test: add scale-band assertions for sFLR, flrETH, and FtsoV2 LTS feeds

[thedavidmeister]

Closes #68
Closes #69

Both issues stem from the same root cause: hardcoded 18-decimal assumptions against external upgradeable proxies, where the only existing tests pin exact spot values rather than scale-sensitive bounds.

• testSflrRateScaleBand in LibSceptreStakedFlare.t.sol: asserts sFLR/FLR rate is in [0.1e18, 10e18]. An sFLR proxy upgrade that changes the output scale (e.g. from 1e18 to 1e9) fires this test regardless of the spot ratio.
• testFlrEthRateScaleBand in LibDineroFlrEth.t.sol: same band check for both ETH/flrETH and flrETH/ETH rates.
• testLtsFeedScaleBand in LibFtsoV2LTS.t.sol: asserts ETH/USD LTS feed value is in [1e18, 1e24], catching any wei-scale change from getFeedByIdInWei.

All three tests run at the existing pinned fork block (no new RPC dependency), add 3 tests to the suite (43 total), and all pass.

Co-Authored-By: Claude noreply@anthropic.com

Summary by CodeRabbit

• Tests

  • Added validation checks for exchange-rate scales across FLRETH, SFLR, and ETH/USD feed integrations.
  • Added safeguards to detect unexpectedly low or high rate values during testing.
  • Expanded feed tests to verify accurate decimal conversion while preserving timeout, staleness, payment, and overpayment checks.

• Improvements

  • Improved FTSO feed value handling with lossless 18-decimal precision for more reliable rate reporting.

QA

• Discriminating tests: testLtsFeedScaleBand, testSflrRateScaleBand, testFlrEthRateScaleBand (new bands) plus testFtsoV2LTSGetFeed and testFtsoV2LTSGetFeedPaid (exact pins, rewritten for the Float boundary) — shown discriminating by MUTATION rather than by a base run, because a band test by construction cannot fail on base (base has no Float boundary and the pinned fork rates sit inside the band); each was made to fail by corrupting the value it reads, see the next line. Whole suite 88 passed / 0 failed at 629ff63 in the repo's own toolchain (nix develop rainix#sol-shell, per pr-review-report sol-toolchain) with a public Flare archive RPC serving the pinned fork blocks.
• Mutations applied: src/lib/lts/LibFtsoV2LTS.sol:113 fromFixedDecimalLosslessPacked(value, 18) → , 17) → killed by testFtsoV2LTSGetFeed + testFtsoV2LTSGetFeedPaid (25225.75e18 != 2522.575e18), SURVIVED by testLtsFeedScaleBand; → , 19) → killed by the same two, band survives again; → , 22) → killed by both exact pins AND testLtsFeedScaleBand (0.2522575e18 < 1e18 lower bound); same line return value → return 0 → killed by testFtsoV2LTSGetFeed, testFtsoV2LTSGetFeedPaid, testFtsoV2LTSGetFeedExactTimeoutNotStale, testFtsoV2LTSGetFeedTimeoutZeroExactNotStale and testLtsFeedScaleBand; src/lib/flreth/LibDineroFlrEth.sol:17 return rate → return rate / 100 → killed by testGetETHPerFLRETH18 + testFlrEthRateScaleBand; src/lib/sflr/LibSceptreStakedFlare.sol:19 return rate → return rate * 50 → killed by testGetSFLRPerFLR18 + testSflrRateScaleBand. Every mutation reverted; tree verified clean after each.
• Oracle: the 18 boundary tag comes from FtsoV2Interface's own contract — getFeedByIdInWei is the wei-scaled reader, as against getFeedById, which returns an explicit _decimals — and the round-trip from LibDecimalFloat's documented lossless pack/unpack, neither derived from this repo's code. Band bounds come from external economics (an LST/underlying peg stays within 0.1x–10x of 1; ETH/USD within $1–$1e6), not from any value this repo computes.
• Category check: issue asks A) scale-band assertions for sFLR, flrETH and the FtsoV2 LTS feed ([F21] [MEDIUM] sFLR exchange-rate opcode hardcodes 18 decimals against an external upgradeable proxy, pinned only by one exact-value fork assertion #68 option (c)), B) make the type carry the scale — ftsoV2LTSGetFeed returning a Float constructed at the boundary ([F22] [MEDIUM] FtsoV2 LTS path assumes getFeedByIdInWei is 18-decimal but returns a bare uint with no decimals tag, so any future opcode consumer inherits an undetectable scale bug #69); covered A, B. Known limit, stated rather than hidden: the LTS band 1e18..1e24 is wide, so a ±1-decimal slip is caught by the sibling exact pin, not by the band; the band's distinct value is against a gross proxy-upgrade rescale and against a future maintainer re-pinning the exact literal to a new implausible value.
• Deploy: NONE, before or after merge. FlareFtsoWords deployed bytecode is byte-identical between origin/main (b634aad) and this head: sha256(deployedBytecode.object) = f8dea4c2b51aff5f6d5719b2a49ee476e97a7ea27c6db4c1bb5c4f3b9e68b9e4 and sha256(bytecode.object) = a4125919f2e474e5978afffda1cc6ca04d9a0f0435ce820fc427f24ea7847ade on BOTH, from forge build in the repo's own sol-shell. No file under src/ imports LibFtsoV2LTS — the library is reached only from tests — so the Float boundary change moves no CREATE2 address, which is also why the committed pointers/meta snapshot is unchanged. The legacy redeploy note posted on this PR in July therefore rested on a false premise: there is no bytecode to redeploy. Under the split release lifecycle no merge waits on a deploy in any case (fix: add BuildPointers.sol to build prelude so pointers drift fails copy-artifacts #162/#221), and this branch is now merged up to main (b634aad) and green on it.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: ASSERTIVE

