fix.nvim

A Neovim plugin for viewing FIX protocol messages

Features

• Syntax highlighting for FIX messages (via tree-sitter-fix)
• Tag and value annotation with virtual text
• Easy navigation between fields and messages
• Support for multiple FIX versions
• SOH (\x01) character concealing for readability
• Field picker (optional, with snacks.nvim)

Screenshots

Installation

lazy.nvim

{
  "sergluka/fix.nvim",
  dependencies = {
    "manoelcampos/xml2lua",
    "ColinKennedy/mega.cmdparse",
    "ColinKennedy/mega.logging",
    "folke/snacks.nvim", -- optional, for the fields picker
  },
  opts = {
    -- Configuration options here
  },
  build = ":TSUpdate fix",
}

Usage

Command	Lua API	Description
:FIX --help		Show help
:FIX annotations [all, tag, value, message]	require("fix").annotate(scope)	Toggle annotations
:FIX picker	require("fix.snacks").open()	Show fields picker
:FIX browse	require("fix").browse_tag_online()	Open Onixs tag info page in browser
:FIX yank field [--reg=<REGISTER>]	require("fix").yank_field(reg)	Yank annotated field under cursor
:FIX yank message [--reg=<REGISTER>]	require("fix").yank_message(reg)	Yank annotated message under cursor

Configuration

{
  -- Filetype detection rules (see `vim.filetype.add.filetypes`)
  ft = {
    extensions = { "fix", "fixlog" },
    pattern = { ".*%.fix.txt" },
  },
  annotate = {
    -- Tag annotation
    tag = {
      enabled = true,
      formatter = require("fix.formatters.tag").default,
    },
    -- Value annotation
    value = {
      enabled = true,
      formatter = require("fix.formatters.value").default,
    },
    -- Message (title) annotation
    message = {
      enabled = true,
      position = "above", -- "above" | "below"
      formatter = require("fix.formatters.message").default,
    },
  },
}

Keybindings

No keybindings are set by default. Example mappings (add to ftplugin/fix.lua or your config):

local fix = require("fix")

vim.keymap.set("n", "<localleader>t", function() fix.annotate_toggle("message") end, { desc = "fix: toggle message annotation", buffer = true })
vim.keymap.set("n", "<localleader>T", function() fix.annotate_toggle("all") end, { desc = "fix: toggle all annotation", buffer = true })
vim.keymap.set("n", "<localleader>x", function() fix.browse_tag_online() end, { desc = "fix: open online doc", buffer = true })
vim.keymap.set("n", "<localleader>yf", function() fix.yank_field("+") end, { desc = "fix: yank field", buffer = true })
vim.keymap.set("n", "<localleader>yy", function() fix.yank_message("+") end, { desc = "fix: yank message", buffer = true })
vim.keymap.set("n", "<localleader><localleader>", function() require("fix.snacks").open() end, { desc = "fix: browse tags", buffer = true })

local ts_move = require("nvim-treesitter.textobjects.move")

vim.keymap.set({ "n", "v" }, "]]", function() ts_move.goto_next_start("@field") end, { desc = "fix: next field start", buffer = true })
vim.keymap.set({ "n", "v" }, "[[", function() ts_move.goto_previous_start("@field") end, { desc = "fix: previous field start", buffer = true })
vim.keymap.set({ "n", "v" }, "]}", function() ts_move.goto_next_end("@field") end, { desc = "fix: next field end", buffer = true })
vim.keymap.set({ "n", "v" }, "[{", function() ts_move.goto_previous_end("@field") end, { desc = "fix: previous field end", buffer = true })

vim.keymap.set({ "n", "v" }, "]m", function() ts_move.goto_next_start("@message") end, { desc = "fix: next message start", buffer = true })
vim.keymap.set({ "n", "v" }, "[m", function() ts_move.goto_previous_start("@message") end, { desc = "fix: previous message start", buffer = true })
vim.keymap.set({ "n", "v" }, "]M", function() ts_move.goto_next_end("@message") end, { desc = "fix: next message end", buffer = true })
vim.keymap.set({ "n", "v" }, "[M", function() ts_move.goto_previous_end("@message") end, { desc = "fix: previous message end", buffer = true })

vim.keymap.set({ "n", "v" }, "]g", function() ts_move.goto_next_start("@comment") end, { desc = "fix: next comment start", buffer = true })
vim.keymap.set({ "n", "v" }, "[g", function() ts_move.goto_previous_start("@comment") end, { desc = "fix: previous comment start", buffer = true })
vim.keymap.set({ "n", "v" }, "]G", function() ts_move.goto_next_end("@comment") end, { desc = "fix: next comment end", buffer = true })
vim.keymap.set({ "n", "v" }, "[G", function() ts_move.goto_previous_end("@comment") end, { desc = "fix: previous comment end", buffer = true })

Limitations

• For now plugin supports tree-sitter master branch only

• Due to a Neovim limitation, virtual text above the first line is not displayed, so the first message title may not be visible. Workarounds:

  • Add an empty line at the beginning of the file
  • Press C-b to scroll to the top after opening
  • Use annotate.message.position = "below" to display the message title below the message

Links

• tree-sitter-fix parser
• FIX repository