From c55974dd010f62391b9cf9053d0d29a58c6c0bce Mon Sep 17 00:00:00 2001
From: Ivan Kalinin <i.kalinin@dexpa.io>
Date: Tue, 14 Nov 2023 16:04:12 +0100
Subject: [PATCH] Add `FromAbiIter` trait

---
 src/abi/mod.rs    |  3 ++-
 src/abi/traits.rs | 28 ++++++++++++++++++++++++++++
 2 files changed, 30 insertions(+), 1 deletion(-)

diff --git a/src/abi/mod.rs b/src/abi/mod.rs
index a2e419fa..602c2503 100644
--- a/src/abi/mod.rs
+++ b/src/abi/mod.rs
@@ -9,7 +9,8 @@ pub use self::contract::{
 };
 pub use self::signature::{extend_signature_with_id, sign_with_signature_id};
 pub use self::traits::{
-    FromAbi, FromPlainAbi, IgnoreName, IntoAbi, IntoPlainAbi, WithAbiType, WithPlainAbiType,
+    FromAbi, FromAbiIter, FromPlainAbi, IgnoreName, IntoAbi, IntoPlainAbi, WithAbiType,
+    WithPlainAbiType,
 };
 pub use self::ty::{AbiHeaderType, AbiType, NamedAbiType, PlainAbiType};
 pub use self::value::{AbiHeader, AbiValue, NamedAbiValue, PlainAbiValue};
diff --git a/src/abi/traits.rs b/src/abi/traits.rs
index da81d35e..2aaafb05 100644
--- a/src/abi/traits.rs
+++ b/src/abi/traits.rs
@@ -1131,6 +1131,34 @@ impl<T: FromAbi> FromAbi for Rc<T> {
     }
 }
 
+/// A wrapper around ABI values iterator that converts
+/// each item using the [`FromAbi`] trait.
+///
+/// It should be used to parse fields as tuple items
+/// for some struct `T` (which must implement [`WithAbiType`]).
+pub trait FromAbiIter<T> {
+    /// Advances the iterator and returns the next value.
+    fn next_value<V: FromAbi>(&mut self) -> Result<V>;
+}
+
+impl<T, I> FromAbiIter<T> for I
+where
+    T: WithAbiType,
+    I: Iterator<Item = AbiValue>,
+{
+    fn next_value<V: FromAbi>(&mut self) -> Result<V> {
+        match Iterator::next(self) {
+            Some(value) => V::from_abi(value),
+            None => Err(anyhow::Error::from(
+                crate::abi::error::AbiError::TypeMismatch {
+                    expected: T::abi_type().to_string().into_boxed_str(),
+                    ty: Box::from("tuple part"),
+                },
+            )),
+        }
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use ahash::HashSet;