From 295e70232f2db6b5f0c2f0ac2aaddc1fbf511758 Mon Sep 17 00:00:00 2001
From: Quantum Explorer <quantum@dash.org>
Date: Thu, 11 Dec 2025 06:56:44 +0700
Subject: [PATCH] fix(dpp): Return UnsupportedFeatureError for legacy state
 transition structure validation

---
 packages/rs-dpp/src/state_transition/mod.rs   | 44 ++++++++-----------
 .../src/platform/transition/validation.rs     | 26 ++++++++++-
 2 files changed, 43 insertions(+), 27 deletions(-)

diff --git a/packages/rs-dpp/src/state_transition/mod.rs b/packages/rs-dpp/src/state_transition/mod.rs
index bf918fa950..4f14f59ba2 100644
--- a/packages/rs-dpp/src/state_transition/mod.rs
+++ b/packages/rs-dpp/src/state_transition/mod.rs
@@ -44,6 +44,8 @@ mod traits;
 
 // pub mod state_transition_fee;
 
+#[cfg(feature = "state-transition-validation")]
+use crate::consensus::basic::UnsupportedFeatureError;
 #[cfg(feature = "state-transition-signing")]
 use crate::consensus::signature::InvalidSignaturePublicKeySecurityLevelError;
 #[cfg(feature = "state-transition-validation")]
@@ -1167,32 +1169,22 @@ impl StateTransitionStructureValidation for StateTransition {
         platform_version: &PlatformVersion,
     ) -> crate::validation::SimpleConsensusValidationResult {
         match self {
-            StateTransition::DataContractCreate(_) => {
-                crate::validation::SimpleConsensusValidationResult::default()
-            }
-            StateTransition::DataContractUpdate(_) => {
-                crate::validation::SimpleConsensusValidationResult::default()
-            }
-            StateTransition::Batch(_) => {
-                crate::validation::SimpleConsensusValidationResult::default()
-            }
-            StateTransition::IdentityCreate(_) => {
-                crate::validation::SimpleConsensusValidationResult::default()
-            }
-            StateTransition::IdentityTopUp(_) => {
-                crate::validation::SimpleConsensusValidationResult::default()
-            }
-            StateTransition::IdentityCreditWithdrawal(_) => {
-                crate::validation::SimpleConsensusValidationResult::default()
-            }
-            StateTransition::IdentityUpdate(_) => {
-                crate::validation::SimpleConsensusValidationResult::default()
-            }
-            StateTransition::IdentityCreditTransfer(_) => {
-                crate::validation::SimpleConsensusValidationResult::default()
-            }
-            StateTransition::MasternodeVote(_) => {
-                crate::validation::SimpleConsensusValidationResult::default()
+            StateTransition::DataContractCreate(_)
+            | StateTransition::DataContractUpdate(_)
+            | StateTransition::Batch(_)
+            | StateTransition::IdentityCreate(_)
+            | StateTransition::IdentityTopUp(_)
+            | StateTransition::IdentityCreditWithdrawal(_)
+            | StateTransition::IdentityUpdate(_)
+            | StateTransition::IdentityCreditTransfer(_)
+            | StateTransition::MasternodeVote(_) => {
+                crate::validation::SimpleConsensusValidationResult::new_with_error(
+                    UnsupportedFeatureError::new(
+                        "structure validation for identity-based state transitions".to_string(),
+                        platform_version.protocol_version,
+                    )
+                    .into(),
+                )
             }
             StateTransition::IdentityCreditTransferToAddresses(transition) => {
                 transition.validate_structure(platform_version)
diff --git a/packages/rs-sdk/src/platform/transition/validation.rs b/packages/rs-sdk/src/platform/transition/validation.rs
index c876a5649f..846d9ddae2 100644
--- a/packages/rs-sdk/src/platform/transition/validation.rs
+++ b/packages/rs-sdk/src/platform/transition/validation.rs
@@ -1,10 +1,24 @@
 use crate::Error;
 use dpp::{
+    consensus::{basic::BasicError, ConsensusError},
     state_transition::{StateTransition, StateTransitionStructureValidation},
     version::PlatformVersion,
 };
 
+/// Checks if an error is an UnsupportedFeatureError
+fn is_unsupported_feature_error(error: &ConsensusError) -> bool {
+    matches!(
+        error,
+        ConsensusError::BasicError(BasicError::UnsupportedFeatureError(_))
+    )
+}
+
 /// Ensures a state transition passes structure validation before broadcasting.
+///
+/// Note: UnsupportedFeatureError is allowed to pass through, as it indicates
+/// that structure validation is not implemented for that state transition type
+/// (e.g., identity-based state transitions). The platform will still perform
+/// validation during execution.
 pub(crate) fn ensure_valid_state_transition_structure(
     state_transition: &StateTransition,
     platform_version: &PlatformVersion,
@@ -13,6 +27,16 @@ pub(crate) fn ensure_valid_state_transition_structure(
     if validation_result.is_valid() {
         Ok(())
     } else {
-        Err(validation_result.into())
+        // Allow UnsupportedFeatureError to pass through - this means structure
+        // validation is not implemented for this state transition type
+        let all_unsupported_feature_errors = validation_result
+            .errors
+            .iter()
+            .all(is_unsupported_feature_error);
+        if all_unsupported_feature_errors {
+            Ok(())
+        } else {
+            Err(validation_result.into())
+        }
     }
 }