nbconvert does not output in current directory by default

[matthiaskoenig]

In older versions nbconvert wrote the output files in the current directory.
This is also stated in the documentation

jupyter nbconvert --help
...
--output-dir=<Unicode> (FilesWriter.build_directory)
    Default: ''
    Directory to write output to.  Leave blank to output to the current
    directory

Default is blank, so should output to the current directory.

I updated jupyter to 4.2.0 and now the output is written by default next to the input files.
There is mismatch between documentation and actual behavior (which changed compared to earlier versions).

[mpacer]

There are a number of other issues related to this — e.g., #337, #293.

The docs should change to reflect the current state. I'll make a note of that.

If you wish to recover this default behaviour, you can go to your ~/.jupyter/jupyter_nbconvert_config.py and add the line c.FilesWriter.build_directory='.' and it will change it back to the older default.

Then if you wanted to recover the new default behaviour you would need to add the flag --output-dir '' to your command line invocation.

[mpacer]

opened #450 to address the doc/help issue.