feat(nix): add Nix language support for nested scope detection

lua/hlchunk/mods/chunk/chunk_conf.lua

@@ -7,6 +7,7 @@ local BaseConf = require("hlchunk.mods.base_mod.base_conf")
 ---@field textobject? string
 ---@field max_file_size? number
 ---@field error_sign? boolean
+---@field node_type_styles? table<string, table> mapping of node type patterns to style
 
 ---@class HlChunk.ChunkConf : HlChunk.BaseConf
 ---@field use_treesitter boolean
@@ -16,6 +17,7 @@ local BaseConf = require("hlchunk.mods.base_mod.base_conf")
 ---@field error_sign boolean
 ---@field duration number
 ---@field delay number
+---@field node_type_styles table<string, table> mapping of node type patterns to style
 ---@overload fun(conf?: table): HlChunk.ChunkConf
 local ChunkConf = class(BaseConf, function(self, conf)
     local default_conf = {
@@ -38,6 +40,21 @@ local ChunkConf = class(BaseConf, function(self, conf)
         error_sign = true,
         duration = 200,
         delay = 300,
+        -- Node type to style mapping (patterns matched against treesitter node type)
+        -- If a node type matches multiple patterns, first match wins
+        -- If no match, falls back to default style[1]
+        node_type_styles = {
+            -- Example config (users can override):
+            -- ["^func"] = { fg = "#99aee5" },      -- functions: blue
+            -- ["^if"] = { fg = "#c2a2e3" },        -- conditionals: purple
+            -- ["else"] = { fg = "#c2a2e3" },       -- else: purple
+            -- ["^for"] = { fg = "#fbdf90" },       -- for loops: yellow
+            -- ["^while"] = { fg = "#fbdf90" },     -- while loops: yellow
+            -- ["try"] = { fg = "#9fe8c3" },        -- try/catch: green
+            -- ["except"] = { fg = "#9fe8c3" },     -- except: green
+            -- ["catch"] = { fg = "#9fe8c3" },      -- catch: green
+            -- ["class"] = { fg = "#ef8891" },      -- classes: red
+        },
     }
     conf = vim.tbl_deep_extend("force", default_conf, conf or {}) --[[@as HlChunk.ChunkConf]]
     BaseConf.init(self, conf)
@@ -50,6 +67,7 @@ local ChunkConf = class(BaseConf, function(self, conf)
     self.error_sign = conf.error_sign
     self.duration = conf.duration
     self.delay = conf.delay
+    self.node_type_styles = conf.node_type_styles
 end)
 
 return ChunkConf

lua/hlchunk/mods/chunk/init.lua

@@ -17,6 +17,9 @@ local rangeFromTo = chunkHelper.rangeFromTo
 local utf8Split = chunkHelper.utf8Split
 local shallowCmp = chunkHelper.shallowCmp
 
+-- Counter for dynamically created highlight groups
+local hl_group_counter = 0
+
 ---@class HlChunk.ChunkMetaInfo : HlChunk.MetaInfo
 ---@field task HlChunk.LoopTask | nil
 ---@field pre_virt_text_list string[]
@@ -121,6 +124,37 @@ function ChunkMod:get_chunk_data(range, virt_text_list, row_list, virt_text_win_
     end
 end
 
+--- Get the highlight group for a given node type
+--- Matches node_type against patterns in node_type_styles config
+---@param node_type string|nil the treesitter node type
+---@param is_error boolean whether the chunk has an error
+---@return string highlight group name
+function ChunkMod:get_hl_group_for_node_type(node_type, is_error)
+    -- If error, always use error style
+    if is_error then
+        return "HLChunk2"
+    end
+
+    -- If no node type or no node_type_styles configured, use default
+    if not node_type or not self.conf.node_type_styles or vim.tbl_isempty(self.conf.node_type_styles) then
+        return "HLChunk1"
+    end
+
+    -- Try to match node_type against configured patterns
+    for pattern, style in pairs(self.conf.node_type_styles) do
+        if node_type:find(pattern) then
+            -- Create a dynamic highlight group for this style
+            hl_group_counter = hl_group_counter + 1
+            local hl_name = "HLChunkNodeType" .. hl_group_counter
+            api.nvim_set_hl(0, hl_name, style)
+            return hl_name
+        end
+    end
+
+    -- No match, use default
+    return "HLChunk1"
+end
+
 function ChunkMod:render(range, opts)
     opts = opts or { error = false, lazy = false }
     if not self:shouldRender(range.bufnr) then
@@ -148,10 +182,12 @@ function ChunkMod:render(range, opts)
 
