feat: add bindings for more getters for BeaconStateView by guha-rahul · Pull Request #189 · ChainSafe/lodestar-z

guha-rahul · 2026-01-22T21:20:17Z

implemented bindings for

getValidator
getValidatorStatus
getValidatorCount
getActiveValidatorCount
getBeaconProposer
getBeaconProposers
getBeaconProposersPrevEpoch
getBeaconProposersNextEpoch
getIndexedSyncCommitteeAtEpoch
getBlockRootAtSlot
getBlockRoot
isMergeTransitionComplete
getRandaoMix
getHistoricalSummaries
getPendingDeposits
getPendingPartialWithdrawals
getPendingConsolidations
getProposerLookahead
getSingleProof
isValidVoluntaryExit
getVoluntaryExitValidity
proposerRewards
processSlots
previousDecisionRoot
currentDecisionRoot
nextDecisionRoot
getShufflingDecisionRoot

gemini-code-assist · 2026-01-22T21:20:31Z

Summary of Changes

Hello @guha-rahul, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request introduces N-API bindings for the processSlots functionality, enabling JavaScript/TypeScript applications to interact with the core state transition logic for advancing the beacon state. This enhancement provides a mechanism to process multiple slots efficiently, with an option to control cache transfer during the state cloning process, thereby expanding the capabilities of the bindings.

Highlights

New N-API Binding for processSlots: A new N-API function, BeaconStateView_processSlots, has been introduced in beacon_state_view.zig. This function allows processing slots from the current state to a target slot, returning a new BeaconStateView.
TypeScript Type Definitions: Corresponding TypeScript type definitions for the processSlots method and its optional parameters (ProcessSlotsOpts) have been added in index.ts, improving type safety and developer experience.
Demo/Test Usage: A demo call to processSlots has been added in demo.ts to showcase the usage of the new functionality and measure its execution duration.

🧠 New Feature in Public Preview: You can now enable Memory to help Gemini Code Assist learn from your team's feedback. This makes future code reviews more consistent and personalized to your project's style. Click here to enable Memory in your admin console.

Using Gemini Code Assist

The full guide for Gemini Code Assist can be found on our documentation page, here are some quick tips.

Invoking Gemini

You can request assistance from Gemini at any point by creating a comment using either /gemini <command> or @gemini-code-assist <command>. Below is a summary of the supported commands on the current page.

Feature	Command	Description
Code Review	`/gemini review`	Performs a code review for the current pull request in its current state.
Pull Request Summary	`/gemini summary`	Provides a summary of the current pull request in its current state.
Comment	@gemini-code-assist	Responds in comments when explicitly tagged, both in pull request comments and review comments.
Help	`/gemini help`	Displays a list of available commands.

Customization

To customize Gemini Code Assist for GitHub experience, repository maintainers can create a configuration file and/or provide a custom code review style guide (such as PEP-8 for Python) by creating and adding files to a .gemini/ folder in the base of the repository. Detailed instructions can be found here.

Limitations & Feedback

Gemini Code Assist may make mistakes. Please leave feedback on any instances where its feedback is incorrect or counter productive. You can react with 👍 and 👎 on @gemini-code-assist comments. If you're interested in giving your feedback about your experience with Gemini Code Assist for Github and other Google products, sign up here.

You can also get AI-powered code generation, chat, as well as code reviews directly in the IDE at no cost with the Gemini Code Assist IDE Extension.

Review the Privacy Notices, Generative AI Prohibited Use Policy, Terms of Service, and learn how to configure Gemini Code Assist in GitHub here. Gemini can make mistakes, so double check it and use code with caution. ↩

gemini-code-assist

Code Review

This pull request introduces N-API bindings for the processSlots function, allowing it to be called from JavaScript. The changes are well-structured, including the core Zig implementation, TypeScript type definitions, and a new test case. The code is clean and follows the existing patterns. I have one suggestion to improve adherence to the repository's style guide for code clarity.

gemini-code-assist · 2026-01-22T21:21:57Z

+        if (try options_arg.typeof() == .object and try options_arg.hasNamedProperty("dontTransferCache")) {
+            dont_transfer_cache = try (try options_arg.getNamedProperty("dontTransferCache")).getValueBool();
+        }


