When a spreadsheet containing defined names is cloned, the worksheets pointed to by the defined names in the cloned spreadsheet are actually clones of the intended worksheets. Fix this, add tests.
In issue #4557, the user complains, with some justification, about the way Excel handles certain calculations. We are not able to help with that problem. However, the user also notes a problem in Shared/Date when `isDateTime` has to evaluate a cell whose calculated value is an array. This is solved by flattening the calculated result to a single value.
It became obvious while working on this change that the code to set `instanceArrayReturnType` was kind of awkward. Simpler methods `returnArrayAsArray` and `returnArrayAsValue` are added to `Spreadsheet`. Even these started out a bit awkward because `Spreadsheet::calculationEngine` was defined as nullable, which really isn't true. It is allocated by the constructor, and never freed except in the destructor. It is no longer nullable.
Spreadsheet clone already copies Calculation instanceArrayReturnType property. It should also copy some other Calculation instance properties, namely suppressFormulaErrors, calculationCacheEnabled, and branchPruningEnabled.
Since we have a usable copy method in Spreadsheet, this is probably overkill, especially with serialization now allowed. Nevertheless, I would prefer to not artificially render a standard Php operation (clone) unusable.
kemo
oleibman