AMM Unit tests: rounding down of equal asset deposit LPToken calculation

[ckeshava]

High Level Overview of Change

This PR exercises a specific portion of the AMMHelpers.cpp file. It triggers a downward rounding of LPTokens in adjustLPTokens function in the AMMHelpers.cpp file.

Context of Change

Type of Change

• [ ] Bug fix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to not work as expected)
• [ ] Refactor (non-breaking change that only restructures code)
• [ ] Performance (increase or change in throughput and/or latency)
• [x] Tests (you added tests for code that already exists, or your new feature included in this PR)
• [ ] Documentation update
• [ ] Chore (no impact to binary, e.g. .gitignore, formatting, dropping support for older tooling)
• [ ] Release

API Impact

• [ ] Public API: New feature (new methods and/or new fields)
• [ ] Public API: Breaking change (in general, breaking changes should only impact the next api_version)
• [ ] libxrpl change (any change that may affect libxrpl or dependents of libxrpl)
• [ ] Peer protocol change (must be backward compatible or bump the peer protocol version) No impact on performance. No change to APIs

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 70.9%. Comparing base (24a275b) to head (8f7dbfb).

Additional details and impacted files

[](https://app.codecov.io/gh/XRPLF/rippled/pull/4982?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=XRPLF) ```diff @@ Coverage Diff @@ ## develop #4982 +/- ## ======================================= Coverage 70.9% 70.9% ======================================= Files 796 796 Lines 66727 66727 Branches 10981 10976 -5 ======================================= + Hits 47333 47338 +5 + Misses 19394 19389 -5 ``` [see 2 files with indirect coverage changes](https://app.codecov.io/gh/XRPLF/rippled/pull/4982/indirect-changes?src=pr&el=tree-more&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=XRPLF) [](https://app.codecov.io/gh/XRPLF/rippled/pull/4982?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=XRPLF)

[HowardHinnant]

This looks good to me. But I was hoping it would hit these lines: https://app.codecov.io/gh/XRPLF/rippled/pull/4982/blob/src/ripple/app/misc/impl/AMMHelpers.cpp#L171. And I don't have a good explanation as to why it didn't. Nevertheless, this looks like a good addition to me.

[ckeshava]

@HowardHinnant I have updated the numbers so that the execution hits the necessary lines.

I expected 10'000.1 to be rounded down to 10'000 and consequently hit the said line. I think my debugger is malfunctioning.

[ckeshava]

Hello, the commit message could be: Unit test to examine the rounding behavior of equal-asset deposits with tfLPToken flag

@ximinez