fix: enable_preview true

[MovieMaker93]

Description

This fix aims to resolve the issue about the "enable_preview" feature that wasn't working.
Now if you call:
:Telescope colorscheme enable_preview=true
while scrolling through the different color scheme options, the live preview is working (change color scheme accordingly)

Fixes #2966

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)

How Has This Been Tested?

Please describe the tests that you ran to verify your changes. Provide instructions so we can reproduce. Please also list relevant details about your configuration

I tried two different scenarios:

• :Telescope colorscheme enable_preview=true --> When scrolling through the different color schemes, the theme changes accordingly
• :Telescope colorscheme enable_preview=false --> When scrolling through the different color schemes, the theme doesn't change

Configuration:

• Neovim version (nvim --version): 0.9.4
• Operating system and version: ubuntu 22.04

Checklist:

• My code follows the style guidelines of this project (stylua)
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation (lua annotations)

[jamestrew]

I think the existing changes look good.
One thing I forgot to mention about that we should clean up is the existing code to set the previewer.

I think the if vim.fn.buflisted(bufnr) ~= 1 ... part of the code path was a prior attempt to enable previews without a previewer, but it either never worked or no longer works. So we can just completely remove this part. It should be redundant now either way. You can also probably remove the vim.cmd.colorscheme(entry.value) inside the define_preview function in the new_buffer_previewer block as well as it's also redundant now.

[MovieMaker93]

I think the existing changes look good. One thing I forgot to mention about that we should clean up is the existing code to set the previewer.

I think the if vim.fn.buflisted(bufnr) ~= 1 ... part of the code path was a prior attempt to enable previews without a previewer, but it either never worked or no longer works. So we can just completely remove this part. It should be redundant now either way. You can also probably remove the vim.cmd.colorscheme(entry.value) inside the define_preview function in the new_buffer_previewer block as well as it's also redundant now.

Okay, thanks for the feedback. I've removed both the vim.fn.buflisted check and the cmd.colorscheme command. In addition, just to be sure, I've tested it again, and it seems to work fine. Let me know if everything is correct on your end.

[jamestrew]

Thanks! Looks good and works for me as well.