feat(wasm-sdk): add shielded pool WASM bindings and query methods

[QuantumExplorer]

Issue being fixed or feature implemented

Adds the WASM/JS layer for shielded pool functionality in wasm-dpp2 and wasm-sdk.

What was done?

wasm-dpp2: Shielded state transition wrappers

• ShieldTransitionWasm — shield (deposit) with inputs, actions, amount, proof, binding signature
• ShieldFromAssetLockTransitionWasm — shield from asset lock with proof verification
• ShieldedTransferTransitionWasm — private transfer between shielded addresses
• UnshieldTransitionWasm — withdraw from shielded pool to transparent address
• ShieldedWithdrawalTransitionWasm — withdraw from shielded pool to core chain
• computePlatformSighash utility function exposed to JS
• All wrappers include toBytes/fromBytes/toJSON/toObject/toStateTransition/getModifiedDataIds
• Replaced todo!() panics in StateTransitionWasm for shielded variants with proper handling

wasm-sdk: Shielded pool query methods

• getShieldedPoolState — total shielded pool balance (BigInt)
• getShieldedEncryptedNotes(startIndex, count) — paginated encrypted notes
• getShieldedAnchors — valid anchors for Orchard spend proofs
• getMostRecentShieldedAnchor — latest 32-byte anchor
• getShieldedNullifiers(nullifiers) — check nullifier spent/unspent status
• All 5 queries have WithProofInfo variants returning ProofMetadataResponse<T>
• ShieldedEncryptedNoteWasm and ShieldedNullifierStatusWasm wrapper types with TypeScript interfaces

How Has This Been Tested?

• cargo check -p wasm-dpp2 ✅
• cargo check -p wasm-sdk ✅
• cargo clippy -p wasm-dpp2 ✅ (no warnings)
• cargo clippy -p wasm-sdk ✅ (no warnings)
• cargo fmt ✅

Breaking Changes

None. All additions are new public API.

Checklist

• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have added or updated relevant unit/integration/functional tests
• I have made corresponding changes to the documentation
• I have added the PR to a milestone (if applicable)

🤖 Generated with Claude Code

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ℹ️ Review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro

Run ID: 54aa90cd-a74a-4513-a54c-93a94913330a

📥 Commits

Reviewing files that changed from the base of the PR and between c5325c9 and 98a20b6.

📒 Files selected for processing (5)

• packages/wasm-dpp2/src/shielded/mod.rs
• packages/wasm-dpp2/src/state_transitions/proof_result.rs
• packages/wasm-sdk/src/lib.rs
• packages/wasm-sdk/src/queries/mod.rs
• packages/wasm-sdk/src/queries/shielded.rs

📝 Walkthrough

Walkthrough

This PR introduces comprehensive shielded state transition support to the Dash SDK by adding five new shielded methods (shield, shieldedTransfer, unshield, shieldFromAssetLock, shieldedWithdrawal) to the Platform class and implementing WebAssembly bindings for the corresponding transition types.