Plan: Pro Plus

Run ID: 9d30ff19-04cc-4691-872b-b5589e43ba02

📥 Commits

Reviewing files that changed from the base of the PR and between fa4b7a6 and 629ff63.

📒 Files selected for processing (5)

• src/lib/lts/LibFtsoV2LTS.sol
• test/lib/lts/FeedConsumer.sol
• test/src/lib/flreth/LibDineroFlrEth.t.sol
• test/src/lib/lts/LibFtsoV2LTS.t.sol
• test/src/lib/sflr/LibSceptreStakedFlare.t.sol

Included review availability: Your plan includes up to 1 review per rolling hour; 0 remain after this review.

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Walkthrough

The LTS feed boundary now returns a lossless 18-decimal Float. Tests convert Float values for assertions and add scale-band checks for the LTS feed, flrETH rates, and sFLR rates.

Changes

External rate scale validation

Layer / File(s)	Summary
Tag LTS feed values with Float src/lib/lts/LibFtsoV2LTS.sol, test/lib/lts/FeedConsumer.sol	The LTS library converts the 18-decimal FTSO value to Float. FeedConsumer.getFeedValue returns Float.
Update LTS feed assertions test/src/lib/lts/LibFtsoV2LTS.t.sol	Tests convert Float results to fixed decimals before checking expected values, timeout behavior, payment, and overpayment. A scale-band test checks ETH/USD values between 1e18 and 1e24.
Validate exchange-rate scale bands test/src/lib/flreth/LibDineroFlrEth.t.sol, test/src/lib/sflr/LibSceptreStakedFlare.t.sol	Tests check flrETH and sFLR rates between 0.1e18 and 10e18.

Estimated code review effort: 2 (Simple) | ~10 minutes

Merge Risk: ⚪ Minimal · up to 629ff

The PR adds scale-sensitive assertions for sFLR, flrETH, and FtsoV2 LTS feeds without a demonstrated production-impacting issue; no actionable merge-blocking risk remains beyond normal checks and review.

Possibly related PRs

• rainlanguage/rain.flare#29: Modifies the same LibFtsoV2LTS feed path and its migration to Float values.
• rainlanguage/rain.flare#137: Modifies the same FTSO V2 LTS feed path and tests.
• rainlanguage/rain.flare#190: Covers related FTSO V2 LTS timeout and feed behavior tests.

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Linked Issues check	✅ Passed	The PR adds the requested scale-band tests for [#68] and [#69] and returns a scale-tagged Float at the LTS boundary.
Out of Scope Changes check	✅ Passed	All changes support the linked issue objectives by adding scale checks and propagating the scale-tagged Float type.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly and concisely identifies the scale-band assertions added for sFLR, flrETH, and FtsoV2 LTS feeds.

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch fix/issue-68-69-scale-band-tests

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[thedavidmeister]

🤖 ai:vetter
Reviewed 468b9c9: ready — Scale-band bounds economically sound; sFLR [0.5,1] and flrETH [1,2] are correct; tests rely on const
cost 255 — additive fork-test band assertions, self-evident

[thedavidmeister]

Rework note (human): linkage — you fully close #68 (the test-only scale-band is #68s offered option (c)), but you also Closes #69, whose fix is structural: "make the type carry the scale — have ftsoV2LTSGetFeed return a Float … constructed at the boundary." This PR is test-only and does not change that return type. Change Closes #69 → Refs #69 (keep Closes #68), or add the structural Float-at-boundary change.

[thedavidmeister]

🤖 ai:producer
Producer note: per the Rework note, the link should be Closes #68 + Refs #69 (this PR is the test-only guard; #69's structural fix — ftsoV2LTSGetFeed returning a Float constructed at the boundary — is not in this diff). Body edits are permission-blocked for this routine, so the body still says Closes #69 — please treat it as Refs #69 and relink before merge so #69 does not auto-close on partial coverage.

