Error Codes

Complete reference for all NullGraph custom errors

The NullGraph program defines 6 custom errors to handle validation failures and prevent invalid state transitions. All errors are defined in the NullGraphError enum using Anchor’s #[error_code] macro.

Location: lib.rs:579-593

Error Code Enum

#[error_code]
pub enum NullGraphError {
    #[msg("Bounty is not in the expected status")]
    InvalidBountyStatus,
    #[msg("Submission is not in the expected status")]
    InvalidSubmissionStatus,
    #[msg("Matched submission mismatch")]
    SubmissionMismatch,
    #[msg("Bounty deadline has passed")]
    BountyExpired,
    #[msg("Reward amount must be > 0")]
    InvalidRewardAmount,
    #[msg("Fee calculation overflow")]
    FeeOverflow,
}

---

InvalidBountyStatus

Code · 6000

Message · string

“Bounty is not in the expected status”

Description

Thrown when an instruction attempts to operate on a bounty that is not in the required status.

Thrown By

Show submit_to_bounty (line 125)

Validation: require!(bounty.status == 0, NullGraphError::InvalidBountyStatus)

Condition: Bounty must have status 0 (Open) to accept submissions.

Example: Attempting to submit an NKA to a bounty that is already Matched (1), Fulfilled (2), or Closed (3).

Show approve_bounty_submission (line 157)

Validation: require!(bounty.status == 1, NullGraphError::InvalidBountyStatus)

Condition: Bounty must have status 1 (Matched) to approve a submission.

Example: Attempting to approve a bounty that is still Open (0) or already Fulfilled (2) or Closed (3).

Show close_bounty (lines 233-236)

Validation: require!(bounty.status == 0 || bounty.status == 1, NullGraphError::InvalidBountyStatus)

Condition: Bounty must have status 0 (Open) or 1 (Matched) to be closed.

Example: Attempting to close a bounty that is already Fulfilled (2) or Closed (3).

Status Reference

Status	Value	Description	Valid Operations
Open	0	Accepting submissions	submit_to_bounty, close_bounty
Matched	1	Submission linked	approve_bounty_submission, close_bounty
Fulfilled	2	Payout complete	None (terminal state)
Closed	3	Refunded	None (terminal state)

Code Reference

// submit_to_bounty validation (line 125)
let bounty_status = ctx.accounts.bounty.status;
require!(bounty_status == 0, NullGraphError::InvalidBountyStatus); // Must be Open

// approve_bounty_submission validation (line 157)
require!(bounty.status == 1, NullGraphError::InvalidBountyStatus); // Must be Matched

// close_bounty validation (lines 233-236)
require!(
    bounty.status == 0 || bounty.status == 1,
    NullGraphError::InvalidBountyStatus
);

---

InvalidSubmissionStatus

Code · 6001

Message · string

“Submission is not in the expected status”

Description

Thrown when attempting to approve a submission that is not in Pending status.

Thrown By

Show approve_bounty_submission (line 164)

Validation: require!(submission.status == 0, NullGraphError::InvalidSubmissionStatus)

Condition: BountySubmission must have status 0 (Pending) to be approved.

Example: Attempting to approve a submission that has already been Approved (1) or Rejected (2).

Submission Status Reference

Status	Value	Description
Pending	0	Awaiting creator review
Approved	1	Accepted, payout executed
Rejected	2	Declined (not currently used)

Code Reference

// approve_bounty_submission validation (line 164)
let submission = &mut ctx.accounts.submission;
require!(submission.status == 0, NullGraphError::InvalidSubmissionStatus); // Must be Pending

---

SubmissionMismatch

Code · 6002

Message · string

“Matched submission mismatch”

Description

Thrown when the provided BountySubmission account does not match the bounty’s recorded matched_submission field.

Thrown By

Show approve_bounty_submission (lines 158-161)

Validation: require!(bounty.matched_submission == ctx.accounts.submission.key(), NullGraphError::SubmissionMismatch)

Condition: The submission account’s public key must exactly match bounty.matched_submission.

Example: Passing the wrong BountySubmission PDA when calling approve_bounty_submission.

Security Note

This check prevents a malicious actor from substituting a different submission during approval. The bounty’s matched_submission field is set atomically in submit_to_bounty and cannot be changed except by approving or closing the bounty.

