feat(keys): you can now create buffer-local filetype keymaps by specifying `ft=`. Fixes #1076

README.md

@@ -147,6 +147,7 @@ can be a `LazyKeys` table with the following key-value pairs:
 - **[1]**: (`string`) lhs **_(required)_**
 - **[2]**: (`string|fun()`) rhs **_(optional)_**
 - **mode**: (`string|string[]`) mode **_(optional, defaults to `"n"`)_**
+- **ft**: (`string|string[]`) `filetype` for buffer-local keymaps **_(optional)_**
 - any other option valid for `vim.keymap.set`
 
 Key mappings will load the plugin the first time they get executed.

lua/lazy/core/handler/keys.lua

@@ -9,6 +9,7 @@ local Loader = require("lazy.core.loader")
 ---@field noremap? boolean
 ---@field remap? boolean
 ---@field expr? boolean
+---@field ft? string|string[]
 ---@field id string
 
 ---@class LazyKeysHandler:LazyHandler
@@ -53,7 +54,7 @@ end
 function M.opts(keys)
   local opts = {}
   for k, v in pairs(keys) do
-    if type(k) ~= "number" and k ~= "mode" and k ~= "id" then
+    if type(k) ~= "number" and k ~= "mode" and k ~= "id" and k ~= "ft" then
       opts[k] = v
     end
   end
@@ -64,16 +65,21 @@ end
 function M:_add(keys)
   local lhs = keys[1]
   local opts = M.opts(keys)
+
+  ---@param buf? number
+  local function add(buf)
     vim.keymap.set(keys.mode, lhs, function()
       local plugins = self.active[keys.id]
 
       -- always delete the mapping immediately to prevent recursive mappings
-    self:_del(keys)
+      self:_del(keys, buf)
       self.active[keys.id] = nil
 
+      if plugins then
         Util.track({ keys = lhs })
         Loader.load(plugins, { keys = lhs })
         Util.track()
+      end
 
       local feed = vim.api.nvim_replace_termcodes("<Ignore>" .. lhs, true, true, true)
       -- insert instead of append the lhs
@@ -83,14 +89,38 @@ function M:_add(keys)
       nowait = opts.nowait,
       -- we do not return anything, but this is still needed to make operator pending mappings work
       expr = true,
+      buffer = buf,
     })
   end
 
----@param keys LazyKeys
-function M:_del(keys)
-  pcall(vim.keymap.del, keys.mode, keys[1])
+  if keys.ft then
+    vim.api.nvim_create_autocmd("FileType", {
+      pattern = keys.ft,
+      callback = function(event)
+        if self.active[keys.id] then
+          add(event.buf)
+        else
+          -- Only create the mapping if its managed by lazy
+          -- otherwise the plugin is supposed to manage it
           if keys[2] then
-    vim.keymap.set(keys.mode, keys[1], keys[2], M.opts(keys))
+            self:_del(keys, event.buf)
+          end
+        end
+      end,
+    })
+  else
+    add()
+  end
+end
+
+---@param keys LazyKeys
+---@param buf number?
+function M:_del(keys, buf)
+  pcall(vim.keymap.del, keys.mode, keys[1], { buffer = buf })
+  if keys[2] then
+    local opts = M.opts(keys)
+    opts.buffer = buf
+    vim.keymap.set(keys.mode, keys[1], keys[2], opts)
   end
 end