Add transfer_vault_depositor_shares instruction

programs/drift_vaults/src/instructions/mod.rs

@@ -36,6 +36,7 @@ pub use reset_delegate::*;
 pub use reset_fuel_season::*;
 pub use reset_vault_fuel_season::*;
 pub use tokenize_shares::*;
+pub use transfer_vault_depositor_shares::*;
 pub use update_cumulative_fuel_amount::*;
 pub use update_delegate::*;
 pub use update_margin_trading_enabled::*;
@@ -84,6 +85,7 @@ mod reset_delegate;
 mod reset_fuel_season;
 mod reset_vault_fuel_season;
 mod tokenize_shares;
+mod transfer_vault_depositor_shares;
 mod update_cumulative_fuel_amount;
 mod update_delegate;
 mod update_margin_trading_enabled;

programs/drift_vaults/src/instructions/transfer_vault_depositor_shares.rs

@@ -0,0 +1,128 @@
+use anchor_lang::prelude::*;
+use drift::instructions::optional_accounts::AccountMaps;
+use drift::math::safe_math::SafeMath;
+use drift::state::user::User;
+
+use crate::constraints::{
+    is_authority_for_vault_depositor, is_user_for_vault, is_vault_for_vault_depositor,
+};
+use crate::error::ErrorCode;
+use crate::state::traits::VaultDepositorBase;
+use crate::{validate, AccountMapProvider};
+use crate::{Vault, VaultDepositor, VaultProtocolProvider, WithdrawUnit};
+
+pub fn transfer_vault_depositor_shares<'info>(
+    ctx: Context<'_, '_, 'info, 'info, TransferVaultDepositorShares<'info>>,
+    amount: u64,
+    withdraw_unit: WithdrawUnit,
+) -> Result<()> {
+    let clock = &Clock::get()?;
+
+    let mut vault = ctx.accounts.vault.load_mut()?;
+
+    validate!(!vault.in_liquidation(), ErrorCode::OngoingLiquidation)?;
+
+    validate!(
+        ctx.accounts.vault_depositor.key() != ctx.accounts.to_vault_depositor.key(),
+        ErrorCode::InvalidVaultDeposit,
+        "Cannot transfer shares to the same depositor"
+    )?;
+
+    validate!(
+        amount > 0,
+        ErrorCode::InvalidVaultWithdrawSize,
+        "Transfer amount must be greater than 0"
+    )?;
+
+    let mut vault_depositor = ctx.accounts.vault_depositor.load_mut()?;
+    let mut to_vault_depositor = ctx.accounts.to_vault_depositor.load_mut()?;
+
+    // backwards compatible: if last rem acct does not deserialize into [`VaultProtocol`] then it's a legacy vault.
+    let mut vp = ctx.vault_protocol();
+    vault.validate_vault_protocol(&vp)?;
+    let mut vp = vp.as_mut().map(|vp| vp.load_mut()).transpose()?;
+
+    let user = ctx.accounts.drift_user.load()?;
+    let spot_market_index = vault.spot_market_index;
+
+    let AccountMaps {
+        perp_market_map,
+        spot_market_map,
+        mut oracle_map,
+    } = ctx.load_maps(
+        clock.slot,
+        Some(spot_market_index),
+        vp.is_some(),
+        false,
+        false,
+    )?;
+
+    let vault_equity =
+        vault.calculate_equity(&user, &perp_market_map, &spot_market_map, &mut oracle_map)?;
+
+    validate!(
+        !vault_depositor.last_withdraw_request.pending(),
+        ErrorCode::InvalidVaultDeposit,
+        "Cannot transfer shares with a pending withdraw request"
+    )?;
+
+    validate!(
+        !to_vault_depositor.last_withdraw_request.pending(),
+        ErrorCode::InvalidVaultDeposit,
+        "Cannot transfer shares to a depositor with a pending withdraw request"
+    )?;
+
+    let spot_market = spot_market_map.get_ref(&spot_market_index)?;
+    let oracle = oracle_map.get_price_data(&spot_market.oracle_id())?;
+
+    let total_shares_before = vault_depositor
+        .get_vault_shares()
+        .safe_add(to_vault_depositor.get_vault_shares())?;
+
+    vault_depositor.transfer_shares(
+        &mut *to_vault_depositor,
+        &mut vault,
+        &mut vp,
+        &mut None,
+        amount,
+        withdraw_unit,
+        vault_equity,
+        clock.unix_timestamp,
+        oracle.price,
+    )?;
+
+    let total_shares_after = vault_depositor
+        .get_vault_shares()
+        .safe_add(to_vault_depositor.get_vault_shares())?;
+
+    validate!(
+        total_shares_after.eq(&total_shares_before),
+        ErrorCode::InvalidVaultSharesDetected,
+        "Total vault depositor shares before != after"
+    )?;
+
+    Ok(())
+}
+
+#[derive(Accounts)]
+pub struct TransferVaultDepositorShares<'info> {
+    #[account(mut)]
+    pub vault: AccountLoader<'info, Vault>,
+    #[account(
+        mut,
+        seeds = [b"vault_depositor", vault.key().as_ref(), authority.key().as_ref()],
+        bump,
+        constraint = is_authority_for_vault_depositor(&vault_depositor, &authority)?,
+    )]
+    pub vault_depositor: AccountLoader<'info, VaultDepositor>,
+    pub authority: Signer<'info>,
+    #[account(
+        mut,
+        constraint = is_vault_for_vault_depositor(&to_vault_depositor, &vault)?,
+    )]
+    pub to_vault_depositor: AccountLoader<'info, VaultDepositor>,
+    #[account(
+        constraint = is_user_for_vault(&vault, &drift_user.key())?
+    )]
+    pub drift_user: AccountLoader<'info, User>,
+}

programs/drift_vaults/src/lib.rs

@@ -310,6 +310,14 @@ pub mod drift_vaults {
         instructions::cancel_request_remove_insurance_fund_stake(ctx, market_index)
     }
 
+    pub fn transfer_vault_depositor_shares<'info>(
+        ctx: Context<'_, '_, 'info, 'info, TransferVaultDepositorShares<'info>>,
+        amount: u64,
+        withdraw_unit: WithdrawUnit,
+    ) -> Result<()> {
+        instructions::transfer_vault_depositor_shares(ctx, amount, withdraw_unit)
+    }
+
     pub fn protocol_request_withdraw<'c: 'info, 'info>(
         ctx: Context<'_, '_, 'c, 'info, ProtocolRequestWithdraw<'info>>,
         withdraw_amount: u64,

programs/drift_vaults/src/state/traits.rs

@@ -307,8 +307,8 @@ pub trait VaultDepositorBase {
         let to_depositor_shares_after = to.checked_vault_shares(vault)?;
 
         validate!(
-            from_depositor_shares_before.safe_add(to_depositor_shares_before)
-                == from_depositor_shares_after.safe_add(to_depositor_shares_after),
+            from_depositor_shares_before.safe_add(to_depositor_shares_before)?
+                == from_depositor_shares_after.safe_add(to_depositor_shares_after)?,
             ErrorCode::InvalidVaultSharesDetected,
             "VaultDepositor: total shares mismatch"
         )?;