To improve readability and align with the repository's style guide, it's better to split this compound if condition into nested if statements. This makes the control flow clearer and easier to reason about.

if (try options_arg.typeof() == .object) { if (try options_arg.hasNamedProperty("dontTransferCache")) { dont_transfer_cache = try (try options_arg.getNamedProperty("dontTransferCache")).getValueBool(); } }

References

The style guide (lines 130-132) advises against compound conditions, recommending nested if/else branches to make it easier for the reader to verify that all cases are handled. ^(link)

…hdrawals

spiral-ladder

Nice! Some comments

spiral-ladder · 2026-01-27T07:52:08Z

@@ -9,6 +9,17 @@ const SignedBlock = state_transition.SignedBlock;
 const isExecutionEnabledFunc = state_transition.isExecutionEnabled;
 const computeUnrealizedCheckpoints = state_transition.computeUnrealizedCheckpoints;
 const getEffectiveBalanceIncrementsZeroInactiveFn = state_transition.getEffectiveBalanceIncrementsZeroInactive;
+const processSlotsFn = state_transition.state_transition.processSlots;


Suggested change

const processSlotsFn = state_transition.state_transition.processSlots;

const processSlots = state_transition.state_transition.processSlots;

do we need this rename?

every other function uses fn and i noticed isExecutionEnabledFunc is different so i should change it right?

spiral-ladder · 2026-01-27T11:22:31Z

+    const cached_state = try env.unwrap(CachedBeaconState, cb.this());
+    const slot: u64 = @intCast(try cb.arg(0).getValueInt64());
+
+    var dont_transfer_cache = false;


I know this is because of do_not_transfer_cache in our native layer, but I think it's bad to have double negatives as bool, and we should just have transfer_cache in a future refactor PR. transfer_cache = true is clearer than do_not_transfer_cache = false.

Just noting this down first, no changes needed for this PR - we can change it together with the native part

spiral-ladder · 2026-01-27T13:09:35Z

+    pub fn fromString(s: []const u8) ?ValidatorStatus {
+        if (std.mem.eql(u8, s, "pending_initialized")) return .pending_initialized;
+        if (std.mem.eql(u8, s, "pending_queued")) return .pending_queued;
+        if (std.mem.eql(u8, s, "active_ongoing")) return .active_ongoing;
+        if (std.mem.eql(u8, s, "active_exiting")) return .active_exiting;
+        if (std.mem.eql(u8, s, "active_slashed")) return .active_slashed;
+        if (std.mem.eql(u8, s, "exited_unslashed")) return .exited_unslashed;
+        if (std.mem.eql(u8, s, "exited_slashed")) return .exited_slashed;
+        if (std.mem.eql(u8, s, "withdrawal_possible")) return .withdrawal_possible;
+        if (std.mem.eql(u8, s, "withdrawal_done")) return .withdrawal_done;
+        return null;
+    }


Similarly, I think this can be replaced with std.meta.stringToEnum

- implemented bindings for ``` getValidator getValidatorStatus getValidatorCount getActiveValidatorCount getBeaconProposer getBeaconProposers getBeaconProposersPrevEpoch getBeaconProposersNextEpoch getIndexedSyncCommitteeAtEpoch getBlockRootAtSlot getBlockRoot isMergeTransitionComplete getRandaoMix getHistoricalSummaries getPendingDeposits getPendingPartialWithdrawals getPendingConsolidations getProposerLookahead getSingleProof isValidVoluntaryExit getVoluntaryExitValidity proposerRewards processSlots previousDecisionRoot currentDecisionRoot nextDecisionRoot getShufflingDecisionRoot ```

guha-rahul added 2 commits January 23, 2026 02:36

feat: add process_slot

c022690

fix: add computeUnrealizedCheckpoints

0c13d62

guha-rahul requested a review from a team as a code owner January 22, 2026 21:20

gemini-code-assist Bot reviewed Jan 22, 2026

View reviewed changes

chore : split if

dc480f6

guha-rahul changed the title ~~feat: add bindings for process_slot~~ feat: add bindings for more getters for BeaconStateView Jan 24, 2026

