make sure fields are not present when tip is 0

zebra-rpc/src/methods/get_block_template_rpcs.rs

@@ -1017,22 +1017,29 @@ where
         let chain_tip = self.latest_chain_tip.clone();
         let tip_height = chain_tip.best_tip_height().unwrap_or(Height(0)).0;
 
-        let mined_tx_ids = chain_tip.best_tip_mined_transaction_ids();
-        let current_block_tx = (!mined_tx_ids.is_empty()).then(|| mined_tx_ids.len());
+        let mut current_block_tx = None;
+        if tip_height > 0 {
+            let mined_tx_ids = chain_tip.best_tip_mined_transaction_ids();
+            current_block_tx =
+                (!mined_tx_ids.is_empty()).then(|| mined_tx_ids.len().saturating_sub(1));
+        }
 
         let solution_rate_fut = self.get_network_sol_ps(None, None);
         async move {
             // Get the current block size.
-            let request = zebra_state::ReadRequest::TipBlockSize;
-            let response: zebra_state::ReadResponse = state
-                .ready()
-                .and_then(|service| service.call(request))
-                .await
-                .map_server_error()?;
-            let current_block_size = match response {
-                zebra_state::ReadResponse::TipBlockSize(Some(block_size)) => Some(block_size),
-                _ => None,
-            };
+            let mut current_block_size = None;
+            if tip_height > 0 {
+                let request = zebra_state::ReadRequest::TipBlockSize;
+                let response: zebra_state::ReadResponse = state
+                    .ready()
+                    .and_then(|service| service.call(request))
+                    .await
+                    .map_server_error()?;
+                current_block_size = match response {
+                    zebra_state::ReadResponse::TipBlockSize(Some(block_size)) => Some(block_size),
+                    _ => None,
+                };
+            }
 
             Ok(get_mining_info::Response::new(
                 tip_height,