Expose which keys signed the Transaction in the SDK

sdk/src/account.rs

@@ -33,19 +33,50 @@ impl Account {
 #[repr(C)]
 #[derive(Debug)]
 pub struct KeyedAccount<'a> {
-    pub key: &'a Pubkey,
+    is_signer: bool, // Transaction was signed by this account's key
+    key: &'a Pubkey,
     pub account: &'a mut Account,
 }
 
+impl<'a> KeyedAccount<'a> {
+    pub fn signer_key(&self) -> Option<&Pubkey> {
+        if self.is_signer {
+            Some(self.key)
+        } else {
+            None
+        }
+    }
+
+    pub fn unsigned_key(&self) -> &Pubkey {
+        self.key
+    }
+
+    pub fn new(key: &'a Pubkey, is_signer: bool, account: &'a mut Account) -> KeyedAccount<'a> {
+        KeyedAccount {
+            key,
+            is_signer,
+            account,
+        }
+    }
+}
+
 impl<'a> From<(&'a Pubkey, &'a mut Account)> for KeyedAccount<'a> {
     fn from((key, account): (&'a Pubkey, &'a mut Account)) -> Self {
-        KeyedAccount { key, account }
+        KeyedAccount {
+            is_signer: false,
+            key,
+            account,
+        }
     }
 }
 
 impl<'a> From<&'a mut (Pubkey, Account)> for KeyedAccount<'a> {
     fn from((key, account): &'a mut (Pubkey, Account)) -> Self {
-        KeyedAccount { key, account }
+        KeyedAccount {
+            is_signer: false,
+            key,
+            account,
+        }
     }
 }
 

sdk/src/transaction.rs

@@ -126,7 +126,7 @@ impl Transaction {
         self.key_index(instruction_index, accounts_index)
             .and_then(|account_keys_index| self.account_keys.get(account_keys_index))
     }
-    pub fn signed_key(&self, instruction_index: usize, accounts_index: usize) -> Option<&Pubkey> {
+    pub fn signer_key(&self, instruction_index: usize, accounts_index: usize) -> Option<&Pubkey> {
         match self.key_index(instruction_index, accounts_index) {
             None => None,
             Some(signature_index) => {
@@ -232,22 +232,22 @@ mod tests {
         assert!(tx.verify_refs());
 
         assert_eq!(tx.key(0, 0), Some(&key.pubkey()));
-        assert_eq!(tx.signed_key(0, 0), Some(&key.pubkey()));
+        assert_eq!(tx.signer_key(0, 0), Some(&key.pubkey()));
 
         assert_eq!(tx.key(1, 0), Some(&key.pubkey()));
-        assert_eq!(tx.signed_key(1, 0), Some(&key.pubkey()));
+        assert_eq!(tx.signer_key(1, 0), Some(&key.pubkey()));
 
         assert_eq!(tx.key(0, 1), Some(&key1));
-        assert_eq!(tx.signed_key(0, 1), None);
+        assert_eq!(tx.signer_key(0, 1), None);
 
         assert_eq!(tx.key(1, 1), Some(&key2));
-        assert_eq!(tx.signed_key(1, 1), None);
+        assert_eq!(tx.signer_key(1, 1), None);
 
         assert_eq!(tx.key(2, 0), None);
-        assert_eq!(tx.signed_key(2, 0), None);
+        assert_eq!(tx.signer_key(2, 0), None);
 
         assert_eq!(tx.key(0, 2), None);
-        assert_eq!(tx.signed_key(0, 2), None);
+        assert_eq!(tx.signer_key(0, 2), None);
 
         assert_eq!(*tx.program_id(0), prog1);
         assert_eq!(*tx.program_id(1), prog2);