Code Reference

// approve_bounty_submission validation (lines 158-161)
require!(
    bounty.matched_submission == ctx.accounts.submission.key(),
    NullGraphError::SubmissionMismatch
);

---

BountyExpired

Code · 6003

Message · string

“Bounty deadline has passed”

Description

Reserved for future use. Currently not thrown by any instruction.

Intended Use

This error code exists for potential future enforcement of bounty deadlines. The NullBounty.deadline field is stored on-chain but not currently validated by the program.

Potential Implementation

A future version might add deadline enforcement in submit_to_bounty:

let now = Clock::get()?.unix_timestamp;
require!(bounty.deadline >= now, NullGraphError::BountyExpired);

The frontend currently filters expired bounties based on the deadline field, but the program does not enforce this on-chain.

---

InvalidRewardAmount

Code · 6004

Message · string

“Reward amount must be > 0”

Description

Thrown when attempting to create a bounty with a zero or negative reward amount.

Thrown By

Show create_bounty (line 78)

Validation: require!(reward_amount > 0, NullGraphError::InvalidRewardAmount)

Condition: The reward_amount parameter must be greater than 0.

Example: Calling create_bounty with reward_amount: 0.

Rationale

A bounty with zero reward provides no incentive and would be pointless. This validation ensures all bounties have economic value.

Code Reference

// create_bounty validation (line 78)
require!(reward_amount > 0, NullGraphError::InvalidRewardAmount);

---

FeeOverflow

Code · 6005

Message · string

“Fee calculation overflow”

Description

Thrown when arithmetic operations during fee calculation result in overflow or underflow.

Thrown By

Show approve_bounty_submission (lines 169-174)

Validation: All fee/payout calculations use checked arithmetic:

let fee = total
    .checked_mul(fee_bps)
    .ok_or(NullGraphError::FeeOverflow)?
    .checked_div(10_000)
    .ok_or(NullGraphError::FeeOverflow)?;
let payout = total.checked_sub(fee).ok_or(NullGraphError::FeeOverflow)?;

Condition: All intermediate calculations must fit within u64 bounds.

Example: Theoretically possible with extremely large reward_amount values exceeding u64::MAX / fee_basis_points, but practically impossible with USDC’s 6-decimal precision and realistic bounty sizes.

Security Note

Using checked arithmetic prevents integer overflow attacks. Even though the inputs make overflow practically impossible, defensive programming ensures the program fails safely rather than silently producing incorrect results.

Code Reference

// approve_bounty_submission fee calculation (lines 169-174)
let protocol = &ctx.accounts.protocol_state;
let fee_bps = protocol.fee_basis_points as u64;
let total = bounty.reward_amount;
let fee = total
    .checked_mul(fee_bps)
    .ok_or(NullGraphError::FeeOverflow)?
    .checked_div(10_000)
    .ok_or(NullGraphError::FeeOverflow)?;
let payout = total.checked_sub(fee).ok_or(NullGraphError::FeeOverflow)?;

---

Error Handling in Client Code

Anchor errors can be caught and decoded in TypeScript:

import { AnchorError } from '@coral-xyz/anchor';

try {
  await program.methods.submitToBounty()
    .accounts({ /* ... */ })
    .rpc();
} catch (err) {
  if (err instanceof AnchorError) {
    switch (err.error.errorCode.code) {
      case 'InvalidBountyStatus':
        console.error('This bounty is not accepting submissions');
        break;
      case 'InvalidRewardAmount':
        console.error('Reward must be greater than 0');
        break;
      default:
        console.error('Unknown error:', err.error.errorMessage);
    }
  }
}

Error Code Summary

Code	Name	Message	Currently Used
6000	InvalidBountyStatus	Bounty is not in the expected status	Yes (3 locations)
6001	InvalidSubmissionStatus	Submission is not in the expected status	Yes (1 location)
6002	SubmissionMismatch	Matched submission mismatch	Yes (1 location)
6003	BountyExpired	Bounty deadline has passed	No (reserved)
6004	InvalidRewardAmount	Reward amount must be > 0	Yes (1 location)
6005	FeeOverflow	Fee calculation overflow	Yes (3 locations)

All Anchor custom errors automatically include the program ID and instruction context in the transaction error logs, making debugging easier.