%edit editorhook fails if path has spaces #14961

Notepad++ editorhook doesn't work for %edit if you try to edit an object from a file whose path has spaces.

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Diagnosis

The %edit magic single-quotes the path if it has spaces, before passing to the editor hook:

Then the default editor hook expects a safe filename, and joins it into a string to use in a Popen call:

(Notice that it DOES quote the editor path, conditionally, so that is an inconsistency in how it treats the two paths: )

However, the editor hooker makes an editor hook which expects the filename to be an unescaped string, and then uses shlex.quote to substitute it into a template and do the call:

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Solution

In my opinion, the responsibility of escaping should be moved down to the callee, because taking a quoted filepath is weird.

This will break people's custom hooks which correct for this bug.

• But there is already a test which calls a custom editor hook with unquoted spaces:
  

  ipython/tests/test_editorhooks.py

  Line 25 in cbac235

  get_ipython().hooks.editor("the file", 64)

• And _edit_macro also calls the editor hook without quoting:
  

  ipython/IPython/core/magics/code.py

  Lines 539 to 540 in cbac235

  	filename = self.shell.mktempfile(macro.value)
  	self.shell.hooks.editor(filename)

  
  I suspect that breaks if the temp folder is on a path with spaces.

The escaping is also not the best because it doesn't check for existing special characters. It should just use a safer call, if available.

Also, there should be more consistency between how the default and the custom process calls are done.

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Also, %edit takes the absolute path, which might lengthen error messages unnecessarily.