Changes

Cohort / File(s)	Summary
Platform Shielded Namespace packages/js-dash-sdk/src/SDK/Client/Platform/Platform.ts	Added new Shielded interface and shielded member on Platform, grouping five shield-related methods under a single namespace with bound implementations.
Shielded Method Implementations packages/js-dash-sdk/src/SDK/Client/Platform/methods/shielded/shield.ts, shieldedTransfer.ts, unshield.ts, shieldFromAssetLock.ts, shieldedWithdrawal.ts	Five new async methods that serialize, initialize platform, construct state transitions via DPP, and broadcast with skipValidation enabled. Each follows an identical pattern with debug/silly logging.
WASM DPP Enum Support packages/wasm-dpp/src/identity/state_transition/transition_types.rs, state_transition/state_transition_factory.rs	Added five new enum variants (Shield, ShieldedTransfer, Unshield, ShieldFromAssetLock, ShieldedWithdrawal) to StateTransitionTypeWasm and replaced placeholder todos with concrete mappings in state transition factory.
WASM DPP2 Module Surface packages/wasm-dpp2/src/lib.rs, shielded/mod.rs	Added public shielded module with exports for five Wasm transition types and a new compute_platform_sighash_wasm function with input validation for bundle_commitment length.
WASM Shielded Transition Wrappers packages/wasm-dpp2/src/shielded/shield_transition.rs, shielded_transfer_transition.rs, unshield_transition.rs, shieldFromAssetLockTransition.rs, shieldedWithdrawalTransition.rs	Five new Wasm wrapper types (ShieldTransitionWasm, ShieldedTransferTransitionWasm, UnshieldTransitionWasm, ShieldFromAssetLockTransitionWasm, ShieldedWithdrawalTransitionWasm) exposing comprehensive getters, serialization helpers (to/from bytes, JSON, object), and state transition conversions via wasm_bindgen.
State Transition Error Handling packages/wasm-dpp2/src/state_transitions/base/state_transition.rs	Converted placeholder panic-like todos for shielded withdrawal to None returns in getters; added invalid_argument error returns for set operations (setOwnerId, setIdentityContractNonce, setIdentityNonce) on shielded transitions.

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~20 minutes

Poem

🐰 Five shielded transitions bloom,
WASM wrappers light the room,
Platform methods cast their charm,
Broadcasting transitions warm,
Privacy and safety arm in arm!

🚥 Pre-merge checks | ✅ 3

✅ Passed checks (3 passed)

Check name	Status	Explanation
Docstring Coverage	✅ Passed	Docstring coverage is 100.00% which is sufficient. The required threshold is 80.00%.
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The PR title accurately describes the main addition: shielded pool WASM bindings and query/broadcast methods across wasm-dpp2, wasm-dpp, and js-dash-sdk packages.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Post copyable unit tests in a comment
• Commit unit tests in branch feat/zk-wasm-js-bindings

📝 Coding Plan

• Generate coding plan for human review comments

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Actionable comments posted: 4

🧹 Nitpick comments (3)

packages/wasm-dpp2/src/shielded/mod.rs (1)

28-33: Consider consistent validation style.

The length validation and conversion on lines 28-34 is correct, but expect("checked length above") could be replaced with unwrap() for consistency, since the length is already validated. This is a minor style preference.

♻️ Optional: use unwrap() after validation

     if bundle_commitment.len() != 32 {
         return Err(crate::error::WasmDppError::invalid_argument(&format!(
             "bundleCommitment must be exactly 32 bytes, got {}",
             bundle_commitment.len()
         )));
     }
-    let commitment: &[u8; 32] = bundle_commitment.try_into().expect("checked length above");
+    let commitment: &[u8; 32] = bundle_commitment.try_into().unwrap();

🤖 Prompt for AI Agents

Verify each finding against the current code and only fix it if needed.

In `@packages/wasm-dpp2/src/shielded/mod.rs` around lines 28 - 33, Replace the
post-validation call that uses expect("checked length above") with unwrap() for
stylistic consistency: after you validate bundle_commitment.len() != 32 and
return an error, use unwrap() when converting/creating the fixed-size array (the
same spot currently calling expect) so the code relies on the prior check and
matches the project's validation style (refer to the bundle_commitment length
check and the conversion site where expect("checked length above") is used).

packages/wasm-dpp2/src/shielded/shielded_transfer_transition.rs (1)

88-116: Add a round-trip test for this wasm-facing ABI.

toBytes/fromBytes plus the JS-visible getters are new public surface, and this PR explicitly ships without test updates. A small round-trip/golden test here would catch wire-format drift and wrong-variant regressions before they reach the SDK.

🤖 Prompt for AI Agents

Verify each finding against the current code and only fix it if needed.

