Buffers rework (indicators and sorting)

[Conni2461]

Close #179
Close #245

This is currently WIP. Basically it is hacked together.

This reworks builtin.buffers, so that we also display the indicators.
I'm currently parsing the output of :buffers. I'm not sure if i can get the indicators on another way.
This currently shows all buffer, also unloaded buffers. (So show_all_buffers = true does nothing)(Should now work as before)

This also adds a function, which could help us display outputs in a more table like format, like suggested in #118.
This does not change the other builtins to be to a table format. (I plan to do this in another pr).

I also briefly looked into #179 and i think we can use unpack(vim.fn.getbufinfo(tonumber(bufnr))).lastused to sort the buffers list. (I think this should be configurable. either pick the current solution or based on lastused.). I might do this in this PR aswell. If I can figure out how the whole sorting part works.
Previous Buffer is default selection. Should be configurable. Configurable with sort_lastused = true

Before PR	New

@sunjon Would be great if you could comment the new layout(display output with the indicators).
Currently does not handle readonly buffers.
If no buffer has a write indicator the column will not be printed.

@Stanislav-Lapata and @sunjon when i sort the buffers after lastused, do you want the active buffer be displayed or should we filter out the current one?

[Stanislav-Lapata]

@Conni2461
I think current buffer should be displayed but it should be disabled
Active line should be previous buffer

[Conni2461]

@Conni2461
I think current buffer should be displayed but it should be disabled
Active line should be previous buffer

Thanks that made it clearer for me.
I'm still not sure what you mean with disable current buffer. Do you mean this buffer can't be selected at all? Because i can't really image how the workflow would be if a buffer in the middle of a big list is disabled.

I got the other think working(active line should be previous buffer), but i think @tjdevries would not be happy with this code. It's currently pretty hacky and i think it should only work with sorting_strategy = 'descending'.

But could you test it anyway @Stanislav-Lapata?

I would clean up the code tomorrow, @tjdevries.

[Stanislav-Lapata]

@Conni2461
I described fzf.vim logic
Install fzf.vim if you are comfortable.

Plug 'junegunn/fzf', { 'dir': '~/.fzf', 'do': './install --bin' }
Plug 'junegunn/fzf.vim'

And run :Buffer

You shouldn't repeat fzf.vim logic fully. I would just do sorting for a start and show all buffers without disabling current buffer.

Sorry for my English

[Conni2461]

@Stanislav-Lapata
I haven't used fzf in a while. Okay i tested fzf and made some changes. I think this is more like fzf.
Could you try it out by running :lua require'telescope.builtin'.buffers{ show_all_buffers = true } and report back.
The selection of the current buffer is still possible and i think implementing a disable could be quiet tricky.

Both sorting_strategy should work now.

[Stanislav-Lapata]

@Conni2461
Looks nice. Thank you 👍

[tjdevries]

@Conni2461 I will probably take some of the code you have there for making a display table and do something very similar and then you can rebase this branch off of it at some point.

I will take a look at the other parts, particularly the selection strategy stuff, later. If you want to submit a separate PR for the selection strategy fixes, I will definitely take a look. Thanks!

[Conni2461]

The selection_strategy fix for row and follow is in #218.
I will continue to work on this one in the next couple of days. Have to do other stuff first 😆.
Thanks for picking up my display table stuff. I took a brief look at it and it looks good.

[Conni2461]

@tjdevries Should be good to review. If you find some time.

[tjdevries]

does calling bufload do this?

[Conni2461]

yes i think so. I have highlighting for unloaded buffers and it seems like for loaded buffers i don't have to do anything

[tjdevries]

What's left for this PR?

[Conni2461]

Basically i also added @sunjon wish to view unnamed buffers but i haven't figured out a way to open them.
:e #nr will result in Vim(edit):E499: Empty file name for '%' or '#', only works with ":p:h", so is my only option vim.api.nvim_win_set_buf(winnr, unnamed_bufnr)? Besides that i think done
Have figured it out. show_all_buffers = true should also show unnamed buffers now

[Conni2461]

@tjdevries Should be done from my side. You can take a look at this.