Check the Gas Free function during the compilation of the Move module. (

#886)

* Check the Gas Free function during the compilation of the Move module.

* Check the gas_free function during module publishing.

* fix the ordering of verifier function

* execute the gas_validate and gas_charge_post function when use tx has been executed

* Add gas_free function to deduct module account fees and update test code.

* Fix error handling and code reuse.


* Report an error indicating that the definition of the gas_free function is incomplete.

* Fix the checking logic.

* Resolve the issue with executing the gas_free callback function.

---------

Co-authored-by: stevenlaw123 <[email protected]>

crates/rooch-framework/sources/transaction_validator.move

@@ -149,7 +149,7 @@ module rooch_framework::transaction_validator {
     fun post_execute(
         ctx: &mut Context,
     ) {
-        let sender = context::sender(ctx);
+        // let sender = context::sender(ctx);
 
         // Active the session key
 
@@ -161,11 +161,12 @@ module rooch_framework::transaction_validator {
 
         // Increment sequence number
         account::increment_sequence_number(ctx);
-        
+
         let tx_result = context::tx_result(ctx);
+        let gas_payment_account = tx_result::gas_payment_account(&tx_result);
         let gas_used = tx_result::gas_used(&tx_result);
         let gas = transaction_fee::calculate_gas(ctx, gas_used);
-        let gas_coin = gas_coin::deduct_gas(ctx, sender, gas);
+        let gas_coin = gas_coin::deduct_gas(ctx, gas_payment_account, gas);
         transaction_fee::deposit_fee(ctx, gas_coin);
     }
 }

examples/gas_free/Move.toml

@@ -0,0 +1,14 @@
+[package]
+name = "gas_payer"
+version = "0.0.1"
+
+[dependencies]
+MoveosStdlib = { local = "../../moveos/moveos-stdlib/moveos-stdlib" }
+
+[addresses]
+rooch_examples =  "_"
+moveos_std =  "0x2"
+rooch_framework =  "0x3"
+
+[dev-addresses]
+rooch_examples = "0x42"

examples/gas_free/sources/gas_free.move

@@ -0,0 +1,15 @@
+module rooch_examples::gas_payer {
+    use moveos_std::context::Context;
+
+    fun gas_validate_function(_ctx: &Context): bool{
+        true
+    }
+
+    fun gas_charge_post_function(_ctx: &mut Context, _gas_used: u128): bool {
+        true
+    }
+
+    #[gas_free(gas_validate=gas_validate_function, gas_charge_post=gas_charge_post_function)]
+    public entry fun play(_ctx: &mut Context, _sender: &signer){
+    }
+}

moveos/moveos-stdlib/moveos-stdlib/doc/tx_result.md

@@ -8,6 +8,7 @@
 -  [Struct `TxResult`](#0x2_tx_result_TxResult)
 -  [Function `is_executed`](#0x2_tx_result_is_executed)
 -  [Function `gas_used`](#0x2_tx_result_gas_used)
+-  [Function `gas_payment_account`](#0x2_tx_result_gas_payment_account)
 
 
 <pre><code></code></pre>
@@ -45,6 +46,12 @@ We can get the result in the <code>post_execute</code> function.
 <dd>
  The gas used by the transaction.
 </dd>
+<dt>
+<code>gas_payment_account: <b>address</b></code>
+</dt>
+<dd>
+ The account for the gas payment.
+</dd>
 </dl>
 
 
@@ -96,4 +103,28 @@ We can get the result in the <code>post_execute</code> function.
 
 
 
+</details>
+
+<a name="0x2_tx_result_gas_payment_account"></a>
+
+## Function `gas_payment_account`
+
+
+
+<pre><code><b>public</b> <b>fun</b> <a href="tx_result.md#0x2_tx_result_gas_payment_account">gas_payment_account</a>(self: &<a href="tx_result.md#0x2_tx_result_TxResult">tx_result::TxResult</a>): <b>address</b>
+</code></pre>
+
+
+
+<details>
+<summary>Implementation</summary>
+
+
+<pre><code><b>public</b> <b>fun</b> <a href="tx_result.md#0x2_tx_result_gas_payment_account">gas_payment_account</a>(self: &<a href="tx_result.md#0x2_tx_result_TxResult">TxResult</a>): <b>address</b> {
+    self.gas_payment_account
+}
+</code></pre>
+
+
+
 </details>

moveos/moveos-stdlib/moveos-stdlib/sources/tx_result.move

@@ -11,6 +11,8 @@ module moveos_std::tx_result {
         executed: bool,
         /// The gas used by the transaction.
         gas_used: u64,
+        /// The account for the gas payment.
+        gas_payment_account: address,
     }
 
     public fun is_executed(self: &TxResult) : bool {
@@ -21,4 +23,8 @@ module moveos_std::tx_result {
         self.gas_used
     }
 
+    public fun gas_payment_account(self: &TxResult): address {
+        self.gas_payment_account
+    }
+
 }

moveos/moveos-types/src/moveos_std/tx_result.rs

@@ -16,6 +16,7 @@ pub const MODULE_NAME: &IdentStr = ident_str!("tx_result");
 pub struct TxResult {
     pub executed: bool,
     pub gas_used: u64,
+    pub gas_payment_account: AccountAddress,
 }
 
 impl MoveStructType for TxResult {
@@ -29,15 +30,17 @@ impl MoveStructState for TxResult {
         move_core_types::value::MoveStructLayout::new(vec![
             move_core_types::value::MoveTypeLayout::Bool,
             move_core_types::value::MoveTypeLayout::U64,
+            move_core_types::value::MoveTypeLayout::Address,
         ])
     }
 }
 
 impl TxResult {
-    pub fn new(status: &KeptVMStatus, gas_used: u64) -> Self {
+    pub fn new(status: &KeptVMStatus, gas_used: u64, gas_payment_account: AccountAddress) -> Self {
         Self {
             executed: matches!(status, KeptVMStatus::Executed),
             gas_used,
+            gas_payment_account,
         }
     }
 }