test flow() atomicity on later-transfer failure

[thedavidmeister]

Summary

Pins the documented atomicity invariant on IFlowV5.flow(): when a later transfer in the same flow reverts, the entire flow reverts and no earlier transfer's effects persist.

The test mixes a valid ERC20 transfer with an ERC1155 transfer that fails the from-allowed check. The outer revert reason MUST be the inner failure's selector — that proves the inner revert was not caught and squashed by a wrapper.

EVM transaction-level rollback handles the actual state revert; this test exists to lock the revert-propagation invariant against a future change that wraps inner calls in try/catch.

Closes #318.

Test plan

• testFlowAtomicRollbackOnLaterTransferFailure — 100 fuzz runs

🤖 Generated with Claude Code

Summary by CodeRabbit

• Tests
  • Added test coverage to verify atomic rollback behavior in flow transfers, ensuring earlier successful transfers are reverted when subsequent transfers fail.

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Caution

Review failed

The pull request is closed.

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: ASSERTIVE

Plan: Pro

Run ID: edaa42db-f162-46ee-b0db-c53eda17211b

📥 Commits

Reviewing files that changed from the base of the PR and between f434ae7 and 880275b.

📒 Files selected for processing (1)

• test/src/concrete/Flow.transfer.t.sol

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Walkthrough

This PR adds a new fuzz test testFlowAtomicRollbackOnLaterTransferFailure to the Flow transfer test suite. The test verifies that IFlowV5.flow() atomically processes transfers: when a later transfer fails, the entire batch reverts and earlier successful transfers are rolled back without leaving observable state changes.

Changes

Atomic Rollback Test

Layer / File(s)	Summary
Test Implementation test/src/concrete/Flow.transfer.t.sol	Fuzz test that constructs a flow with a mocked-to-succeed ERC20 transfer and a failing ERC1155 transfer (disallowed sender), mocks the ERC20 call, and asserts the entire flow() call reverts with UnsupportedERC1155Flow.selector, confirming atomicity and rollback.

Possibly related issues

• [A22-3] [LOW] IFlowV5.flow() atomicity invariant has no dedicated test #318 — The test implementation directly satisfies the proposed atomicity test case for IFlowV5.flow() documented in the linked issue, verifying the invariant that any failure during the flow must revert the entire batch and leave token state unchanged.

🎯 2 (Simple) | ⏱️ ~8 minutes

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch 2026-05-05-issue-318-flow-atomicity-test

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