Add a ComputeHealth instruction

This way the client can ask for simulation to determine an account's
health.

programs/mango-v4/src/instructions/compute_health.rs

@@ -0,0 +1,21 @@
+use crate::state::*;
+use anchor_lang::prelude::*;
+use fixed::types::I80F48;
+
+#[derive(Accounts)]
+pub struct ComputeHealth<'info> {
+    pub group: AccountLoader<'info, Group>,
+
+    #[account(
+        has_one = group,
+    )]
+    pub account: AccountLoader<'info, MangoAccount>,
+}
+
+pub fn compute_health(ctx: Context<ComputeHealth>, health_type: HealthType) -> Result<I80F48> {
+    let account = ctx.accounts.account.load()?;
+    let health = compute_health_from_fixed_accounts(&account, health_type, ctx.remaining_accounts)?;
+    msg!("health: {}", health);
+
+    Ok(health)
+}

programs/mango-v4/src/instructions/mod.rs

@@ -3,6 +3,7 @@ pub use benchmark::*;
 pub use close_account::*;
 pub use close_group::*;
 pub use close_stub_oracle::*;
+pub use compute_health::*;
 pub use create_account::*;
 pub use create_group::*;
 pub use create_stub_oracle::*;
@@ -36,6 +37,7 @@ mod benchmark;
 mod close_account;
 mod close_group;
 mod close_stub_oracle;
+mod compute_health;
 mod create_account;
 mod create_group;
 mod create_stub_oracle;

programs/mango-v4/src/lib.rs

@@ -17,7 +17,9 @@ mod serum3_cpi;
 pub mod state;
 pub mod types;
 
-use state::{OracleConfig, OrderType, PerpMarketIndex, Serum3MarketIndex, Side, TokenIndex};
+use state::{
+    HealthType, OracleConfig, OrderType, PerpMarketIndex, Serum3MarketIndex, Side, TokenIndex,
+};
 
 declare_id!("m43thNJ58XCjL798ZSq6JGAG1BnWskhdq5or6kcnfsD");
 
@@ -340,6 +342,10 @@ pub mod mango_v4 {
 
     // resolve_banktruptcy
 
+    pub fn compute_health(ctx: Context<ComputeHealth>, health_type: HealthType) -> Result<I80F48> {
+        instructions::compute_health(ctx, health_type)
+    }
+
     ///
     /// benchmark
     ///

programs/mango-v4/src/state/health.rs

@@ -258,7 +258,7 @@ impl<'a, 'info> AccountRetriever for ScanningAccountRetriever<'a, 'info> {
 /// slightly smaller weights for the liabilities. Zero is used as the bright line for both
 /// i.e. if your init health falls below zero, you cannot open new positions and if your maint. health
 /// falls below zero you will be liquidated.
-#[derive(PartialEq, Copy, Clone)]
+#[derive(PartialEq, Copy, Clone, AnchorSerialize, AnchorDeserialize)]
 pub enum HealthType {
     Init,
     Maint,

programs/mango-v4/tests/program_test/mango_client.rs

@@ -2059,3 +2059,47 @@ impl ClientInstruction for UpdateIndexInstruction {
         vec![]
     }
 }
+
+pub struct ComputeHealthInstruction {
+    pub account: Pubkey,
+    pub health_type: HealthType,
+}
+#[async_trait::async_trait(?Send)]
+impl ClientInstruction for ComputeHealthInstruction {
+    type Accounts = mango_v4::accounts::ComputeHealth;
+    type Instruction = mango_v4::instruction::ComputeHealth;
+    async fn to_instruction(
+        &self,
+        account_loader: impl ClientAccountLoader + 'async_trait,
+    ) -> (Self::Accounts, instruction::Instruction) {
+        let program_id = mango_v4::id();
+        let instruction = Self::Instruction {
+            health_type: self.health_type,
+        };
+
+        let account: MangoAccount = account_loader.load(&self.account).await.unwrap();
+
+        let health_check_metas = derive_health_check_remaining_account_metas(
+            &account_loader,
+            &account,
+            None,
+            false,
+            None,
+        )
+        .await;
+
+        let accounts = Self::Accounts {
+            group: account.group,
+            account: self.account,
+        };
+
+        let mut instruction = make_instruction(program_id, &accounts, instruction);
+        instruction.accounts.extend(health_check_metas.into_iter());
+
+        (accounts, instruction)
+    }
+
+    fn signers(&self) -> Vec<&Keypair> {
+        vec![]
+    }
+}

programs/mango-v4/tests/test_basic.rs

@@ -84,6 +84,19 @@ async fn test_basic() -> Result<(), TransportError> {
         );
     }
 
+    //
+    // TEST: Compute the account health
+    //
+    send_tx(
+        solana,
+        ComputeHealthInstruction {
+            account,
+            health_type: HealthType::Init,
+        },
+    )
+    .await
+    .unwrap();
+
     //
     // TEST: Withdraw funds
     //