From 0a1700e239b926b32798cb918bf5ac6a25da2c19 Mon Sep 17 00:00:00 2001
From: Tanya S <120410716+stubbsta@users.noreply.github.com>
Date: Mon, 6 Jul 2026 17:49:20 +0200
Subject: [PATCH] replace RLN specific Result with generic Result (#4011)

---
 logos_delivery/waku/rln/nullifier_log.nim     |  4 +-
 logos_delivery/waku/rln/proof.nim             |  2 +-
 logos_delivery/waku/rln/protocol_types.nim    | 15 ++-----
 logos_delivery/waku/rln/rln.nim               |  4 +-
 logos_delivery/waku/rln/rln/rln_interface.nim | 12 +++---
 logos_delivery/waku/rln/rln/wrappers.nim      | 40 ++++++++++---------
 .../rln/waku_rln_relay_utils.nim              |  5 ++-
 tests/waku_rln_relay/utils_onchain.nim        |  2 +-
 8 files changed, 41 insertions(+), 43 deletions(-)

diff --git a/logos_delivery/waku/rln/nullifier_log.nim b/logos_delivery/waku/rln/nullifier_log.nim
index 372433c72..8a1a3cd6c 100644
--- a/logos_delivery/waku/rln/nullifier_log.nim
+++ b/logos_delivery/waku/rln/nullifier_log.nim
@@ -10,7 +10,7 @@ logScope:
 
 proc hasDuplicate*(
     rlnPeer: Rln, epoch: Epoch, proofMetadata: ProofMetadata
-): RlnResult[bool] =
+): Result[bool, string] =
   ## returns true if there is another message in the  `nullifierLog` of the `rlnPeer` with the same
   ## epoch and nullifier as `proofMetadata`'s epoch and nullifier
   ## otherwise, returns false
@@ -32,7 +32,7 @@ proc hasDuplicate*(
 
 proc updateLog*(
     rlnPeer: Rln, epoch: Epoch, proofMetadata: ProofMetadata
-): RlnResult[void] =
+): Result[void, string] =
   ## saves supplied proofMetadata `proofMetadata`
   ## in the `nullifierLog` of the `rlnPeer`
   ## Returns an error if it cannot update the log
diff --git a/logos_delivery/waku/rln/proof.nim b/logos_delivery/waku/rln/proof.nim
index 4a0c332c1..fbbe2292e 100644
--- a/logos_delivery/waku/rln/proof.nim
+++ b/logos_delivery/waku/rln/proof.nim
@@ -56,7 +56,7 @@ proc toRLNSignal*(wakumessage: WakuMessage): seq[byte] =
 
 proc generateRLNProof*(
     rln: Rln, input: seq[byte], senderEpochTime: float64
-): Future[RlnResult[seq[byte]]] {.async.} =
+): Future[Result[seq[byte], string]] {.async.} =
   let epoch = rln.calcEpoch(senderEpochTime)
   let nonce = rln.nonceManager.getNonce().valueOr:
     return err("could not get new message id to generate an rln proof: " & $error)
diff --git a/logos_delivery/waku/rln/protocol_types.nim b/logos_delivery/waku/rln/protocol_types.nim
index 29ee97083..66aa72f53 100644
--- a/logos_delivery/waku/rln/protocol_types.nim
+++ b/logos_delivery/waku/rln/protocol_types.nim
@@ -5,11 +5,8 @@ import ../waku_core, ../waku_keystore, ../common/protobuf
 
 export waku_keystore, waku_core
 
-type RlnResult*[T] = Result[T, string]
-
 ## RLN is a Nim wrapper for the data types used in zerokit RLN
 type RlnRaw* {.incompleteStruct.} = object
-type RlnInstanceResult* = RlnResult[ptr RlnRaw]
 
 type
   MerkleNode* = array[32, byte]
@@ -72,14 +69,10 @@ type ProofMetadata* = object
   shareY*: MerkleNode
   externalNullifier*: Nullifier
 
