See issue #2116. Code for handling end of month (method couponFirstPeriodDate) needed a fix. Fixed it, confirmed it covered the reported issue with no regression problems. Then added some extra similar tests to all the callers of couponFirstPeriodDate, and ...
One new test, in COUPDAYSNC, does not agree with Excel. It also does not agree with LibreOffice. It does, however, agree with Gnumeric, and with my (hardly guaranteed) hand calculation of what the result should be. So, I'm going with it (and have added an appropriate comment to the test data). I'm glad to discuss the matter with anyone more familiar than I with how this is supposed to work - those 360-day years are killers.
* Additional unit tests and rationalisation for Financial Functions
* Providing a series of sample files for Financial functions
* Refactor the last of the existing Financial functions
* Some more unit tests with default assignments from null arguments
Co-authored-by: Adrien Crivelli <adrien.crivelli@gmail.com>
* Extract ACCRINT() and ACCRINTM() Financial functions into their own class
Implement additional validations, with additional unit tests
Add support for the new calculation method argument for ACCRINT()
* Additional tests for Amortization functions
* Start work on breaking down some of the Financial Excel functions
* Unhappy path unit tests for Treasury Bill functions
* Codebase for Treasury Bills includes logic for a different days between settlement and maturity calculation for OpenOffice; but Open/Libre Office now uses the Excel days calculation, so this discrepancy between packages is no longer required
* We've already converted the Settlement and Maturity dates to Excel timestamps, so there's no need to try doing it again when calculating the days between Settlement and Maturity
* Add Unit Tests for the Days per Year helper function
* Extract Interest Rate functions - EFFECT() and NOMINAL() - with additional validation, and unhappy path unit tests
* First pass at extracting the Coupon Excel functions
* Simplify the validation methods
* Extended unit tests to cover all combinations of frequency and basis, including leap years
Fix for COUPDAYSNC() when basis is US 360 and settlement date is the last day of the month
* Ensure that all Financial function code uses the new Helpers class for Days Per Year