utils/enh/roundAmountByCurrency

[H-C-21]

Summary by CodeRabbit

• Bug Fixes
  • Pricing amounts in API responses are now calculated with proper currency-specific accuracy, improving precision across all supported currencies.

[coderabbitai]

Walkthrough

The roundAmountByCurrency function in the Price module was refactored to dynamically apply currency-specific rounding accuracy instead of hardcoding EUR accuracy and returning original amounts for all other currencies, directly affecting PriceAPIEntity JSON serialization behavior.

Changes

Cohort / File(s)	Summary
Price Rounding Logic lib/mobility-core/src/Kernel/Types/Price.hs	Updated roundAmountByCurrency to use getAccuracy currency for all currencies, removing hardcoded EUR-specific logic and conditional fallback behavior. Changes JSON serialization of PriceAPIEntity amount field.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~12 minutes

Poem

🐰 A currency tale, precise and true,
No hardcoded EUR in our view,
Each coin now rounds by its own measure,
Accuracy's a flexible treasure! ✨

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 inconclusive)

Check name	Status	Explanation	Resolution
Title check	❓ Inconclusive	The title 'utils/enh/roundAmountByCurrency' is a branch name format rather than a descriptive pull request title that clearly summarizes the main change.	Use a descriptive title that explains the change, such as 'Apply currency-specific rounding to roundAmountByCurrency' or 'Support dynamic currency rounding in roundAmountByCurrency'.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch utils/enh/roundAmountByCurrency

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[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against the current code and only fix it if needed.

Inline comments:
In `@lib/mobility-core/src/Kernel/Types/Price.hs`:
- Around line 174-175: The ToJSON instance for PriceAPIEntity is currently using
roundAmountByCurrency (which applies getAccuracy and makes INR accuracy 0),
causing INR amounts to lose paise; change the ToJSON PriceAPIEntity
implementation to serialize PriceAPIEntity.amount using the raw HighPrecMoney
value (or a new identity-preserving serializer) instead of calling
roundAmountByCurrency, and move rounding logic into a separate display formatter
(e.g., roundForDisplay or formatAmountForCurrency) used only by UI/display
paths; ensure references to roundAmountByCurrency, getAccuracy,
PriceAPIEntity.amount and the ToJSON PriceAPIEntity instance are updated,
add/adjust unit or integration tests to assert full precision is preserved for
INR/USD serialization, and if the rounding change is intentional, add a release
note documenting the precision break for INR consumers.

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

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

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ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: 0aef8d13-85f5-40fe-bed8-7b83ed1ffc9a

📥 Commits

Reviewing files that changed from the base of the PR and between 490d6ed and 63cab63.

📒 Files selected for processing (1)

• lib/mobility-core/src/Kernel/Types/Price.hs

[coderabbitai]

⚠️ Potential issue | 🟠 Major

🧩 Analysis chain

🏁 Script executed:

#!/bin/bash
# Find all usages of roundAmountByCurrency and PriceAPIEntity to assess blast radius.
rg -nP -C3 '\broundAmountByCurrency\b'
echo '----'
rg -nP -C2 '\bPriceAPIEntity\b' --type=hs
echo '----'
# Look for tests/snapshots that may pin amount formatting for INR/USD.
rg -nP -C2 '"amount"\s*[:=]' --type=hs -g '!**/dist*/**'
echo '----'
# Any explicit references to mkPriceFromAPIEntity (potential lossy round-trip).
rg -nP -C3 '\bmkPriceFromAPIEntity\b'

Repository: nammayatri/shared-kernel

Length of output: 3747

---

INR amounts will lose sub-unit precision in PriceAPIEntity JSON serialization.

roundAmountByCurrency now rounds all currency amounts using getAccuracy: INR=0 (whole rupees), USD=2, EUR=2. This affects the ToJSON PriceAPIEntity instance at line 170, which serializes every PriceAPIEntity.amount rounded.

For INR, this is a breaking change: any API consumer expecting fractional rupee amounts (paise) will now receive whole rupees, with sub-unit precision silently lost via rounding.

Verify:

• Is this rounding intentional for the API contract, or should PriceAPIEntity JSON preserve full precision while using getAccuracy only for display formatting elsewhere?
• Are there snapshot tests or integration tests that validate API response precision for INR/USD?
• If intentional, add a release note explaining the precision change for INR consumers.

🤖 Prompt for AI Agents

Verify each finding against the current code and only fix it if needed.

In `@lib/mobility-core/src/Kernel/Types/Price.hs` around lines 174 - 175, The
ToJSON instance for PriceAPIEntity is currently using roundAmountByCurrency
(which applies getAccuracy and makes INR accuracy 0), causing INR amounts to
lose paise; change the ToJSON PriceAPIEntity implementation to serialize
PriceAPIEntity.amount using the raw HighPrecMoney value (or a new
identity-preserving serializer) instead of calling roundAmountByCurrency, and
move rounding logic into a separate display formatter (e.g., roundForDisplay or
formatAmountForCurrency) used only by UI/display paths; ensure references to
roundAmountByCurrency, getAccuracy, PriceAPIEntity.amount and the ToJSON
PriceAPIEntity instance are updated, add/adjust unit or integration tests to
assert full precision is preserved for INR/USD serialization, and if the
rounding change is intentional, add a release note documenting the precision
break for INR consumers.