-type
-  MessageValidationResult* {.pure.} = enum
-    Valid
-    Invalid
-    Spam
-
-  MerkleNodeResult* = RlnResult[MerkleNode]
-  RateLimitProofResult* = RlnResult[RateLimitProof]
+type MessageValidationResult* {.pure.} = enum
+  Valid
+  Invalid
+  Spam
 
 # Protobufs enc and init
 proc init*(T: type RateLimitProof, buffer: seq[byte]): ProtoResult[T] =
diff --git a/logos_delivery/waku/rln/rln.nim b/logos_delivery/waku/rln/rln.nim
index dab5ec3ef..ec20cf0c8 100644
--- a/logos_delivery/waku/rln/rln.nim
+++ b/logos_delivery/waku/rln/rln.nim
@@ -183,7 +183,7 @@ proc monitorEpochs(rln: Rln) {.async.} =
 
 proc mount(
     conf: WakuRlnConfig, registrationHandler = none(RegistrationHandler)
-): Future[RlnResult[Rln]] {.async.} =
+): Future[Result[Rln, string]] {.async.} =
   var
     groupManager: GroupManager
     rln: Rln
@@ -258,7 +258,7 @@ proc isReady*(rlnPeer: Rln): Future[bool] {.async.} =
 
 proc new*(
     T: type Rln, conf: WakuRlnConfig, registrationHandler = none(RegistrationHandler)
-): Future[RlnResult[Rln]] {.async.} =
+): Future[Result[Rln, string]] {.async.} =
   ## Mounts the rln-relay protocol on the node.
   ## The rln-relay protocol can be mounted in two modes: on-chain and off-chain.
   ## Returns an error if the rln-relay protocol could not be mounted.
diff --git a/logos_delivery/waku/rln/rln/rln_interface.nim b/logos_delivery/waku/rln/rln/rln_interface.nim
index 60272ea3e..d9b2fc903 100644
--- a/logos_delivery/waku/rln/rln/rln_interface.nim
+++ b/logos_delivery/waku/rln/rln/rln_interface.nim
@@ -318,14 +318,14 @@ proc vecToSeq*(data: Vec_uint8): seq[byte] =
   if result.len > 0:
     copyMem(addr result[0], data.dataPtr, result.len)
 
-proc seqToFixed32*(data: openArray[byte]): RlnResult[array[32, byte]] =
+proc seqToFixed32*(data: openArray[byte]): Result[array[32, byte], string] =
   if data.len != FieldElementSize:
     return err("Expected 32 bytes, got " & $data.len)
   var output: array[32, byte]
   copyMem(addr output[0], unsafeAddr data[0], FieldElementSize)
   ok(output)
 
-proc cfrToBytesLe*(cfr: ptr CFr): RlnResult[array[32, byte]] =
+proc cfrToBytesLe*(cfr: ptr CFr): Result[array[32, byte], string] =
   let bytes = ffi_cfr_to_bytes_le(cfr)
   defer:
     ffi_vec_u8_free(bytes)
@@ -333,7 +333,7 @@ proc cfrToBytesLe*(cfr: ptr CFr): RlnResult[array[32, byte]] =
     return err("Invalid field byte length: " & $bytes.len)
   seqToFixed32(vecToSeq(bytes))
 
-proc bytesToCfrLe*(data: openArray[byte]): RlnResult[ptr CFr] =
+proc bytesToCfrLe*(data: openArray[byte]): Result[ptr CFr, string] =
   ## Allocate a ptr CFr from raw bytes. Caller MUST ffi_cfr_free(x).
   var vec = toVecUint8(data)
   let res = ffi_bytes_le_to_cfr(addr vec)
@@ -343,7 +343,7 @@ proc bytesToCfrLe*(data: openArray[byte]): RlnResult[ptr CFr] =
 
 proc cfrResultToBytes*(
     res: CResultCFrPtrVecU8, prefix: string
-): RlnResult[array[32, byte]] =
+): Result[array[32, byte], string] =
   ## Consume a CResultCFrPtrVecU8: read bytes if ok, free the CFr, or
   ## propagate the error (also freeing the error string).
   if res.ok.isNil:
@@ -352,7 +352,7 @@ proc cfrResultToBytes*(
     ffi_cfr_free(res.ok)
   cfrToBytesLe(res.ok)
 
