How does highlighting work?

[anuvyklack]

How do highlighting groups are set?

The pending item highlight properties are somehow set to yellow and italic:

The TSplaygroud shows the next

my concealer module settings are:

pending = {                                                                     
   enabled = true,                                                              
   icon = "",                                                                  
   highlight = "NeorgTodoItemPendingMark",                                      
   query = "(todo_item_pending) @icon",                                         
   extract = function() return 1 end,                                           
},                                                                              

But I cannot find any mentions about NeorgTodoItemPendingMark or NeorgTodoItemPending or NeorgTodoItem1Pending inside my colorsheme gruvbox-material code base or inside Neorg code base, except queries/norg/highlights.scm file. How dose Neovim deside which highlight properties to choose?

The second question is: what extract function do?

  extract = function() return 1 end,                                            

[vhyrro]

Hey! Before I answer the question about the highlight groups I do want to let you know that you only need to change the settings that you care about in the pending table - everything else will just be kept as the default. This means that you can refactor your code to:

pending = {                                                                                        
   icon = "",
},  

And not have to worry about all the magic like extract. That function basically tells Neorg how many characters it should offset by, in this case one, otherwise you would get: <icon>-] instead of [<icon>].

About the highlights though - Neorg uses core.integrations.treesitter to bind Neorg highlight groups to treesitter highlight groups to feel consistent across all colourschemes that support it. To view every highlight enter a .norg file and run :filter Neorg highlight - this'll show you all the hl groups and what Neorg binds them to. To view a single highlight you can run :hi NeorgTodoItem1Pending, which for me shows that it binds to TSNamespace.

These can be changed in two ways. The first is to simply go somewhere in your config and

	vim.cmd([[
		hi link NeorgTodoItem1Pending MyPreferredHighlightGroup
	]])

Neorg will recognize that you've set the highlight group manually and won't touch it.

You can also customize core.integrations.treesitter directly, like so:

["core.integrations.treesitter"] = {
	config = {
		highlights = {
			-- all highlights go here
		}
	}
}

To view the entire table of highlight groups, consult the wiki entry. It's currently not indented properly because of some limitations but that'll show you how highlight groups can be changed through the config table.

I hope that answers your question, but when in doubt do ask again! I'll try and help out whenever I can :)