Add a separate error for nonexistent contract input

CHANGELOG.md

@@ -17,6 +17,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 ### Breaking 
 - [863](https://github.com/FuelLabs/fuel-vm/pull/863): Changed StorageRead::read to load a serialized value starting from a offset. The function returns an optional value equal to the number of bytes read when defined, or none if the offset specified in input is outside the boundaries of the serialized value read.
+- [868](https://github.com/FuelLabs/fuel-vm/pull/868): Fixed error message when having a nonexistent contract in inputs. Instead of saying "contract was in inputs, but doesn't exist", the message was just "contract not in inputs". Now there's a separate error for that.
 
 ## [Version 0.58.2]
 

fuel-asm/src/panic_reason.rs

@@ -158,7 +158,8 @@ enum_from! {
         UnsupportedOperationType = 0x3a,
         /// Read alt_bn_128 curve point is invalid.
         InvalidEllipticCurvePoint = 0x3b,
-
+        /// Given input contract does not exist.
+        InputContractDoesNotExist = 0x3c,
     }
 }
 

fuel-vm/src/interpreter/executors/main.rs

@@ -96,6 +96,7 @@ use fuel_tx::{
     Input,
     Receipt,
     ScriptExecutionResult,
+    Transaction,
     Upgrade,
     UpgradeMetadata,
     UpgradePurpose,
@@ -845,12 +846,59 @@ where
     }
 
     pub(crate) fn run(&mut self) -> Result<ProgramState, InterpreterError<S::DataError>> {
+        for input in self.transaction().inputs() {
+            if let Input::Contract(contract) = input {
+                if !self.check_contract_exists(&contract.contract_id)? {
+                    return Err(InterpreterError::Panic(
+                        PanicReason::InputContractDoesNotExist,
+                    ));
+                }
+            }
+        }
+
         // TODO: Remove `Create`, `Upgrade`, and `Upload` from here
         //  https://github.com/FuelLabs/fuel-vm/issues/251
         let gas_costs = self.gas_costs().clone();
         let fee_params = *self.fee_params();
         let base_asset_id = *self.base_asset_id();
         let gas_price = self.gas_price();
+
+        #[cfg(debug_assertions)]
+        // The `match` statement exists to ensure that all variants of `Transaction`
+        // are handled below. If a new variant is added, the compiler will
+        // emit an error.
+        {
+            let mint: Transaction = Transaction::mint(
+                Default::default(),
+                Default::default(),
+                Default::default(),
+                Default::default(),
+                Default::default(),
+                Default::default(),
+            )
+            .into();
+            match mint {
+                Transaction::Create(_) => {
+                    // Handled in the `self.tx.as_create_mut()` branch.
+                }
+                Transaction::Upgrade(_) => {
+                    // Handled in the `self.tx.as_upgrade_mut()` branch.
+                }
+                Transaction::Upload(_) => {
+                    // Handled in the `self.tx.as_upload_mut()` branch.
+                }
+                Transaction::Blob(_) => {
+                    // Handled in the `self.tx.as_blob_mut()` branch.
+                }
+                Transaction::Script(_) => {
+                    // Handled in the `else` branch.
+                }
+                Transaction::Mint(_) => {
+                    // The `Mint` transaction doesn't implement `ExecutableTransaction`.
+                }
+            };
+        }
+
         let state = if let Some(create) = self.tx.as_create_mut() {
             Self::deploy_inner(
                 create,
@@ -896,25 +944,15 @@ where
             )?;
             ProgramState::Return(1)
         } else {
-            if self.transaction().inputs().iter().any(|input| {
-                if let Input::Contract(contract) = input {
-                    !self
-                        .check_contract_exists(&contract.contract_id)
-                        .unwrap_or(false)
-                } else {
-                    false
-                }
-            }) {
-                return Err(InterpreterError::Panic(PanicReason::ContractNotInInputs));
-            }
-
             let gas_limit;
             let is_empty_script;
             if let Some(script) = self.transaction().as_script() {
                 gas_limit = *script.script_gas_limit();
                 is_empty_script = script.script().is_empty();
             } else {
-                unreachable!("Only `Create` and `Script` transactions can be executed inside of the VM")
+                unreachable!(
+                    "Only `Script` transactions can be executed inside of the VM"
+                )
             }
 
             // TODO set tree balance