From 965e280bdb8ecb4f4273499d2245ba5e533f8b09 Mon Sep 17 00:00:00 2001
From: Andrew Bright <abright@users.noreply.github.com>
Date: Tue, 13 Sep 2022 12:57:35 +1000
Subject: [PATCH] wip better state reloading mechanism

---
 fil_fungible_token/src/token/mod.rs           |  7 ++++
 .../actors/basic_token_actor/Cargo.toml       |  1 -
 .../actors/basic_token_actor/src/lib.rs       | 36 +++++++------------
 .../fil_token_integration/tests/more_tests.rs |  2 +-
 4 files changed, 21 insertions(+), 25 deletions(-)

diff --git a/fil_fungible_token/src/token/mod.rs b/fil_fungible_token/src/token/mod.rs
index 395e2fe6..d4eac445 100644
--- a/fil_fungible_token/src/token/mod.rs
+++ b/fil_fungible_token/src/token/mod.rs
@@ -99,6 +99,13 @@ where
         self.state = state;
     }
 
+    /// Loads a fresh copy of the state from a blockstore from a given cid, replacing existing state
+    /// The old state is returned to enable comparisons and the like but can be safely dropped otherwise
+    pub fn load_replace(&mut self, cid: &Cid) -> Result<TokenState> {
+        let new_state = TokenState::load(&self.bs, cid)?;
+        Ok(std::mem::replace(self.state, new_state))
+    }
+
     /// Opens an atomic transaction on TokenState which allows a closure to make multiple
     /// modifications to the state tree.
     ///
diff --git a/testing/fil_token_integration/actors/basic_token_actor/Cargo.toml b/testing/fil_token_integration/actors/basic_token_actor/Cargo.toml
index 1557dc7b..978fe30b 100644
--- a/testing/fil_token_integration/actors/basic_token_actor/Cargo.toml
+++ b/testing/fil_token_integration/actors/basic_token_actor/Cargo.toml
@@ -5,7 +5,6 @@ repository = "https://github.com/helix-collective/filecoin"
 edition = "2021"
 
 [dependencies]
-cid = { version = "0.8.5", default-features = false }
 fvm_ipld_blockstore = { version = "0.1.1" }
 fvm_ipld_encoding = { version = "0.2.2" }
 fvm_sdk = { version = "2.0.0-alpha.2" }
diff --git a/testing/fil_token_integration/actors/basic_token_actor/src/lib.rs b/testing/fil_token_integration/actors/basic_token_actor/src/lib.rs
index 94fbdb6a..2cf71114 100644
--- a/testing/fil_token_integration/actors/basic_token_actor/src/lib.rs
+++ b/testing/fil_token_integration/actors/basic_token_actor/src/lib.rs
@@ -1,6 +1,5 @@
 mod util;
 
-use cid::Cid;
 use fil_fungible_token::runtime::blockstore::Blockstore;
 use fil_fungible_token::runtime::messaging::FvmMessenger;
 use fil_fungible_token::token::types::{
@@ -146,7 +145,8 @@ pub struct MintParams {
 impl Cbor for MintParams {}
 
 impl BasicToken<'_> {
-    fn mint(&mut self, params: MintParams) -> Result<(Cid, MintReturn), RuntimeError> {
+    fn mint(&mut self, params: MintParams) -> Result<MintReturn, RuntimeError> {
+        let owner = params.initial_owner;
         let (mut hook, ret) = self.util.mint(
             &caller_address(),
             &params.initial_owner,
@@ -160,7 +160,15 @@ impl BasicToken<'_> {
 
         hook.call(self.util.msg())?;
 
-        Ok((cid, ret))
+        let new_cid = sdk::sself::root().unwrap();
+        let ret = if cid == new_cid {
+            ret
+        } else {
+            self.util.load_replace(&new_cid).unwrap();
+            MintReturn { balance: self.balance_of(owner).unwrap(), supply: self.total_supply() }
+        };
+
+        Ok(ret)
     }
 }
 
@@ -288,26 +296,8 @@ pub fn invoke(params: u32) -> u32 {
                 3839021839 => {
                     // Mint
                     let params: MintParams = deserialize_params(params);
-                    let owner = params.initial_owner;
-                    let (cid, res) = token_actor.mint(params).unwrap();
-
-                    // TODO: we need to know if the cid changed. having mint return it kinda works but is messy
-                    // but we also can't reload state inside those calls
-                    let new_cid = sdk::sself::root().unwrap();
-                    if cid == new_cid {
-                        return_ipld(&res).unwrap()
-                    } else {
-                        token_state = Token::<_, FvmMessenger>::load_state(&bs, &root_cid).unwrap();
-                        token_actor = BasicToken {
-                            util: Token::wrap(bs, FvmMessenger::default(), 1, &mut token_state),
-                        };
-
-                        return_ipld(&MintReturn {
-                            balance: token_actor.balance_of(owner).unwrap(),
-                            supply: token_actor.total_supply(),
-                        })
-                        .unwrap()
-                    }
+                    let res = token_actor.mint(params).unwrap();
+                    return_ipld(&res).unwrap()
                 }
                 _ => {
                     sdk::vm::abort(
diff --git a/testing/fil_token_integration/tests/more_tests.rs b/testing/fil_token_integration/tests/more_tests.rs
index ed3df4d9..a1ed80e4 100644
--- a/testing/fil_token_integration/tests/more_tests.rs
+++ b/testing/fil_token_integration/tests/more_tests.rs
@@ -117,7 +117,7 @@ fn more_tests() {
     println!("minting return data {:#?}", &ret_val);
     let mint_result: MintReturn = ret_val.msg_receipt.return_data.deserialize().unwrap();
     // tokens were burned so supply reduces back to zero
-    println!("minted - total supply: {:?}", &mint_result.supply);
+    println!("minted - total supply: {:?}, balance: {:?}", &mint_result.supply, &mint_result.balance);
     assert_eq!(mint_result.supply, TokenAmount::from_atto(0));
 
     // check balance of test actor, should also be zero