     local row_opts = {
         virt_text_pos = "overlay",
+        virt_text_repeat_linebreak = true,
         hl_mode = "combine",
         priority = 100,
     }
-    local text_hl = opts.error and "HLChunk2" or "HLChunk1"
+    -- Get highlight based on node type (or error/default)
+    local text_hl = self:get_hl_group_for_node_type(range.node_type, opts.error)
     if self.conf.delay == 0 or opts.lazy == false then
         for i, vt in ipairs(virt_text_list) do
             row_opts.virt_text = { { vt, text_hl } }

lua/hlchunk/utils/chunkHelper.lua

@@ -80,15 +80,15 @@ local function get_chunk_range_by_treesitter(pos)
         local node_start, _, node_end, _ = cursor_node:range()
         if node_start ~= node_end and is_suit_type(node_type) then
             return cursor_node:has_error() and chunkHelper.CHUNK_RANGE_RET.CHUNK_ERR or chunkHelper.CHUNK_RANGE_RET.OK,
-                Scope(pos.bufnr, node_start, node_end)
+                Scope(pos.bufnr, node_start, node_end, node_type)
         end
         local parent_node = cursor_node:parent()
         if parent_node == cursor_node then
             break
         end
         cursor_node = parent_node
     end
-    return chunkHelper.CHUNK_RANGE_RET.NO_CHUNK, Scope(pos.bufnr, -1, -1)
+    return chunkHelper.CHUNK_RANGE_RET.NO_CHUNK, Scope(pos.bufnr, -1, -1, nil)
 end
 
 ---@param opts? {pos: HlChunk.Pos, use_treesitter: boolean}

lua/hlchunk/utils/scope.lua

@@ -2,14 +2,16 @@
 ---@field bufnr number
 ---@field start number
 ---@field finish number
----@overload fun(bufnr: number, start: number, finish: number): HlChunk.Scope
+---@field node_type? string treesitter node type (e.g., "function", "if_statement", "for_loop")
+---@overload fun(bufnr: number, start: number, finish: number, node_type?: string): HlChunk.Scope
 ---0-indexing, include start and finish
 -- local Scope = class(constructor)
-local function Scope(bufnr, start, finish)
+local function Scope(bufnr, start, finish, node_type)
     return {
         bufnr = bufnr,
         start = start,
         finish = finish,
+        node_type = node_type,
     }
 end
 

lua/hlchunk/utils/ts_node_type/init.lua

@@ -3,6 +3,7 @@ local M = {}
 M.cpp = require("hlchunk.utils.ts_node_type.cpp")
 M.css = require("hlchunk.utils.ts_node_type.css")
 M.lua = require("hlchunk.utils.ts_node_type.lua")
+M.nix = require("hlchunk.utils.ts_node_type.nix")
 M.rust = require("hlchunk.utils.ts_node_type.rust")
 M.yaml = require("hlchunk.utils.ts_node_type.yaml")
 M.zig = require("hlchunk.utils.ts_node_type.zig")

lua/hlchunk/utils/ts_node_type/nix.lua

@@ -0,0 +1,17 @@
+-- Nix-specific treesitter node types for hlchunk
+-- Covers: let expressions, attribute sets, lambda functions, with expressions, etc.
+-- Format: node_type = true (table with keys, not array)
+return {
+    let_expression = true,          -- let ... in ...
+    attrset_expression = true,      -- { ... }
+    rec_attrset_expression = true,  -- rec { ... }
+    list_expression = true,         -- [ ... ]
+    lambda_expression = true,       -- arg: body
+    function_expression = true,     -- { args }: body  
+    with_expression = true,         -- with ...; ...
+    if_expression = true,           -- if ... then ... else ...
+    assert_expression = true,       -- assert ...; ...
+    binding = true,                 -- name = value;
+    inherit = true,                 -- inherit ...;
+    inherit_from = true,            -- inherit (...) ...;
+}