author: myfreess

src/client/README.mbt.md

@@ -91,7 +91,7 @@ async fn _transaction_example(client : @client.Client) -> Unit {
 
 ## Errors
 
-Driver operations raise `ClientError`.
+Driver operations raise `ClientError`. Type mismatches detected before encoding or decoding raise `ClientError::WrongType`.
 
 ```mbt check
 ///|

src/client/client.mbt

@@ -1452,6 +1452,39 @@ fn execute_portal_bytes(portal_name : BytesView, max_rows : Int) -> Bytes raise
   buf.to_bytes()
 }
 
+///|
+priv struct EncodedParam {
+  format : Int
+  value : Bytes?
+}
+
+///|
+fn encode_param(param : &ToSql, type_ : Type) -> EncodedParam raise {
+  guard param.accepts(type_) else {
+    raise wrong_type_error(param.moonbit_type_name(), type_)
+  }
+  let payload = @buffer.new()
+  let value = match param.to_sql(type_, payload) {
+    @proto.IsNull::Yes => None
+    @proto.IsNull::No => Some(payload.to_bytes())
+  }
+  { format: param.format(type_), value }
+}
+
+///|
+fn write_encoded_param(
+  param : EncodedParam,
+  payload : @buffer.Buffer,
+) -> @proto.IsNull {
+  match param.value {
+    None => @proto.IsNull::Yes
+    Some(bytes) => {
+      payload.write_bytes(bytes)
+      @proto.IsNull::No
+    }
+  }
+}
+
 ///|
 fn write_bind(
   buf : @buffer.Buffer,
@@ -1461,14 +1494,17 @@ fn write_bind(
   params : Array[&ToSql],
   describe_portal : Bool,
 ) -> Unit raise {
-  let formats = params.mapi((index, param) => param.format(param_types[index]))
-  let values = params.mapi((index, param) => (param, param_types[index]))
+  let encoded_params : Array[EncodedParam] = []
+  for index, param in params {
+    encoded_params.push(encode_param(param, param_types[index]))
+  }
+  let formats = encoded_params.map(param => param.format)
   @frontend.bind(
     portal,
     statement,
     formats.iter(),
-    values.iter(),
-    (pair, payload) => serialize_param(pair.0, pair.1, payload),
+    encoded_params.iter(),
+    (param, payload) => write_encoded_param(param, payload),
     [1].iter(),
     buf,
   )
@@ -1691,17 +1727,6 @@ fn join_clauses(clauses : Array[String]) -> String {
   out
 }
 
-///|
-fn serialize_param(
-  param : &ToSql,
-  type_ : Type,
-  payload : @buffer.Buffer,
-) -> @proto.IsNull raise @proto.ProtocolError {
-  param.to_sql(type_, payload) catch {
-    err => raise @proto.ProtocolError::InvalidInput(err.to_string())
-  }
-}
-
 ///|
 async fn connect_stream(config : Config) -> Stream {
   let conn = @socket.Tcp::connect_to_host(config.host, port=config.port)

src/client/pkg.generated.mbti

@@ -18,7 +18,7 @@ pub suberror ClientError {
   Ssl(String)
   Encode(String)
   Decode(String)
-  WrongType(String)
+  WrongType(WrongTypeError)
   ColumnNotFound(String)
   RowCount(String)
   UnexpectedMessage(String)
@@ -209,7 +209,7 @@ pub async fn Transaction::commit(Self) -> Unit
 pub async fn Transaction::execute(Self, String, params? : Array[&ToSql]) -> Int
 pub async fn Transaction::prepare(Self, String) -> Statement
 pub async fn Transaction::query(Self, String, params? : Array[&ToSql]) -> RowStream
-pub async fn Transaction::query_portal(Self, Portal, Int) -> RowStream
+pub fn Transaction::query_portal(Self, Portal, Int) -> RowStream raise
 pub async fn Transaction::rollback(Self) -> Unit
 pub async fn Transaction::transaction(Self) -> Self
 
@@ -257,11 +257,18 @@ pub fn Type::uuid_array() -> Self
 pub fn Type::varchar() -> Self
 pub fn Type::varchar_array() -> Self
 
+pub struct WrongTypeError {
+  moonbit_type : String
+  postgres_type : Type
+} derive(Eq, Show)
+
 // Type aliases
 
 // Traits
 pub(open) trait FromSql {
   from_sql(Type, Int, BytesView) -> Self raise
+  accepts(Type) -> Bool
+  moonbit_type_name() -> String
   from_sql_null(Type, Int) -> Self raise = _
 }
 pub impl FromSql for Bool
@@ -276,6 +283,8 @@ pub impl FromSql for Bytes
 
 pub(open) trait ToSql {
   format(Self, Type) -> Int = _
+  accepts(Self, Type) -> Bool
+  moonbit_type_name(Self) -> String
   to_sql(Self, Type, @buffer.Buffer) -> @protocol.IsNull raise
 }
 pub impl ToSql for Bool