feat: add formatter config option to change name of temporary file (#332

)

README.md

@@ -464,6 +464,8 @@ require("conform").setup({
       cwd = require("conform.util").root_file({ ".editorconfig", "package.json" }),
       -- When cwd is not found, don't run the formatter (default false)
       require_cwd = true,
+      -- When stdin=false, use this template to generate the temporary file that gets formatted
+      tmpfile_format = ".conform.$RANDOM.$FILENAME",
       -- When returns false, the formatter will not be used
       condition = function(ctx)
         return vim.fs.basename(ctx.filename) ~= "README.md"

doc/conform.txt

@@ -72,6 +72,8 @@ OPTIONS                                                          *conform-option
           cwd = require("conform.util").root_file({ ".editorconfig", "package.json" }),
           -- When cwd is not found, don't run the formatter (default false)
           require_cwd = true,
+          -- When stdin=false, use this template to generate the temporary file that gets formatted
+          tmpfile_format = ".conform.$RANDOM.$FILENAME",
           -- When returns false, the formatter will not be used
           condition = function(ctx)
             return vim.fs.basename(ctx.filename) ~= "README.md"

lua/conform/init.lua

@@ -14,6 +14,7 @@ local M = {}
 ---@field cwd? fun(self: conform.JobFormatterConfig, ctx: conform.Context): nil|string
 ---@field require_cwd? boolean When cwd is not found, don't run the formatter (default false)
 ---@field stdin? boolean Send buffer contents to stdin (default true)
+---@field tmpfile_format? string When stdin=false, use this format for temporary files (default ".conform.$RANDOM.$FILENAME")
 ---@field condition? fun(self: conform.JobFormatterConfig, ctx: conform.Context): boolean
 ---@field exit_codes? integer[] Exit codes that indicate success (default {0})
 ---@field env? table<string, any>|fun(self: conform.JobFormatterConfig, ctx: conform.Context): table<string, any>

lua/conform/runner.lua

@@ -442,8 +442,13 @@ M.build_context = function(bufnr, config, range)
   end
 
   if not config.stdin then
+    local template = config.tmpfile_format
+    if not template then
+      template = ".conform.$RANDOM.$FILENAME"
+    end
     local basename = vim.fs.basename(filename)
-    local tmpname = string.format(".conform.%d.%s", math.random(1000000, 9999999), basename)
+    local tmpname =
+      template:gsub("$FILENAME", basename):gsub("$RANDOM", tostring(math.random(1000000, 9999999)))
     local parent = vim.fs.dirname(filename)
     filename = fs.join(parent, tmpname)
   end

scripts/options_doc.lua

@@ -59,6 +59,8 @@ require("conform").setup({
       cwd = require("conform.util").root_file({ ".editorconfig", "package.json" }),
       -- When cwd is not found, don't run the formatter (default false)
       require_cwd = true,
+      -- When stdin=false, use this template to generate the temporary file that gets formatted
+      tmpfile_format = ".conform.$RANDOM.$FILENAME",
       -- When returns false, the formatter will not be used
       condition = function(ctx)
         return vim.fs.basename(ctx.filename) ~= "README.md"