From ac0436b1de1c016f5e3efd598924c6eb7018594e Mon Sep 17 00:00:00 2001
From: Thibault Martinez <thibault@iota.org>
Date: Tue, 5 Apr 2022 12:46:50 +0200
Subject: [PATCH] Simplify SDRUC syntactic validation rules

---
 bee-message/src/error.rs      |  8 --------
 bee-message/src/output/mod.rs | 13 ++-----------
 2 files changed, 2 insertions(+), 19 deletions(-)

diff --git a/bee-message/src/error.rs b/bee-message/src/error.rs
index 11af00cb70..0f3a40e424 100644
--- a/bee-message/src/error.rs
+++ b/bee-message/src/error.rs
@@ -45,7 +45,6 @@ pub enum Error {
     InsufficientStorageDepositAmount { amount: u64, required: u64 },
     StorageDepositReturnExceedsOutputAmount { deposit: u64, amount: u64 },
     InsufficientStorageDepositReturnAmount { deposit: u64, required: u64 },
-    UnnecessaryStorageDepositReturnCondition { logical_amount: u64, required: u64 },
     InvalidEssenceKind(u8),
     InvalidFeatureBlockCount(<FeatureBlockCount as TryFrom<usize>>::Error),
     InvalidFeatureBlockKind(u8),
@@ -170,13 +169,6 @@ impl fmt::Display for Error {
                 f,
                 "storage deposit return of {deposit} exceeds the original output amount of {amount}"
             ),
-            Error::UnnecessaryStorageDepositReturnCondition {
-                logical_amount,
-                required,
-            } => write!(
-                f,
-                "no storage deposit return is needed, the logical output amount {logical_amount} already covers the required deposit {required}"
-            ),
             Error::InvalidEssenceKind(k) => write!(f, "invalid essence kind: {}", k),
             Error::InvalidFeatureBlockCount(count) => write!(f, "invalid feature block count: {}", count),
             Error::InvalidFeatureBlockKind(k) => write!(f, "invalid feature block kind: {}", k),
diff --git a/bee-message/src/output/mod.rs b/bee-message/src/output/mod.rs
index a958724135..460c660b8e 100644
--- a/bee-message/src/output/mod.rs
+++ b/bee-message/src/output/mod.rs
@@ -234,7 +234,7 @@ impl Output {
             .and_then(UnlockConditions::storage_deposit_return)
         {
             // We can't return more tokens than were originally contained in the output.
-            // `0` ≤ `Amount` - `Return Amount`
+            // `Return Amount` ≤ `Amount`.
             if return_condition.amount() > self.amount() {
                 return Err(Error::StorageDepositReturnExceedsOutputAmount {
                     deposit: return_condition.amount(),
@@ -244,22 +244,13 @@ impl Output {
 
             let minimum_deposit = minimum_storage_deposit(config, return_condition.return_address());
 
-            // `Return Amount` must be ≥ than `Minimum Storage Deposit`
+            // `Minimum Storage Deposit` ≤  `Return Amount`
             if return_condition.amount() < minimum_deposit {
                 return Err(Error::InsufficientStorageDepositReturnAmount {
                     deposit: return_condition.amount(),
                     required: minimum_deposit,
                 });
             }
-
-            // Check if the storage deposit return was required in the first place.
-            // `Amount` - `Return Amount` ≤ `Required Storage Deposit of the Output`
-            if self.amount() - return_condition.amount() > required_output_amount {
-                return Err(Error::UnnecessaryStorageDepositReturnCondition {
-                    logical_amount: self.amount() - return_condition.amount(),
-                    required: required_output_amount,
-                });
-            }
         }
 
         Ok(())