-proc hashToFieldLe*(data: openArray[byte]): RlnResult[ptr CFr] =
+proc hashToFieldLe*(data: openArray[byte]): Result[ptr CFr, string] =
   ## Caller MUST ffi_cfr_free the returned ptr.
   var vec = toVecUint8(data)
   let cfr = ffi_hash_to_field_le(addr vec)
@@ -360,7 +360,7 @@ proc hashToFieldLe*(data: openArray[byte]): RlnResult[ptr CFr] =
     return err("Failed to hash to field")
   ok(cfr)
 
-proc poseidonPairLe*(a, b: openArray[byte]): RlnResult[array[32, byte]] =
+proc poseidonPairLe*(a, b: openArray[byte]): Result[array[32, byte], string] =
   ## Poseidon hash of exactly two 32-byte field elements (little-endian).
   ## zerokit v2 FFI only exposes pair-input Poseidon; unary is not supported.
   let aPtr = bytesToCfrLe(a).valueOr:
diff --git a/logos_delivery/waku/rln/rln/wrappers.nim b/logos_delivery/waku/rln/rln/wrappers.nim
index 5a39aedf0..4f46fc164 100644
--- a/logos_delivery/waku/rln/rln/wrappers.nim
+++ b/logos_delivery/waku/rln/rln/wrappers.nim
@@ -12,9 +12,9 @@ logScope:
 # Forward decl; body defined below.
 proc generateExternalNullifier*(
   epoch: Epoch, rlnIdentifier: RlnIdentifier
-): RlnResult[ExternalNullifier]
+): Result[ExternalNullifier, string]
 
-proc toRootVec(validRoots: seq[MerkleNode]): RlnResult[Vec_CFr] =
+proc toRootVec(validRoots: seq[MerkleNode]): Result[Vec_CFr, string] =
   ## Caller MUST ffi_vec_cfr_free the returned Vec_CFr.
   var roots = ffi_vec_cfr_new(csize_t(validRoots.len))
   for root in validRoots:
@@ -27,7 +27,7 @@ proc toRootVec(validRoots: seq[MerkleNode]): RlnResult[Vec_CFr] =
 
 proc proofPtrToRateLimitProof(
     proofPtr: ptr FFI_RLNProof, epoch: Epoch, rlnIdentifier: RlnIdentifier
-): RlnResult[RateLimitProof] =
+): Result[RateLimitProof, string] =
   var proofHandle = proofPtr
   let proofBytesRes = ffi_rln_proof_to_bytes_le(addr proofHandle)
   if hasError(proofBytesRes.err):
@@ -93,7 +93,7 @@ proc proofPtrToRateLimitProof(
 
   ok(output)
 
-proc parseCredentialVec(vec: var Vec_CFr): RlnResult[IdentityCredential] =
+proc parseCredentialVec(vec: var Vec_CFr): Result[IdentityCredential, string] =
   ## Vec_CFr order: idTrapdoor, idNullifier, idSecretHash, idCommitment.
   if int(ffi_vec_cfr_len(addr vec)) != 4:
     return err("Unexpected credential element count")
@@ -120,13 +120,13 @@ proc parseCredentialVec(vec: var Vec_CFr): RlnResult[IdentityCredential] =
     )
   )
 
-proc membershipKeyGen*(): RlnResult[IdentityCredential] =
+proc membershipKeyGen*(): Result[IdentityCredential, string] =
   var vec = ffi_extended_key_gen()
   defer:
     ffi_vec_cfr_free(vec)
   parseCredentialVec(vec)
 
