format-order.nvim

Restore "order" to the format

About

This plugin is intended to integrate conform.nvim and lsp formatting and allow you to write complex format settings in a simple, declarative way.

Install & Setup

This is config example for lazy.nvim. This plugin does nothing about format-on-save. You need to configure it using autocmd.

Also, unless you specify filetypes, this plugin does nothing. For detail, see Config section.

{
  {
    "nazo6/format-order.nvim",
    event = { "BufRead" },
    dependencies = {
      {
        "stevearc/conform.nvim",
        config = function()
          require("conform").setup {}
        end,
      },
    },
    config = function()
      require("fmo").setup {
        -- For detail, see Config section
        filetypes = {},
      }

      vim.api.nvim_create_autocmd({ "BufWritePre" }, {
        callback = function()
          require("fmo").format()
        end,
      })
    end,
  },
}

Config

It is difficult to fully describe in words how this plugin works, so here is example code and diagrams.

Example 1: Web

Setup for web development. For simplicity, only JavaScript is configured.

local formatters = {
  prettierd = {
    type = "conform",
    name = "prettierd",
    root_pattern = {
      -- omitted in this example
    },
  },
  deno_fmt = { type = "conform", name = "deno_fmt", root_pattern = { "deno.json", "deno.jsonc" } },
}

require("fmo").setup({
  filetypes = {
    javascript = {
      groups = {
        {
          specs = {
            { { type = "lsp", name = "denols" } },
            { { type = "lsp", name = "biome" } },
            {
              formatters.prettierd,
              formatters.deno_fmt,
            },
            { { type = "lsp", name = "vtsls" } },
          },
        },
      },
      default = formatters.deno_fmt,
    },
  },
})

And the diagram of the example is:

flowchart TD
    classDef eb fill:cyan
    s(["fmo.format()"])
    s --> ift{{Filetype is...}}
    ift -- Javascript --> group
    ift -- Other --> ii1{{fallback_lsp.no_ft is}}
    ii1 -- true --> fb[LSP format is executed] --> e
    ii1 -- false -->e
    subgraph group[ ]
    ii{{group.buf_condition returns false}}
    ii -- Yes --> e5
    ii -- No --> l:d
    l:d[LSP DenoLS]
    l:d -- No condition matched --> l:b[LSP Biome]
    l:d -- condition matched --> e1([Add formatter]):::eb
    l:b -- No condition matched --> ps1
    subgraph ps1[ ]
    c:p[Prettierd]
    c:df[deno_fmt]
    end    
    ps1 -- No condition matched --> l:v[LSP vtsls]
    ps1 -- At least one formatter condition matched --> e2([Formatter that has higher priority is added]):::eb
    l:v -- Condition matched --> e4([Add formatter]):::eb
    l:v -- Condition not matched --> e5([No formatters added])
    end
    group --> e6([Added formatters are executed]):::eb
    e6 --> e([end])

Config detail

The general flow is as explained above, but the details are described below.

Spec

Each formatter config table such as below is spec.

{
  type = "conform",
  name = "prettierd",
  root_pattern = {
    ".prettierrc",
    ".prettierrc.json",
    ".prettierrc.yml",
    ".prettierrc.yaml",
    ".prettierrc.json5",
    ".prettierrc.js",
    ".prettierrc.cjs",
    ".prettierrc.mjs",
    ".prettierrc.toml",
    "prettier.config.js",
    "prettier.config.cjs",
  },
}

Each spec must have type and name fields.

This plugin does not execute format by itself but relies on conform.nvim and nvim-lsp. So, type must be either conform or lsp.

name is the name of the formatter. In conform type, this must be conform formatter name. In lsp type, this is the name of the LSP server.

Other fields are described below.

Condition

Each formatter has a condition. If the condition is met, the formatter is added to the list of formatters to be executed. You can add condition with init_condition, buf_condition option.

If root_pattern and filetypes options are specified, they are automatically added to the buf_condition.

• init_condition is cached. It is executed only once.
• buf_condition is executed for each time format is executed.
• root_pattern is same as lspconfig's root_dir option. If not specified, always true.
• filetypes is a list of filetypes. If not specified, always true.

Also, in lsp type, unless lsp server is available, the condition is always false.

Priority

In the second layer of the spec group, the formatter with the highest priority is selected.

Currently, this plugin uses root_pattern to determine priority. The formatter that has deeper root has higher priority.