Handle multiple buffers-or-files with `org-ql-view--complete-buffers-files`

[ahmed-shariff]

Original issue: #227 Extending conversation from #228

From the original issue, there was an problem with the initial-input for completing-read. After testing a few things, an issue with the org-ql-view--complete-buffers-files not supporting multiple files when trying to refresh org-ql-view was found. Consequently the use of completing-read-multiple was proposed in #228.

The refactor of the org-ql-view--complete-buffers-files entails the following:

• [ ] Use completing-read-multiple in org-ql-view--complete-buffers-files
• [ ] Refactor org-ql-view--contract-buffers-files to allow displaying buffers-or-files in the view buffer
  • All file names and buffers/buffer-names are normalized to allow identifying duplicates.
  • When a list is passed, if it's not one of the special cases (eg: "org-directory"), make sure it's a list of strings.
  • Remove duplicate entries if there are any (in theory this should never happen?)
  • If the value being contracted is a function and it resolves to the org-agenda-files function, contract to "org-agenda-files" instead of a function.
  • Expect the output of this function to be a list of strings, a string value, or a function.
• [ ] Refactor org-ql-view--expand-buffers-files to always return a list of string to allow displaying them in the view buffer
  • Resolve all values to a list of strings and ensure no unique values are present in them.
• Refactoring org-ql-view--expand-buffers-files will impact org-ql-view--link-follow in the following ways:
  • There is no need to test if the values returned by org-ql-view--expand-buffers-files is a buffer or string at https://github.com/alphapapa/org-ql/blob/31aeb0a2505acf8044c07824888ddec7f3e529c1/org-ql-view.el#L636 This will reflect in the test cases as well

[alphapapa]

Thanks. If we agree in #258 to require buffer arguments to be buffer objects rather than buffer names, that should simplify these changes a bit.

[dmgerman]

It would be great to have this feature.

I was looking at this function today. I wish there was a way to abstract this list into a variable:

      (list 'buffer 'org-agenda-files 'org-directory 'all)

so one can add another list to it, either by providing a function or by an explicit list. From my experiments it is not as trivial as simply refactoring the variable.

[ahmed-shariff]

We tried to solve it in #228 , didn't have the time to finish that. There were a few issues we hand't ironed out. I can revisit this when I have some time.