-proc createRLNInstanceLocal(): RlnInstanceResult =
+proc createRLNInstanceLocal(): Result[ptr RlnRaw, string] =
   ## Creates a stateless RLN instance (no local Merkle tree).
   let res = ffi_rln_new()
   if res.ok.isNil():
@@ -135,18 +135,18 @@ proc createRLNInstanceLocal(): RlnInstanceResult =
     return err(msg)
   ok(res.ok)
 
-proc createRLNInstance*(): RlnInstanceResult =
+proc createRLNInstance*(): Result[ptr RlnRaw, string] =
   ## Wraps createRLNInstanceLocal with metrics timing.
-  var res: RlnInstanceResult
+  var res: Result[ptr RlnRaw, string]
   waku_rln_instance_creation_duration_seconds.nanosecondTime:
     res = createRLNInstanceLocal()
   return res
 
-proc poseidon*(left, right: seq[byte]): RlnResult[array[32, byte]] =
+proc poseidon*(left, right: seq[byte]): Result[array[32, byte], string] =
   ## Poseidon hash of exactly 2 inputs; zerokit v2 FFI only exposes the pair variant.
   poseidonPairLe(left, right)
 
-proc toLeaf*(rateCommitment: RateCommitment): RlnResult[seq[byte]] =
+proc toLeaf*(rateCommitment: RateCommitment): Result[seq[byte], string] =
   let idCommitment = rateCommitment.idCommitment
   var userMessageLimit: array[32, byte]
   try:
@@ -164,7 +164,7 @@ proc toLeaf*(rateCommitment: RateCommitment): RlnResult[seq[byte]] =
     retLeaf[i] = leaf[i]
   return ok(retLeaf)
 
-proc toLeaves*(rateCommitments: seq[RateCommitment]): RlnResult[seq[seq[byte]]] =
+proc toLeaves*(rateCommitments: seq[RateCommitment]): Result[seq[seq[byte]], string] =
   var leaves = newSeq[seq[byte]]()
   for rateCommitment in rateCommitments:
     let leaf = toLeaf(rateCommitment).valueOr:
@@ -174,7 +174,7 @@ proc toLeaves*(rateCommitments: seq[RateCommitment]): RlnResult[seq[seq[byte]]]
 
 proc generateExternalNullifier*(
     epoch: Epoch, rlnIdentifier: RlnIdentifier
-): RlnResult[ExternalNullifier] =
+): Result[ExternalNullifier, string] =
   ## externalNullifier = Poseidon(H(epoch), H(rlnIdentifier)); H = ffi_hash_to_field_le.
   let epochFr = hashToFieldLe(@epoch).valueOr:
     return err("Failed to hash epoch to field: " & error)
@@ -194,7 +194,7 @@ proc generateExternalNullifier*(
       "Failed to serialize external nullifier: " & e
   )
 
-proc extractMetadata*(proof: RateLimitProof): RlnResult[ProofMetadata] =
+proc extractMetadata*(proof: RateLimitProof): Result[ProofMetadata, string] =
   let externalNullifier = generateExternalNullifier(proof.epoch, proof.rlnIdentifier).valueOr:
     return err("Failed to compute external nullifier: " & error)
   return ok(
@@ -206,7 +206,9 @@ proc extractMetadata*(proof: RateLimitProof): RlnResult[ProofMetadata] =
     )
   )
 
-proc buildPathElementsVec(pathElements: seq[byte], depth: int): RlnResult[Vec_CFr] =
+proc buildPathElementsVec(
+    pathElements: seq[byte], depth: int
+): Result[Vec_CFr, string] =
   ## Caller MUST ffi_vec_cfr_free the returned Vec_CFr.
   var vec = ffi_vec_cfr_new(csize_t(depth))
   for i in 0 ..< depth:
@@ -222,7 +224,9 @@ proc buildPathElementsVec(pathElements: seq[byte], depth: int): RlnResult[Vec_CF
     ffi_cfr_free(element)
   ok(vec)
 
