feat: allow running commands in a shell (#49)

2 files changed, 18 insertions, 11 deletions

diff --git a/lua/conform/init.lua b/lua/conform/init.lua
index ff30686..a19813e 100644
--- a/lua/conform/init.lua
+++ b/lua/conform/init.lua
@@ -9,8 +9,8 @@ local M = {}
 
 ---@class (exact) conform.FormatterConfig
 ---@field command string|fun(ctx: conform.Context): string
----@field args? string[]|fun(ctx: conform.Context): string[]
----@field range_args? fun(ctx: conform.RangeContext): string[]
+---@field args? string|string[]|fun(ctx: conform.Context): string|string[]
+---@field range_args? fun(ctx: conform.RangeContext): string|string[]
 ---@field cwd? fun(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)
diff --git a/lua/conform/runner.lua b/lua/conform/runner.lua
index ff8fbef..fff638b 100644
--- a/lua/conform/runner.lua
+++ b/lua/conform/runner.lua
@@ -48,12 +48,13 @@ end
 
 ---@param ctx conform.Context
 ---@param config conform.FormatterConfig
+---@return string|string[]
 M.build_cmd = function(ctx, config)
   local command = config.command
   if type(command) == "function" then
     command = command(ctx)
   end
-  local cmd = { command }
+  ---@type string|string[]
   local args = {}
   if ctx.range and config.range_args then
     ---@cast ctx conform.RangeContext
@@ -67,16 +68,22 @@ M.build_cmd = function(ctx, config)
     end
   end
 
-  ---@diagnostic disable-next-line: param-type-mismatch
-  for _, v in ipairs(args) do
-    if v == "$FILENAME" then
-      v = ctx.filename
-    elseif v == "$DIRNAME" then
-      v = ctx.dirname
+  if type(args) == "string" then
+    local interpolated = args:gsub("$FILENAME", ctx.filename):gsub("$DIRNAME", ctx.dirname)
+    return command .. " " .. interpolated
+  else
+    local cmd = { command }
+    ---@diagnostic disable-next-line: param-type-mismatch
+    for _, v in ipairs(args) do
+      if v == "$FILENAME" then
+        v = ctx.filename
+      elseif v == "$DIRNAME" then
+        v = ctx.dirname
+      end
+      table.insert(cmd, v)
     end
-    table.insert(cmd, v)
+    return cmd
   end
-  return cmd
 end
 
 ---@param range? conform.Range