Column attribute best_fit is not set correctly

[zerowaitstate]

There is a serializable attribute on worksheet columns called best_fit which tells excel whether to automatically resize a column. This is apparently set to "true" when the column width is manually set via width=. This would seem to be opposite the expected behavior, especially when considering the attribute documentation on best_fit. I checked back through the commit history and this is not a regression; this bug seems to have been there since the original column code was written.

caxlsx/lib/axlsx/workbook/worksheet/col.rb

Line 117 in 6556c62

@custom_width = @best_fit = !v.nil?

Before doing a PR I wanted to ask if I am possibly misunderstanding what this attribute does.

[zerowaitstate]

This is the doc on the attribute

caxlsx/lib/axlsx/workbook/worksheet/col.rb

Lines 39 to 42 in 6556c62

	# Flag indicating if the specified column(s) is set to 'best fit'. 'Best fit' is set to true under these conditions:
	# The column width has never been manually set by the user, AND The column width is not the default width
	# 'Best fit' means that when numbers are typed into a cell contained in a 'best fit' column, the column width should
	# automatically resize to display the number. [Note: In best fit cases, column width must not be made smaller, only larger. end note]

[kiskoza]

Hi @zerowaitstate. Let me know if I get it right: the best_fit attribute does not have an instant visual effect, but it defines how the cell should handle when you edit it later and provide a long(er) number.

By default, Excel has "best fit" as true on every cell, you can try it out with an empty sheet. I think the original code meant to keep this behaviour for caxlsx generated cells with pre-calculated widths. It looks like the comments are describing how Excel uses this flag, not how caxlsx is trying to set it.

I can see your point on why do you want to turn this off, so I'd suggest adding a global config to caxlsx to auto-enable best fit or not (default should be the current behaviour). We're doing something similar with No autowidth config.