-proc buildWitnessInput(witness: RLNWitnessInput): RlnResult[ptr FFI_RLNWitnessInput] =
+proc buildWitnessInput(
+    witness: RLNWitnessInput
+): Result[ptr FFI_RLNWitnessInput, string] =
   ## ffi_rln_witness_input_new copies all inputs, so the intermediate CFrs/vecs
   ## are freed here. Caller MUST ffi_rln_witness_input_free the returned handle.
   let depth = witness.identity_path_index.len
@@ -287,7 +291,7 @@ proc generateRlnProofWithWitness*(
     witness: RLNWitnessInput,
     epoch: Epoch,
     rlnIdentifier: RlnIdentifier,
-): RlnResult[RateLimitProof] =
+): Result[RateLimitProof, string] =
   let witnessHandle = buildWitnessInput(witness).valueOr:
     return
       err("failed call to buildWitnessInput in generateRlnProofWithWitness: " & error)
@@ -306,7 +310,7 @@ proc generateRlnProofWithWitness*(
 
 proc buildRlnProof(
     proof: RateLimitProof, externalNullifier: ExternalNullifier
-): RlnResult[ptr FFI_RLNProof] =
+): Result[ptr FFI_RLNProof, string] =
   ## ffi_rln_proof_new copies all inputs, so the intermediate CFrs are freed
   ## here. Caller MUST ffi_rln_proof_free the returned handle.
   var groth16Vec = toVecUint8(proof.proof)
@@ -345,7 +349,7 @@ proc verifyRlnProof*(
     proof: RateLimitProof,
     signal: openArray[byte],
     validRoots: seq[MerkleNode],
-): RlnResult[bool] =
+): Result[bool, string] =
   if validRoots.len == 0:
     return err("verifyRlnProof requires at least one valid root (stateless mode)")
 
diff --git a/tests/waku_rln_relay/rln/waku_rln_relay_utils.nim b/tests/waku_rln_relay/rln/waku_rln_relay_utils.nim
index 15647a5ef..d7577b88a 100644
--- a/tests/waku_rln_relay/rln/waku_rln_relay_utils.nim
+++ b/tests/waku_rln_relay/rln/waku_rln_relay_utils.nim
@@ -1,5 +1,6 @@
 import std/options
 import std/tempfiles
+import results
 
 import
   logos_delivery/waku/rln,
@@ -8,12 +9,12 @@ import
     protocol_metrics, nonce_manager,
   ]
 
-proc createRLNInstanceWrapper*(): RlnInstanceResult =
+proc createRLNInstanceWrapper*(): Result[ptr RlnRaw, string] =
   return createRlnInstance()
 
 proc unsafeAppendRLNProof*(
     rlnPeer: Rln, msg: var WakuMessage, epoch: Epoch, messageId: MessageId
-): RlnResult[void] =
+): Result[void, string] =
   ## Test helper derived from the publish-path proof flow.
   ## - Skips nonce validation to intentionally allow generating "bad" message IDs for tests.
   ## - Forces a real-time on-chain Merkle root refresh via `updateRoots()` and fetches Merkle
diff --git a/tests/waku_rln_relay/utils_onchain.nim b/tests/waku_rln_relay/utils_onchain.nim
index 422b8c351..4955d8d64 100644
--- a/tests/waku_rln_relay/utils_onchain.nim
+++ b/tests/waku_rln_relay/utils_onchain.nim
@@ -37,7 +37,7 @@ proc generateCredentials*(): IdentityCredential =
 
 proc getRateCommitment*(
     idCredential: IdentityCredential, userMessageLimit: UserMessageLimit
-): RlnResult[RawRateCommitment] =
+): Result[RawRateCommitment, string] =
   return RateCommitment(
     idCommitment: idCredential.idCommitment, userMessageLimit: userMessageLimit
   ).toLeaf()