final

src/descriptor/key.rs

@@ -12,6 +12,8 @@ use bitcoin::{
 
 use MiniscriptKey;
 
+// use crate::Descriptor;
+
 /// The MiniscriptKey corresponding to Descriptors. This can
 /// either be Single public key or a Xpub
 #[derive(Debug, Eq, PartialEq, Clone, Ord, PartialOrd, Hash)]
@@ -668,6 +670,11 @@ impl MiniscriptKey for DescriptorPublicKey {
     }
 }
 
+// impl Descriptor<DescriptorPublicKey> {
+//     /// derive a [`Descriptor`] with a concrete [`bitcoin::PublicKey`] at a given index
+//     /// You can use all the methods from descriptor trait on this
+// }
+
 #[cfg(test)]
 mod test {
     use super::{DescriptorKeyParseError, DescriptorPublicKey, DescriptorSecretKey};

src/descriptor/mod.rs

@@ -29,7 +29,7 @@ use std::{
     str::{self, FromStr},
 };
 
-use bitcoin::secp256k1;
+use bitcoin::secp256k1::{self, Secp256k1};
 use bitcoin::{self, Script};
 
 use self::checksum::verify_checksum;
@@ -537,6 +537,24 @@ impl Descriptor<DescriptorPublicKey> {
         self.translate_pk2_infallible(|pk| pk.clone().derive(index))
     }
 
+    /// derive a [`Descriptor`] with a concrete [`bitcoin::PublicKey`] at a given index
+    /// Removes all extended pubkeys and wildcards from the descriptor and only leaves
+    /// concrete [`bitcoin::PublicKey`]
+    ///
+    /// # Panics
+    ///
+    /// Panics if given an index ≥ 2^31
+    pub fn derive_desc<C: secp256k1::Verification>(
+        &self,
+        index: u32,
+        secp_ctx: Secp256k1<C>,
+    ) -> Result<Descriptor<bitcoin::PublicKey>, ConversionError> {
+        let derived = self
+            .derive(index)
+            .translate_pk2(|xpk| xpk.derive_public_key(&secp_ctx))?;
+        todo!()
+    }
+
     /// Parse a descriptor that may contain secret keys
     ///
     /// Internally turns every secret key found into the corresponding public key and then returns a