Treesitter configuration - Snehil's Neovim Configuration

Treesitter provides superior syntax highlighting and code understanding through parsing, enabling intelligent text objects and navigation.

Core plugins

The Treesitter setup includes three main plugins:

nvim-treesitter

Core parser and highlighting engine

textobjects

Code-aware text objects and motions

context

Sticky context header showing scope

Installation

Treesitter is loaded immediately (not lazy) and automatically updates parsers:

lua/plugins/treesitter.lua

{
  "nvim-treesitter/nvim-treesitter",
  branch = "main",
  lazy = false,
  build = ":TSUpdate",
  opts = {},
}

The :TSUpdate command runs automatically after installation to compile all parsers.

Language support

Parsers are automatically installed for these languages:

lua/plugins/treesitter.lua

ensure_installed = {
  "c",
  "lua",
  "vim",
  "vimdoc",
  "query",
  "markdown",
  "markdown_inline",
  "go",
  "gomod",
  "gosum",
  "jsdoc",
  "javascript",
  "typescript",
  "tsx",
  "angular",
  "html",
}

Auto-installation

lua/plugins/treesitter.lua

auto_install = true,

Parsers for other languages are installed automatically when you open a file of that type.

Syntax highlighting

Treesitter highlighting is enabled with performance optimizations:

lua/plugins/treesitter.lua

highlight = {
  enable = true,
  
  disable = function(lang, buf)
    -- Disable for large files (>100KB)
    if not buf or type(buf) ~= "number" then
      return false
    end
    local max_filesize = 100 * 1024 -- 100 KB
    local ok, stats = pcall(vim.uv.fs_stat, vim.api.nvim_buf_get_name(buf))
    if ok and stats and stats.size > max_filesize then
      return true
    end
  end,
  
  additional_vim_regex_highlighting = false,
}

Treesitter highlighting is automatically disabled for files larger than 100KB to maintain performance.

Text objects

Treesitter text objects allow you to operate on semantic code units like functions, classes, and arguments.

Selecting text objects

Operator	Target	Description
`af`	Function (outer)	Around function including signature
`if`	Function (inner)	Inside function body only
`ac`	Class (outer)	Around class including declaration
`ic`	Class (inner)	Inside class body
`aa`	Argument (outer)	Around parameter/argument
`ia`	Argument (inner)	Inside argument (value only)
`ao`	Loop (outer)	Around loop statement
`io`	Loop (inner)	Inside loop body
`ai`	Conditional (outer)	Around if/else/switch
`ii`	Conditional (inner)	Inside conditional body
`ar`	Return (outer)	Around return statement
`ir`	Return (inner)	Return value only
`as`	Scope	Around local scope

Usage examples

Visual selection
Deletion
Yanking

vif - Select inside function body
vac - Select around class
vaa - Select around argument

daf - Delete entire function
daa - Delete argument (including comma)
dic - Delete class body

yif - Yank function body
yac - Yank entire class
yar - Yank return statement

Configuration

lua/plugins/treesitter.lua

require("nvim-treesitter-textobjects").setup({
  select = {
    lookahead = true,
    selection_modes = {
      ["@parameter.outer"] = "v", -- character-wise for parameters
      ["@function.outer"] = "V", -- line-wise for functions
    },
    include_surrounding_whitespace = false,
  },
})

Lookahead allows you to target the next text object even if your cursor isn’t directly on it.

Jump between semantic code elements:

Key	Action	Description
`]f`	Next function start	Jump to start of next function
`]F`	Next function end	Jump to end of next function
`[f`	Prev function start	Jump to start of previous function
`[F`	Prev function end	Jump to end of previous function

Key	Action	Description
`]c`	Next class start	Jump to start of next class
`]C`	Next class end	Jump to end of next class
`[c`	Prev class start	Jump to start of previous class
`[C`	Prev class end	Jump to end of previous class

Key	Action	Description
`]o`	Next loop	Jump to next loop
`[o`	Prev loop	Jump to previous loop
`]i`	Next conditional	Jump to next if/else/switch
`[i`	Prev conditional	Jump to previous conditional

Swapping

Swap function arguments/parameters:

Key	Action	Description
`<leader>a`	Swap next	Swap with next parameter
`<leader>A`	Swap previous	Swap with previous parameter

lua/plugins/treesitter.lua

map("n", "<leader>a", function()
  swap.swap_next("@parameter.inner")
end, { desc = "Swap next parameter" })

