From b854c78dde8658ffae0c0c1f1be5679fc3bb516c Mon Sep 17 00:00:00 2001
From: Ed Ball <ed@xsats.com>
Date: Sat, 28 Jan 2023 19:10:54 +0100
Subject: [PATCH] feat: expose get_internal_address

---
 bdk-ffi/src/bdk.udl   |  3 +++
 bdk-ffi/src/wallet.rs | 16 ++++++++++++++++
 2 files changed, 19 insertions(+)

diff --git a/bdk-ffi/src/bdk.udl b/bdk-ffi/src/bdk.udl
index f9c38b2..374ba64 100644
--- a/bdk-ffi/src/bdk.udl
+++ b/bdk-ffi/src/bdk.udl
@@ -212,6 +212,9 @@ interface Wallet {
   [Throws=BdkError]
   AddressInfo get_address(AddressIndex address_index);
 
+  [Throws=BdkError]
+  AddressInfo get_internal_address(AddressIndex address_index);
+
   [Throws=BdkError]
   Balance get_balance();
 
diff --git a/bdk-ffi/src/wallet.rs b/bdk-ffi/src/wallet.rs
index 29daf4b..a5ef145 100644
--- a/bdk-ffi/src/wallet.rs
+++ b/bdk-ffi/src/wallet.rs
@@ -88,6 +88,22 @@ impl Wallet {
             .map(AddressInfo::from)
     }
 
+    /// Return a derived address using the internal (change) descriptor.
+    ///
+    /// If the wallet doesn't have an internal descriptor it will use the external descriptor.
+    ///
+    /// see [`AddressIndex`] for available address index selection strategies. If none of the keys
+    /// in the descriptor are derivable (i.e. does not end with /*) then the same address will always
+    /// be returned for any [`AddressIndex`].
+    pub(crate) fn get_internal_address(
+        &self,
+        address_index: AddressIndex,
+    ) -> Result<AddressInfo, BdkError> {
+        self.get_wallet()
+            .get_internal_address(address_index.into())
+            .map(AddressInfo::from)
+    }
+
     /// Return the balance, meaning the sum of this wallet’s unspent outputs’ values. Note that this method only operates
     /// on the internal database, which first needs to be Wallet.sync manually.
     pub(crate) fn get_balance(&self) -> Result<Balance, BdkError> {