* Additional Unit Tests for XIRR and XNPV
See discussion in issue #3297. Excel result disagreed with PhpSpreadsheet, but it seems apparent that the error is Excel's. Although we have other test cases where Excel and PhpSpreadsheet disagree, those have so far been cases where Excel cannot give an answer because its algorithm does not converge, which is possible for any algorithm. In the issue in question, Excel seems to converge to a different answer; this is different than the other exceptions, and so deserves documentation with a formal test case. The discussion also mentions some cases where XNPV seems to give the wrong result in Excel, and those cases are added for XNPV.
* Scrutinizer
Whatever.
* Fix Unintential Deprecated Calls in Tests - FINANCIAL
I think it's best to install these before PR #3166. There are no changes to source code, only to doc-blocks and to test members which continue to inadvertently use calls to deprecated functions.
* Change Tests to Run in Spreadsheet Context
Found and fixed some problems with how MIRR handles errors.
* Extract remaining Financial function unit tests into separate test classes for each function
This makes it easier to manage unit tests if they are individual files rather than all in a single file
It also provides a stepping stone toward making it easier to test Excel functions when Excel errors no longer return a string, but an actual Excel exception that can be handled more cleanly
oleibman
Adrien Crivelli
Mark Baker