remove transfer with fee instruction (#3766)

Author: samkim-crypto

token/program-2022/src/extension/confidential_transfer/instruction.rs

@@ -201,28 +201,6 @@ pub enum ConfidentialTransferInstruction {
     ///
     Transfer,
 
-    /// Transfer tokens confidentially with fee.
-    ///
-    ///   * Single owner/delegate
-    ///   1. `[writable]` The source SPL Token account.
-    ///   2. `[writable]` The destination SPL Token account.
-    ///   3. `[]` The token mint.
-    ///   4. `[]` Instructions sysvar.
-    ///   5. `[signer]` The single source account owner.
-    ///
-    ///   * Multisignature owner/delegate
-    ///   1. `[writable]` The source SPL Token account.
-    ///   2. `[writable]` The destination SPL Token account.
-    ///   3. `[]` The token mint.
-    ///   4. `[]` Instructions sysvar.
-    ///   5. `[]` The multisig  source account owner.
-    ///   6.. `[signer]` Required M signer accounts for the SPL Token Multisig account.
-    ///
-    /// Data expected by this instruction:
-    ///   `TransferInstructionData`
-    ///
-    TransferWithFee,
-
     /// Applies the pending balance to the available balance, based on the history of `Deposit`
     /// and/or `Transfer` instructions.
     ///
@@ -418,8 +396,7 @@ pub struct WithdrawInstructionData {
     pub proof_instruction_offset: i8,
 }
 
-/// Data expected by `ConfidentialTransferInstruction::Transfer` and
-/// `ConfidentialTransferInstruction::TransferWithFee`
+/// Data expected by `ConfidentialTransferInstruction::Transfer`
 #[derive(Clone, Copy, Pod, Zeroable)]
 #[repr(C)]
 pub struct TransferInstructionData {
@@ -758,7 +735,7 @@ pub fn inner_transfer(
     ))
 }
 
-/// Create a `Transfer` instruction
+/// Create a `Transfer` instruction with regular (no-fee) proof
 #[allow(clippy::too_many_arguments)]
 #[cfg(not(target_os = "solana"))]
 pub fn transfer(
@@ -786,46 +763,7 @@ pub fn transfer(
     ])
 }
 
-/// Create a inner `TransferWithFee` instruction
-///
-/// This instruction is suitable for use with a cross-program `invoke`
-#[allow(clippy::too_many_arguments)]
-pub fn inner_transfer_with_fee(
-    token_program_id: &Pubkey,
-    source_token_account: &Pubkey,
-    destination_token_account: &Pubkey,
-    mint: &Pubkey,
-    new_source_decryptable_available_balance: DecryptableBalance,
-    authority: &Pubkey,
-    multisig_signers: &[&Pubkey],
-    proof_instruction_offset: i8,
-) -> Result<Instruction, ProgramError> {
-    check_program_account(token_program_id)?;
-    let mut accounts = vec![
-        AccountMeta::new(*source_token_account, false),
-        AccountMeta::new(*destination_token_account, false),
-        AccountMeta::new_readonly(*mint, false),
-        AccountMeta::new_readonly(sysvar::instructions::id(), false),
-        AccountMeta::new_readonly(*authority, multisig_signers.is_empty()),
-    ];
-
-    for multisig_signer in multisig_signers.iter() {
-        accounts.push(AccountMeta::new_readonly(**multisig_signer, true));
-    }
-
-    Ok(encode_instruction(
-        token_program_id,
-        accounts,
-        TokenInstruction::ConfidentialTransferExtension,
-        ConfidentialTransferInstruction::TransferWithFee,
-        &TransferInstructionData {
-            new_source_decryptable_available_balance,
-            proof_instruction_offset,
-        },
-    ))
-}
-
-/// Create a `Transfer` instruction
+/// Create a `Transfer` instruction with fee proof
 #[allow(clippy::too_many_arguments)]
 #[cfg(not(target_os = "solana"))]
 pub fn transfer_with_fee(
@@ -839,7 +777,7 @@ pub fn transfer_with_fee(
     proof_data: &TransferWithFeeData,
 ) -> Result<Vec<Instruction>, ProgramError> {
     Ok(vec![
-        inner_transfer_with_fee(
+        inner_transfer(
             token_program_id,
             source_token_account,
             destination_token_account,

token/program-2022/src/extension/confidential_transfer/processor.rs

@@ -1208,23 +1208,6 @@ pub(crate) fn process_instruction(
             #[cfg(not(feature = "zk-ops"))]
             Err(ProgramError::InvalidInstructionData)
         }
-        ConfidentialTransferInstruction::TransferWithFee => {
-            msg!("ConfidentialTransferInstruction::TransferWithFee");
-            #[cfg(feature = "zk-ops")]
-            {
-                let data = decode_instruction_data::<TransferInstructionData>(input)?;
-                process_transfer(
-                    program_id,
-                    accounts,
-                    data.new_source_decryptable_available_balance,
-                    data.proof_instruction_offset as i64,
-                )
-            }
-            #[cfg(not(feature = "zk-ops"))]
-            {
-                Err(ProgramError::InvalidInstructionData)
-            }
-        }
         ConfidentialTransferInstruction::ApplyPendingBalance => {
             msg!("ConfidentialTransferInstruction::ApplyPendingBalance");
             #[cfg(feature = "zk-ops")]