Fail on incorrect parameter count

Author: sfackler

src/lib.rs

@@ -573,6 +573,9 @@ impl<'self> NormalPostgresStatement<'self> {
             -> Option<PostgresDbError> {
         let mut formats = ~[];
         let mut values = ~[];
+        assert!(self.param_types.len() == params.len(),
+                "Expected %u parameters but found %u",
+                self.param_types.len(), params.len());
         for (&param, &ty) in params.iter().zip(self.param_types.iter()) {
             let (format, value) = param.to_sql(ty);
             formats.push(format as i16);

src/test.rs

@@ -311,6 +311,22 @@ fn test_wrong_param_type() {
     conn.try_update("SELECT $1::VARCHAR", [&1i32 as &ToSql]);
 }
 
+#[test]
+#[should_fail]
+fn test_too_few_params() {
+    let conn = PostgresConnection::connect("postgres://postgres@localhost");
+    conn.try_update("SELECT $1::INT, $2::INT", [&1i32 as &ToSql]);
+}
+
+#[test]
+#[should_fail]
+fn test_too_many_params() {
+    let conn = PostgresConnection::connect("postgres://postgres@localhost");
+    conn.try_update("SELECT $1::INT, $2::INT", [&1i32 as &ToSql,
+                                               &2i32 as &ToSql,
+                                               &3i32 as &ToSql]);
+}
+
 #[test]
 fn test_find_col_named() {
     let conn = PostgresConnection::connect("postgres://postgres@localhost");