[thedavidmeister]

🤖 ai:producer
Producer note: rework blocked on a body-only edit — the note's option (a) is changing the body line Closes #69 → Refs #69 (keeping Closes #68), but PR-body edits (gh pr edit) are outside this routine's permitted mutations, and option (b) (the #69 structural Float-at-boundary change) would turn this test-only PR into a bytecode-changing one, which is #69's own fix to carry. Needs the human/assistant to apply the one-line relink; no code change required on this branch.

[thedavidmeister]

🤖 ai:producer
Producer note (additional relink caveat): commit db279de's message also carries 'Closes #69', and commit-message keywords fire on merge regardless of a body relink (history cannot be rewritten without a force-push, which is forbidden). So the body edit alone will not stop #69 auto-closing — land via squash with a curated message dropping that line, or re-open #69 after merge.

[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In `@test/src/lib/lts/LibFtsoV2LTS.t.sol`:
- Around line 24-29: The test only checks the current feed range and does not
resolve the untagged return value from LibFtsoV2LTS.ftsoV2LTSGetFeed. Add the
proposed scale-tagged Float at this LTS boundary so downstream callers cannot
misinterpret future scale changes; otherwise retain issue `#69` as unresolved
rather than marking it closed.

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: ASSERTIVE

Plan: Pro

Run ID: 3544f3a9-f1ea-4e1a-b8d0-cc6962ca84e8

📥 Commits

Reviewing files that changed from the base of the PR and between 2f1c6e7 and fa4b7a6.

📒 Files selected for processing (3)

• test/src/lib/flreth/LibDineroFlrEth.t.sol
• test/src/lib/lts/LibFtsoV2LTS.t.sol
• test/src/lib/sflr/LibSceptreStakedFlare.t.sol

[thedavidmeister]

🤖 ai:producer
Producer note (REQUIRES redeploy at land): commit 18712ec changes FlareFtsoWords deployed bytecode — ftsoV2LTSGetFeed now returns a scale-tagged Float at the LTS boundary. The full prelude was regenerated at this head (BuildAuthoringMeta → rain meta build → BuildPointers → forge fmt) and the committed pointers/meta snapshot is UNCHANGED, so CI stays green — but the words contract's deterministic Zoltu (CREATE2) address moves with the new bytecode and is currently undeployed, and this repo has no on-chain pin test to go red. Route the routine redeploy via pr-review-report deploy from this branch (deploy-before-merge) once review settles; do not land before the deploy-confirmed note names the landing head.

[thedavidmeister]

🤖 ai:vetter
Reviewed 18712ec: ready — closes #68 #69 — scale-band fork tests (option c of #68) plus the structural Float-at-boundary return the human rework note required for #69; all callers updated, exact-value pins preserved, bands economically sound; producer flags routine deploy-before-merge procedure at land
cost 420 — Float boundary change + fork band tests

[thedavidmeister]

🤖 ai:producer
Blocked-deploy: manual-sol-artifacts deploy run 29696238622 (suite=flare-ftso-words, branch fix/issue-68-69-scale-band-tests @ 18712ec) failed in the deploy step: script failed: vm.envAddress: environment variable DEPLOY_METABOARD_ADDRESS not found — the workflow env/secrets lack DEPLOY_METABOARD_ADDRESS, so the Zoltu redeploy cannot run until a human adds it (repo secret/var or workflow env wiring). Not re-dispatching.

[thedavidmeister]

👤 human
Ruled 18712ec: reject — executing the 2026-08-06 ruling in rainlanguage/issue-pr-cron#221 — the retired ai:blocked-deploy residue (#162) migrates to ai:reject for rework to the split release lifecycle

[thedavidmeister]

Rework note @18712ecf512ced42397d33f46c1a9f684b8b3263: rework the PR to fit the split release lifecycle — deploys never gate merges (the deploy-before-merge choreography is superseded); remove or restructure anything in the PR that waits on a deploy; where deploy constants/pins are involved, follow the *.deploy repo convention (audited code only; version ↔ snapshot ↔ pins internally consistent; tag-release lifecycle). Whatever states follow the rework (including a typed blocked-on the repo's migration if one is genuinely needed) are the producer's ordinary transitions. Executes the 2026-08-06 ruling: rainlanguage/issue-pr-cron#221

[thedavidmeister]

🤖 ai:producer
QA-block repair: appended QA-GUIDE section 8's evidence block in the PR body via pr-review-report repair-qa-block. Every byte outside the ## QA section is unchanged.

[thedavidmeister]

🤖 ai:producer
QA-block repair: replaced QA-GUIDE section 8's evidence block in the PR body via pr-review-report repair-qa-block. Every byte outside the ## QA section is unchanged.