feat: add signMetaTxCommitToBuyerOffer to meta-tx handler and mixin

[Copilot]

• Add signMetaTxCommitToBuyerOffer function to packages/core-sdk/src/meta-tx/handler.ts
• Add signMetaTxCommitToBuyerOffer method to packages/core-sdk/src/meta-tx/mixin.ts
• Add e2e test case in e2e/tests/meta-tx.test.ts: "native exchange token buyer-initiated offer"
• Fix e2e test: set sellerDeposit: "0" and drFeeAmount: "0" for native token so meta-tx relayer doesn't need to forward ETH value (InsufficientValueReceived fix)
• Add e2e test case: "non-native exchange token buyer-initiated offer" using MOCK_ERC20_ADDRESS
• Fix ERC20 test: call ensureMintedAndAllowedTokens for both fresh buyer/seller wallets before calling depositFunds (fresh wallets have 0 ERC20 balance, causing ERC20: transfer amount exceeds balance)

Original prompt

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This section details on the original issue you should resolve

<issue_title>missing method to sign metaTx for commitToBuyerOffer</issue_title>
<issue_description>- in packages\core-sdk\src\meta-tx\handler.ts, create the function signMetaTxCommitToBuyerOffer(...) using the model of signMetaTxCommitToOffer(), adapting the parameters according to those required for commitToBuyerOffer (in packages\core-sdk\src\exchanges\handler.ts)

• in packages\core-sdk\src\meta-tx\mixin.ts, create the method signMetaTxCommitToBuyerOffer using the model of signMetaTxCommitToOffer(), calling the function just added at the previous step
• in e2e\tests\meta-tx.test.ts, add some test case for signMetaTxCommitToBuyerOffer (if needed use the buyer initiated test cases from e2e\tests\core-sdk-offers.test.ts as inspiration to create the context required for the signMetaTxCommitToBuyerOffer to work)</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes missing method to sign metaTx for commitToBuyerOffer #1005

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[levalleux-ludo]

@copilot the e2e test "native exchange token buyer-initiated offer" is failing.
In the logs, I can see the error coming back from the on-chain protocol is "InsufficientValueReceived()"
Transaction data shows the called contract method is "executeMetaTransaction(address,string,bytes,uint256,bytes)" (="0x7fb34d54"). Later in the data I can see the function signature (called via a meta-transaction is "commitToBuyerOffer(uint256,(uint256,(address[],uint256[]),address))" = "60900f5e").

I understand that the protocol expect the fees (sellerDeposit + drFeeAmount) to be transfered in native currency (ETH) as value in the transaction itself, which can't be done with a meta-transaction (because the transaction is relayed and sent on-chain by another wallet than the signer). To make the test working, you have to ensure both the offer's sellerDeposit and the drFeeAmount are explicitely set to 0. Which also means that the seller doesn't need to call depositFunds prior to committing to the offer.

[Copilot]

@copilot the e2e test "native exchange token buyer-initiated offer" is failing.
In the logs, I can see the error coming back from the on-chain protocol is "InsufficientValueReceive...

Fixed in 885d8df. The test now uses sellerDeposit: "0" on the offer and feeAmount: "0" on the dispute resolver, so no ETH value needs to be forwarded by the relayer and no depositFunds call is required for the seller.

[levalleux-ludo]

@copilot please add another test case in the e2e test called "non-native exchange token buyer-initiated offer", where the offer exchangeToken is an ERC20 token (MOCK_ERC20_ADDRESS as done for the other tests)

[Copilot]

@copilot please add another test case in the e2e test called "non-native exchange token buyer-initiated offer", where the offer exchangeToken is an ERC20 token (MOCK_ERC20_ADDRESS as done for the othe...

Added in ec348e4. The new test creates a dispute resolver with an ERC20 (MOCK_ERC20_ADDRESS) fee, the buyer approves and deposits the offer price in ERC20, the seller approves and deposits the drFeeAmount in ERC20 into the protocol, then signs and relays the meta-tx. Unlike the native-token case, non-zero fees work fine here because the protocol pulls ERC20 funds from the pre-deposited protocol balance (no ETH transaction value needed).

[levalleux-ludo]

@copilot the e2e test "non-native exchange token buyer-initiated offer" is failing in the github action (https://github.com/bosonprotocol/core-components/actions/runs/22948373517/job/66616167890#step:10:634).
The reason is that 'ERC20: transfer amount exceeds balance' when the contract method "depositFunds(uint256,address,uint256)" is called (code: "0xa07fcc70" in the transaction data).
That means the wallet's balance is lower than the amount to deposit. I'm not sure if the error happens when the buyer is call depositFunds or the seller.
Both should have a sufficient balance of the exchange token to support deposit. A helper method should allow to fund the buyer and seller wallet prior to the rest of the test

[Copilot]

@copilot the e2e test "non-native exchange token buyer-initiated offer" is failing in the github action (https://github.com/bosonprotocol/core-components/actions/runs/22948373517/job...

Fixed in 72a683d. The fresh wallets from initSellerAndBuyerSDKs start with zero ERC20 balance. Added ensureMintedAndAllowedTokens([buyerFundedWallet, sellerFundedWallet], undefined, false) after wallet creation to mint tokens before the depositFunds calls.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.95%. Comparing base (030f8f3) to head (72a683d).
⚠️ Report is 4 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1006      +/-   ##
==========================================
+ Coverage   87.92%   90.95%   +3.03%     
==========================================
  Files         172      179       +7     
  Lines        7270     7288      +18     
  Branches     1366     1366              
==========================================
+ Hits         6392     6629     +237     
+ Misses        878      659     -219     

Flag	Coverage Δ
common	92.59% <ø> (ø)
core-sdk	56.48% <28.57%> (?)
e2e	85.78% <100.00%> (+0.01%)	⬆️
eth-connect-sdk	95.06% <ø> (ø)
ethers-sdk	74.45% <ø> (ø)
ipfs-storage	91.75% <ø> (?)
metadata	94.70% <ø> (ø)
unittests	60.77% <28.57%> (-24.59%)	⬇️

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[Copilot]

Pull request overview

Adds CoreSDK support for signing/relaying commitToBuyerOffer meta-transactions, plus e2e coverage for buyer-initiated offers using both native and ERC20 exchange tokens.

Changes:

• Added signMetaTxCommitToBuyerOffer signer in packages/core-sdk/src/meta-tx/handler.ts.
• Exposed signMetaTxCommitToBuyerOffer on the CoreSDK meta-tx mixin.
• Added e2e tests covering buyer-initiated offers for native and ERC20 exchange tokens (including setup fixes for fresh wallets / relayer value constraints).

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
packages/core-sdk/src/meta-tx/mixin.ts	Exposes signMetaTxCommitToBuyerOffer on the SDK mixin.
packages/core-sdk/src/meta-tx/handler.ts	Implements the meta-tx signing helper for commitToBuyerOffer.
e2e/tests/meta-tx.test.ts	Adds e2e tests validating relayed commitToBuyerOffer flows for native/ERC20 exchange tokens.