Won't read non-lowercase .XLSX or .xlsm files

[apjanke]

Looks like the code for identifying the file type is being case-sensitive with extensions, so it will open .xlsx files but not .XLSX.

> read_excel("epoch-1900.XLSX")
Error: Don't know how to parse extension XLSX

Since the extension-based file type detection on platforms Excel runs on is typically case-insensitive, it seems like read_excel should be too, with respect to detecting file formats.

It won't read .xlsm files, either. They're the same format as .xlsx, just with macros enabled.

> read_excel("with-macro.xlsm")
Error: Don't know how to parse extension xlsm

[hadley]

Want to try a pull request? It's a fairly simple fix

[apjanke]

Sure! Give me a little time, though; I'm an R newbie.

[apjanke]

All right, made a pull request for this, #20.