Add new preferred transaction constructors

sdk/src/transaction.rs

@@ -200,14 +200,15 @@ impl Transaction {
         transaction.recent_blockhash = recent_blockhash;
         transaction
     }
+
     /// Create a signed transaction
-    /// * `from_keypair` - The key used to sign the transaction.  This key is stored as keys[0]
+    /// * `from_keypairs` - The keys used to sign the transaction.
     /// * `account_keys` - The keys for the transaction.  These are the program state
     ///    instances or lamport recipient keys.
     /// * `recent_blockhash` - The PoH hash.
     /// * `fee` - The transaction fee.
     /// * `program_ids` - The keys that identify programs used in the `instruction` vector.
-    /// * `instructions` - The programs and their arguments that the transaction will execute atomically
+    /// * `instructions` - Instructions that will be executed atomically.
     pub fn new_with_instructions<T: KeypairUtil>(
         from_keypairs: &[&T],
         keys: &[Pubkey],
@@ -232,6 +233,7 @@ impl Transaction {
         tx.sign(from_keypairs, recent_blockhash);
         tx
     }
+
     pub fn data(&self, instruction_index: usize) -> &[u8] {
         &self.instructions[instruction_index].data
     }

sdk/src/transaction_builder.rs

@@ -50,6 +50,20 @@ impl TransactionBuilder {
         }
     }
 
+    /// Create a new unsigned transaction from a single instruction
+    pub fn new_singleton(instruction: BuilderInstruction) -> Transaction {
+        Self::default().push(instruction).compile()
+    }
+
+    /// Create a new unsigned transaction from a single instruction
+    pub fn new_with_instructions(instructions: Vec<BuilderInstruction>) -> Transaction {
+        let mut transaction_builder = Self::default();
+        for instruction in instructions {
+            transaction_builder.push(instruction);
+        }
+        transaction_builder.compile()
+    }
+
     /// Add an instruction.
     pub fn push(&mut self, instruction: BuilderInstruction) -> &mut Self {
         self.instructions.push(instruction);
@@ -240,4 +254,25 @@ mod tests {
         assert_eq!(tx.instructions[1], Instruction::new(1, &0, vec![0]));
         assert_eq!(tx.instructions[2], Instruction::new(0, &0, vec![0]));
     }
+
+    #[test]
+    fn test_transaction_builder_new_singleton() {
+        let ix = Instruction::new(Pubkey::default(), &0, vec![]);
+        assert_eq!(
+            TransactionBuilder::new_singleton(ix.clone()),
+            TransactionBuilder::default().push(ix.clone()).compile()
+        );
+    }
+
+    #[test]
+    fn test_transaction_builder_new_with_instructions() {
+        let ix = Instruction::new(Pubkey::default(), &0, vec![]);
+        assert_eq!(
+            TransactionBuilder::new_with_instructions(vec![ix.clone(), ix.clone()]),
+            TransactionBuilder::default()
+                .push(ix.clone())
+                .push(ix.clone())
+                .compile()
+        );
+    }
 }