In `@packages/wasm-dpp2/src/shielded/shielded_transfer_transition.rs` around lines
88 - 116, Add a round-trip unit test exercising the wasm ABI: construct a
ShieldedTransferTransitionWasm instance, call to_bytes(), pass the bytes into
from_bytes() and assert the resulting ShieldedTransferTransitionWasm equals the
original; also include a JSON round-trip by calling to_json() and verifying the
serialized value round-trips (or matches expected golden JSON), and verify
to_state_transition() produces the expected StateTransition variant. Target the
wasm-facing symbols to_bytes, from_bytes, to_json, to_state_transition and
assert equality of the core inner StateTransition::ShieldedTransfer data to
catch wire-format or variant regressions.

packages/js-dash-sdk/src/SDK/Client/Platform/Platform.ts (1)

202-208: Consider a shared helper for the shielded broadcast path.

These five bindings fan out to near-identical modules today. Once you add the missing decoded-type guard or any future validation/logging tweak, you'll need to keep five copies in sync. A small helper that takes { expectedType, logPrefix } would make this surface much harder to drift.

🤖 Prompt for AI Agents

Verify each finding against the current code and only fix it if needed.

In `@packages/js-dash-sdk/src/SDK/Client/Platform/Platform.ts` around lines 202 -
208, The five near-identical bindings under this.shielded (shield,
shieldedTransfer, unshield, shieldFromAssetLock, shieldedWithdrawal) duplicate
broadcast/validation logic; extract a small helper (e.g.,
createShieldedBinder(expectedType, logPrefix)) that returns a bound function
given a method reference and metadata, then replace the direct .bind(this) calls
with calls to that helper (pass the original method function like shieldMethod,
shieldedTransferMethod, unshieldMethod, shieldFromAssetLockMethod,
shieldedWithdrawalMethod and the appropriate expectedType/logPrefix) so shared
decoded-type guards, validation and logging live in one place.

🤖 Prompt for all review comments with AI agents

Verify each finding against the current code and only fix it if needed.

Inline comments:
In `@packages/js-dash-sdk/src/SDK/Client/Platform/methods/shielded/shield.ts`:
- Around line 24-31: After deserializing the transition with
dpp.stateTransition.createFromBuffer in shield(), add a type guard that checks
transition.getType() and ensure it matches the expected StateTransition type for
shield (e.g., ShieldedTransfer/Shield/ShieldFromAssetLock/ShieldedWithdrawal as
appropriate) before calling broadcastStateTransition(this, await transition,
...); if the type does not match, throw or return a clear error. Apply the same
guard/check (use .getType() on the result of
dpp.stateTransition.createFromBuffer) to all other shielded entrypoints so each
only accepts its intended StateTransition variant prior to calling
broadcastStateTransition.

In `@packages/js-dash-sdk/src/SDK/Client/Platform/Platform.ts`:
- Around line 37-41: The three new shielded module filenames use mixed/camel
casing; rename the files shieldFromAssetLock.ts, shieldedTransfer.ts, and
shieldedWithdrawal.ts to kebab-case (shield-from-asset-lock.ts,
shielded-transfer.ts, shielded-withdrawal.ts) and update all imports/exports
referencing them (e.g., the imports in Platform.ts: shieldFromAssetLockMethod,
shieldedTransferMethod, shieldedWithdrawalMethod) to use the new kebab-case
paths; also update any barrel/index exports and tests or references across the
repo to the new filenames so imports remain consistent.

In `@packages/wasm-dpp/src/state_transition/state_transition_factory.rs`:
- Around line 82-96: The Shield-related state transition variants
(StateTransition::Shield, ::ShieldedTransfer, ::Unshield, ::ShieldFromAssetLock,
::ShieldedWithdrawal) call serde_wasm_bindgen::to_value(&st) but fail to compile
because the Serialize impls are behind the rs-dpp "serde-conversion" feature;
fix this by enabling that feature for the dpp dependency in wasm-dpp's
Cargo.toml (add "serde-conversion" to the features list for dpp) so those types
derive Serialize and serde_wasm_bindgen::to_value(&st) will compile.

