OMEdit behaves weirdly when opening files in directories with accented letters

[casella]

A student today reported me a weird situation: he had a very short .mo file, that looked 100% kosher when inspected with a text editor, but he couldn't load it in OMEdit.

He brought me a memory stick with the file, and in fact when I tried to load it I also experienced this strange behaviour.

After some analysis it turned out that the directory the file was in had one Italian accented letter in it.

This is similar to what was reported in #5192, though in this case there is no crash; on the contrary, nothing happens when you click OK in the Load File selection window. Which is also quite weird.

The student was particularly puzzled because he previously saw that directories with spaces were ok, so he didn't thing of accented letters.

I'm not sure supporting these directories, which is the goal of #5192 and #4504, will be an easy fix.

I think for the time being OMEdit should issue a meaningful error message when trying to deal with filenames containing special characters for operations such as loading files, saving files, and selecting the working directory.

@adeas31, could you put some check in those operations, that give an error message such as:

The filename/directory name contains special or accented characters, which are still not fully supported by OMEdit. Please only use filenames with ASCII characters (spaces are allowed)

[adeas31]

Hopefully this works fine with 69a67b2/OpenModelica.

[adeas31]

Francesco can you test this with the latest nightly?

[casella]

Seems to be working fine now. I can no longer retrieve the original test case, but I made a new one (hopefully) with the same features and it worked fine.