Do message payment within same instruction

Change-Id: Id1e3ac10bcdc7e91c649f5e75caf8a98e27be0c6

solana/bridge/program/src/api/post_message.rs

@@ -64,9 +64,10 @@ impl<'b> InstructionContext<'b> for PostMessage<'b> {
 
 #[derive(BorshDeserialize, BorshSerialize, Default)]
 pub struct PostMessageData {
-    /// unique nonce for this message
+    /// Unique nonce for this message
     pub nonce: u32,
-    /// message payload
+
+    /// Message payload
     pub payload: Vec<u8>,
 }
 
@@ -84,7 +85,7 @@ pub fn post_message(
         payload: data.payload.clone(),
     };
 
-    trace!("Verifying Message: {}, {}", accs.emitter.key, data.nonce,);
+    trace!("Verifying Message: {}, {}", accs.emitter.key, data.nonce);
 
     accs.message
         .verify_derivation(ctx.program_id, &msg_derivation)?;

solana/bridge/program/tests/common.rs

@@ -152,14 +152,21 @@ mod helpers {
     ) -> Pubkey {
         // Transfer money into the fee collector as it needs a balance/must exist.
         let fee_collector = FeeCollector::<'_>::key(None, program);
-        transfer(client, payer, &fee_collector, 10_000);
 
         // Capture the resulting message, later functions will need this.
         let (message_key, instruction) =
             instructions::post_message(*program, payer.pubkey(), emitter.pubkey(), nonce, data)
                 .unwrap();
 
-        execute(client, payer, &[payer, emitter], &[instruction]);
+        execute(
+            client,
+            payer,
+            &[payer, emitter],
+            &[
+                system_instruction::transfer(&payer.pubkey(), &fee_collector, 10_000),
+                instruction,
+            ],
+        );
 
         message_key
     }