guha-rahul added 23 commits January 25, 2026 01:20

add proposer_rewards

83b027d

add getValidator

12a4fd3

add getValidatorStatus

c87e46b

add getValidatorCount

3620ac9

add getActiveValidatorCount

643a340

add getBeaconProposer

d88723d

add getBeaconProposers

dfb5511

add getBeaconProposersPrevEpoch

67c4972

add getBeaconProposersNextEpoch

23ee54c

add getIndexedSyncCommitteeAtEpoch

3f68f7d

add getBlockRootAtSlot

0cdeb8e

add getBlockRoot

6a1de82

add isMergeTransitionComplete

10a9c05

add getRandaoMix

652110a

add getHistoricalSummaries

2bf2a26

fix: use bulk read to getHistoricalSummaries

1643426

get getPendingDeposits

dc6ff1d

fix: replace hardcode with length (incase of BLS)

65581d5

add getPendingPartialWithdrawals

142ae67

add getPendingConsolidations

fb43ec5

add getProposerLookahead

90007d3

Fix typed array casting and bounds in N-API number slice conversion

576b678

add getSingleProof

5a7d3b3

guha-rahul added 8 commits January 26, 2026 16:32

remove deserialisation in getPendingDeposits and getPendingPartialWit…

d2ea3f0

…hdrawals

add isValidVoluntaryExit

803eda4

add getVoluntaryExitValidity

7e75fc9

fix enum

ffc8a47

fix: select body instead of hashing the block

c1e45b0

add defaultValue to BeaconBlock

db840d3

add stateRoot to block

f3a3a59

add Decision roots methods/getters

1a40163

spiral-ladder reviewed Jan 27, 2026

View reviewed changes

spiral-ladder mentioned this pull request Jan 28, 2026

(do not merge) comptime fn name guarantees for napi bindings #198

Closed

guha-rahul added 7 commits January 28, 2026 20:14

remove stray ssz

b70aa5e

nit: use default struct values

7869560

use tagName

ff29b36

use std.meta.stringToEnum

3722cfa

Merge branch 'napi' into bindings/process_slot

7b2575a

add processSlots and proposerRewards in register

9966651

add comptime string gurantee

8063296

guha-rahul requested a review from spiral-ladder January 28, 2026 15:54

remove unused interfaces

dfd8174

wemeetagain approved these changes Jan 29, 2026

View reviewed changes

wemeetagain merged commit cfc06cb into ChainSafe:napi Jan 29, 2026
1 check passed

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

feat: add bindings for more getters for BeaconStateView#189

feat: add bindings for more getters for BeaconStateView#189
wemeetagain merged 42 commits intoChainSafe:napifrom
guha-rahul:bindings/process_slot

guha-rahul commented Jan 22, 2026 •

edited

Loading

Uh oh!

gemini-code-assist Bot commented Jan 22, 2026

Uh oh!

gemini-code-assist Bot left a comment

Uh oh!

gemini-code-assist Bot Jan 22, 2026

Uh oh!

spiral-ladder left a comment

Uh oh!

spiral-ladder Jan 27, 2026

Uh oh!

guha-rahul Jan 28, 2026

Uh oh!

spiral-ladder Jan 27, 2026

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

spiral-ladder Jan 27, 2026

Uh oh!

Uh oh!

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

3 participants

	const processSlotsFn = state_transition.state_transition.processSlots;
	const processSlots = state_transition.state_transition.processSlots;

Conversation

guha-rahul commented Jan 22, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

gemini-code-assist Bot commented Jan 22, 2026

Summary of Changes

Highlights

Footnotes

Uh oh!

gemini-code-assist Bot left a comment

Choose a reason for hiding this comment

Code Review

Uh oh!

gemini-code-assist Bot Jan 22, 2026

Choose a reason for hiding this comment

Uh oh!

spiral-ladder left a comment

Choose a reason for hiding this comment

Uh oh!

spiral-ladder Jan 27, 2026

Choose a reason for hiding this comment

Uh oh!

guha-rahul Jan 28, 2026

Choose a reason for hiding this comment

Uh oh!

spiral-ladder Jan 27, 2026

Choose a reason for hiding this comment

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

spiral-ladder Jan 27, 2026

Choose a reason for hiding this comment

Uh oh!

Uh oh!

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

3 participants

guha-rahul commented Jan 22, 2026 •

edited

Loading