Example

function example(first, second, third) {
  // With cursor on 'second':
  // <leader>a swaps to: function example(first, third, second)
  // <leader>A swaps to: function example(second, first, third)
}

Treesitter context

Shows the current function/class/scope at the top of the window when scrolling:

lua/plugins/treesitter.lua

{
  "nvim-treesitter/nvim-treesitter-context",
  dependencies = { "nvim-treesitter/nvim-treesitter" },
  opts = {
    enable = true,
    max_lines = 4, -- Show up to 4 lines of context
    min_window_height = 15, -- Only show when window is tall enough
    line_numbers = true,
    multiline_threshold = 20, -- Show for scopes with 20+ lines
    trim_scope = "outer",
    mode = "topline",
    separator = "─",
    zindex = 20,
  },
}

Sticky header

Function/class signature stays visible while scrolling

Performance optimized

Disabled for files over 200KB

Visual separator

Clear horizontal line separates context from content

Smart activation

Only shows for scopes with 20+ lines

Context example

When scrolling inside a long function:

──────────────────────────────────────────────
  42 | function processUserData(data) {
──────────────────────────────────────────────
  68 |   // Current line visible here
  69 |   return result;

Indentation

Treesitter-based indentation:

lua/plugins/treesitter.lua

indent = {
  enable = true,
}

Provides better indentation for complex expressions and nested structures.

Incremental selection

Expand selection based on syntax tree:

Key	Action	Description
`<leader>ss`	Init selection	Start incremental selection
`<leader>si`	Increment node	Expand to parent node
`<leader>sc`	Increment scope	Expand to scope
`<leader>sn`	Decrement node	Shrink to child node

lua/plugins/treesitter.lua

incremental_selection = {
  enable = true,
  keymaps = {
    init_selection = "<leader>ss",
    node_incremental = "<leader>si",
    scope_incremental = "<leader>sc",
    node_decremental = "<leader>sn",
  },
}

Example workflow

Start selection

Press <leader>ss with cursor on a variable name Selects: variable

Expand once

Press <leader>si Selects: variable.property

Expand again

Press <leader>si Selects: const x = variable.property

Expand to scope

Press <leader>sc Selects: entire function body

Treesitter modules

The configuration uses treesitter-modules.nvim for better module organization:

lua/plugins/treesitter.lua

{
  "MeanderingProgrammer/treesitter-modules.nvim",
  dependencies = { "nvim-treesitter/nvim-treesitter" },
  opts = { ... },
}

This provides the same configuration interface as the official plugin but with improved stability.

Commands

:TSInstall <language>

Install parser for specific language:

:TSInstall python
:TSInstall rust

:TSUpdate

Update all installed parsers:

:TSUpdate

:TSModuleInfo

Show status of all Treesitter modules:

:TSModuleInfo

:InspectTree

Open Treesitter syntax tree inspector:

:InspectTree

Shows the parsed syntax tree for current buffer.

Toggle Treesitter

Disable/enable Treesitter highlighting:

<leader>uT

This toggle is provided by Snacks.nvim.

Performance tips

Large files

Automatically disabled for files over 100KB

Context

Context disabled for files over 200KB

Minimal highlighting

No additional vim regex highlighting

Selective context

Context only shows for scopes with 20+ lines

nvim-ts-autotag: Auto-close HTML/JSX tags (see Editing plugins)
nvim-ts-context-commentstring: Context-aware comments (see Editing plugins)
Blink.cmp: Uses Treesitter for smarter completions (see Completions)

Get Started

Core Configuration

Language Support

Plugin Guide

Customization

​Core plugins

nvim-treesitter

textobjects

context

​Installation

​Language support

​Auto-installation

​Syntax highlighting

​Text objects

​Selecting text objects

​Usage examples

​Configuration

​Navigation

​Function navigation

​Class navigation

​Loop and conditional navigation

​Swapping

​Example

​Treesitter context

Sticky header

Performance optimized

Visual separator

Smart activation

​Context example

​Indentation

​Incremental selection

​Example workflow

​Treesitter modules

​Commands

​Toggle Treesitter

​Performance tips

Large files

Context

Minimal highlighting

Selective context

​Related plugins

Build docs developers (and LLMs) love

Core plugins

Installation

Language support

Auto-installation

Syntax highlighting

Text objects

Selecting text objects

Usage examples

Configuration

Navigation

Function navigation

Class navigation

Loop and conditional navigation

Swapping

Example

Treesitter context

Context example

Indentation

Incremental selection

Example workflow

Treesitter modules

Commands

Toggle Treesitter

Performance tips

Related plugins