Unable to fetch rows of a sheet with more than 31 characters in its name.

[dosaki]

Description
Unable to fetch a sheet with more than 31 characters in its name.

I know this is not supported by Microsoft Excel but this issue prevents a user from handling xlsx files produced by other tools (LibreOffice or Google Sheets).

The reason for this is in File.Rows() when getting the sheet from f.sheetMap (see github.com/360EntSecGroup-Skylar/excelize/rows.go:151).

The problem here is that f.sheetMap has the original sheet name but we're trying to find it via the truncated sheet name (trimSheetName(sheet)). Naturally, this may not be possible when the sheet name doesn't respect the 31 character limit.

#249 mentions something about 31 characters, but I don't understand Chinese so I cannot be sure if it's related at all.

Steps to reproduce the issue:

1. Download this zip
2. Extract the xlsx and the go file.
3. Run the go file: go run main.go

Describe the results you received:
Excelize cannot find the sheet "abcdefghijklmnopqrstuvwxyz0123456789"

$ go run main.go 
Err is nil: false
sheet abcdefghijklmnopqrstuvwxyz0123456789 is not exist

Describe the results you expected:
I expected the sheet "abcdefghijklmnopqrstuvwxyz0123456789" to be found.

$ go run main.go 
Err is nil: true
nil

Output of go version:

go version go1.13.5 linux/amd64

Excelize version or commit ID:

5f3a4bc39f9cf2987104ffe57242a0526cdd9158

Environment details (OS, Microsoft Excel™ version, physical, etc.):
Linux

[xuri]

Hi @dosaki, thanks for your feedback. I propose keeping the 31-character limit to prevent mostly unexpected file corruption, use abbreviations for words in the names, devise a code-number system that ties to a longer name listed in a worksheet, etc.

[dosaki]

I don't think getting rid of the 31 character limit is a good solution but if the sheet map is also capped to 31 characters then this would resolve the issue?

[xuri]

Currently, if you save or export the workbook by LibreOffice (7.5.2.2) and Google Sheets, the sheet name of more than 31 characters will be trimmed, so I think we need to keep this maximum limit for better compatibility. I've closed this issue, if you have any questions, please me know, and we can reopen this anytime.

[Aprax14]

Hi @xuri , I agree with you that the 31-chars limit should be enforced, however I noticed that when opening a file created by a third-party application with a sheet name exceeding 31 characters, it's currently impossible to even rename that sheet using SetSheetName, because the validation also rejects the source parameter. This effectively makes the file unusable through excelize.

Would you be open to removing the name validation only on the source parameter of SetSheetName? This way excelize would still enforce the 31-chars limit, but would allow users to rename non-compliant sheets to valid ones. The change is minimal, if you agree I would be happy to submit a PR.

[xuri]

Okay, sure. We can removing the name validation only on the source parameter of SetSheetName. Contribution are welcome.