In `@packages/wasm-dpp2/src/shielded/mod.rs`:
- Around line 16-36: The doc comment for compute_platform_sighash_wasm
incorrectly states that extraData includes an amount for unshield and shielded
withdrawal transitions; update the comment to match the rs-dpp implementation by
removing references to amount and describing extraData as just the output
address bytes for unshield transitions and the output script bytes for shielded
withdrawal transitions (see the extra_sighash_data construction in unshield.rs
and shielded_withdrawal.rs for reference).

---

Nitpick comments:
In `@packages/js-dash-sdk/src/SDK/Client/Platform/Platform.ts`:
- Around line 202-208: The five near-identical bindings under this.shielded
(shield, shieldedTransfer, unshield, shieldFromAssetLock, shieldedWithdrawal)
duplicate broadcast/validation logic; extract a small helper (e.g.,
createShieldedBinder(expectedType, logPrefix)) that returns a bound function
given a method reference and metadata, then replace the direct .bind(this) calls
with calls to that helper (pass the original method function like shieldMethod,
shieldedTransferMethod, unshieldMethod, shieldFromAssetLockMethod,
shieldedWithdrawalMethod and the appropriate expectedType/logPrefix) so shared
decoded-type guards, validation and logging live in one place.

In `@packages/wasm-dpp2/src/shielded/mod.rs`:
- Around line 28-33: Replace the post-validation call that uses expect("checked
length above") with unwrap() for stylistic consistency: after you validate
bundle_commitment.len() != 32 and return an error, use unwrap() when
converting/creating the fixed-size array (the same spot currently calling
expect) so the code relies on the prior check and matches the project's
validation style (refer to the bundle_commitment length check and the conversion
site where expect("checked length above") is used).

In `@packages/wasm-dpp2/src/shielded/shielded_transfer_transition.rs`:
- Around line 88-116: Add a round-trip unit test exercising the wasm ABI:
construct a ShieldedTransferTransitionWasm instance, call to_bytes(), pass the
bytes into from_bytes() and assert the resulting ShieldedTransferTransitionWasm
equals the original; also include a JSON round-trip by calling to_json() and
verifying the serialized value round-trips (or matches expected golden JSON),
and verify to_state_transition() produces the expected StateTransition variant.
Target the wasm-facing symbols to_bytes, from_bytes, to_json,
to_state_transition and assert equality of the core inner
StateTransition::ShieldedTransfer data to catch wire-format or variant
regressions.

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro

Run ID: 2bdbcf86-45ca-47c6-ba00-fc5f4eeab635

📥 Commits

Reviewing files that changed from the base of the PR and between 037c387 and c5325c9.

📒 Files selected for processing (16)

• packages/js-dash-sdk/src/SDK/Client/Platform/Platform.ts
• packages/js-dash-sdk/src/SDK/Client/Platform/methods/shielded/shield.ts
• packages/js-dash-sdk/src/SDK/Client/Platform/methods/shielded/shieldFromAssetLock.ts
• packages/js-dash-sdk/src/SDK/Client/Platform/methods/shielded/shieldedTransfer.ts
• packages/js-dash-sdk/src/SDK/Client/Platform/methods/shielded/shieldedWithdrawal.ts
• packages/js-dash-sdk/src/SDK/Client/Platform/methods/shielded/unshield.ts
• packages/wasm-dpp/src/identity/state_transition/transition_types.rs
• packages/wasm-dpp/src/state_transition/state_transition_factory.rs
• packages/wasm-dpp2/src/lib.rs
• packages/wasm-dpp2/src/shielded/mod.rs
• packages/wasm-dpp2/src/shielded/shield_from_asset_lock_transition.rs
• packages/wasm-dpp2/src/shielded/shield_transition.rs
• packages/wasm-dpp2/src/shielded/shielded_transfer_transition.rs
• packages/wasm-dpp2/src/shielded/shielded_withdrawal_transition.rs
• packages/wasm-dpp2/src/shielded/unshield_transition.rs
• packages/wasm-dpp2/src/state_transitions/base/state_transition.rs