Merge #31: Add BlockHeader::clear_witness and ::is_dynafed methods

3e7c7b1 Add BlockHeader::clear_witness method (Steven Roose)
8b0d786 Add BlockHeader::is_dynafed (Steven Roose)

Pull request description:

Top commit has no ACKs.

Tree-SHA512: df4b899bec11b24da2abcfeed2a81f607fb62e28159ad7c0aa1937101d847cd2dbf6531ba177eae274aed3301a523e24a947a90db1f8ece3d8e2fa23e8962cef

Author: jonasnick

src/block.rs

@@ -223,6 +223,32 @@ pub struct BlockHeader {
 serde_struct_impl!(BlockHeader, version, prev_blockhash, merkle_root, time, height, ext);
 
 impl BlockHeader {
+    /// Returns true if this is a block with dynamic federations enabled.
+    pub fn is_dynafed(&self) -> bool {
+        if let ExtData::Dynafed {
+            ..
+        } = self.ext
+        {
+            true
+        } else {
+            false
+        }
+    }
+
+    /// Remove the witness data of the block header.
+    /// This is all the data that can be removed without changing
+    /// the block hash.
+    pub fn clear_witness(&mut self) {
+        match &mut self.ext {
+            &mut ExtData::Proof { ref mut solution, .. } => {
+                *solution = Script::new();
+            },
+            &mut ExtData::Dynafed { ref mut signblock_witness, .. } => {
+                signblock_witness.clear();
+            },
+        }
+    }
+
     /// Calculate the root of the dynafed params. Returns [None] when not dynafed.
     pub fn calculate_dynafed_params_root(&self) -> Option<sha256::Midstate> {
         match self.ext {