While we might never be able to have 100% of our code strict, we can at
the very least do it for all of our tests. This ensures that our tests
are using our API with the types as intended by the test author, and not
silently be cast to what our API requires.
This is a start in addressing issue #2965 (and earlier issue #749). Chart Titles are usually entered as strings or Rich Text strings, and PhpSpreadsheet supports that. They can also be entered as formulas (typically a pointer to a cell with the title text), and, not only did PhpSpreadsheet not support that, it threw an exception when reading a spreadsheet that did so.
This change does:
- eliminate the exception
- set a static chart title when it can determine it from the Xml
This change does not:
- fully support dynamic titles (e.g. if you change the contents of the source cell, or delete or insert cells or rows or columns)
- permit the user to set the title to a formula
- allow the use of formulas when writing a chart title to a spreadsheet
- provide styling for titles when it has read them as a formula