fix: action mt so we can again concat actions from two different tables (#1143)

* fix: action mt so we can again concat actions from two different tables

- without actually changing the public interface
- without having a local table that keeps track of all actions

* this should clear actions now

we never actually called this function which is kinda a problem because
we never cleaned up previous mapping stores.
We can also make a better mappings store which has access to the keys
sequences which would help the showing actions part

* bugfix

* that should now clear everything

only tests left i think

* more tests

* cleanup

* hack: make sure all actions get cleared

lua/telescope/actions/mt.lua

@@ -14,7 +14,28 @@ local run_replace_or_original = function(replacements, original_func, ...)
   return original_func(...)
 end
 
-action_mt.create = function(mod)
+local append_action_copy = function(new, v, old)
+  table.insert(new, v)
+  new._func[v] = old._func[v]
+  new._static_pre[v] = old._static_pre[v]
+  new._pre[v] = old._pre[v]
+  new._replacements[v] = old._replacements[v]
+  new._static_post[v] = old._static_post[v]
+  new._post[v] = old._post[v]
+end
+
+--TODO(conni2461): Not a fan of this solution/hack. Needs to be addressed
+local all_mts = {}
+
+--- an action is metatable which allows replacement(prepend or append) of the function
+---@class Action
+---@field _func table<string, function>: the original action function
+---@field _static_pre table<string, function>: will allways run before the function even if its replaced
+---@field _pre table<string, function>: the functions that will run before the action
+---@field _replacements table<string, function>: the function that replaces this action
+---@field _static_post table<string, function>: will allways run after the function even if its replaced
+---@field _post table<string, function>: the functions that will run after the action
+action_mt.create = function()
   local mt = {
     __call = function(t, ...)
       local values = {}
@@ -27,7 +48,7 @@ action_mt.create = function(mod)
         end
 
         local result = {
-          run_replace_or_original(t._replacements[action_name], mod[action_name], ...),
+          run_replace_or_original(t._replacements[action_name], t._func[action_name], ...),
         }
         for _, res in ipairs(result) do
           table.insert(values, res)
@@ -45,18 +66,23 @@ action_mt.create = function(mod)
     end,
 
     __add = function(lhs, rhs)
-      local new_actions = {}
+      local new_action = setmetatable({}, action_mt.create())
       for _, v in ipairs(lhs) do
-        table.insert(new_actions, v)
+        append_action_copy(new_action, v, lhs)
       end
 
       for _, v in ipairs(rhs) do
-        table.insert(new_actions, v)
+        append_action_copy(new_action, v, rhs)
+      end
+      new_action.clear = function()
+        lhs.clear()
+        rhs.clear()
       end
 
-      return setmetatable(new_actions, getmetatable(lhs))
+      return new_action
     end,
 
+    _func = {},
     _static_pre = {},
     _pre = {},
     _replacements = {},
@@ -120,33 +146,47 @@ action_mt.create = function(mod)
     return self
   end
 
+  table.insert(all_mts, mt)
   return mt
 end
 
-action_mt.transform = function(k, mt, mod, v)
+action_mt.transform = function(k, mt, _, v)
   local res = setmetatable({ k }, mt)
   if type(v) == "table" then
     res._static_pre[k] = v.pre
     res._static_post[k] = v.post
-    mod[k] = v.action
+    res._func[k] = v.action
+  else
+    res._func[k] = v
   end
   return res
 end
 
 action_mt.transform_mod = function(mod)
-  local mt = action_mt.create(mod)
-
   -- Pass the metatable of the module if applicable.
   --    This allows for custom errors, lookups, etc.
   local redirect = setmetatable({}, getmetatable(mod) or {})
 
   for k, v in pairs(mod) do
-    redirect[k] = action_mt.transform(k, mt, mod, v)
+    local mt = action_mt.create()
+    redirect[k] = action_mt.transform(k, mt, _, v)
   end
 
-  redirect._clear = mt.clear
+  redirect._clear = function()
+    for k, v in pairs(redirect) do
+      if k ~= "_clear" then
+        pcall(v.clear)
+      end
+    end
+  end
 
   return redirect
 end
 
+action_mt.clear_all = function()
+  for _, v in ipairs(all_mts) do
+    pcall(v.clear)
+  end
+end
+
 return action_mt

lua/telescope/mappings.lua

@@ -221,10 +221,6 @@ mappings.apply_keymap = function(prompt_bufnr, attach_mappings, buffer_keymap)
       end
     end
   end
-
-  vim.cmd(
-    string.format([[autocmd BufDelete %s :lua require('telescope.mappings').clear(%s)]], prompt_bufnr, prompt_bufnr)
-  )
 end
 
 mappings.execute_keymap = function(prompt_bufnr, keymap_identifier)
@@ -237,6 +233,12 @@ mappings.execute_keymap = function(prompt_bufnr, keymap_identifier)
 end
 
 mappings.clear = function(prompt_bufnr)
+  require("telescope.actions.mt").clear_all()
+  -- TODO(conni2461): This seems like the better solution but it won't clear actions that were never mapped
+  -- for _, v in ipairs(keymap_store[prompt_bufnr]) do
+  --   pcall(v.clear)
+  -- end
+
   keymap_store[prompt_bufnr] = nil
 end
 

lua/telescope/pickers.lua

@@ -8,7 +8,6 @@ local channel = require("plenary.async.control").channel
 local popup = require "plenary.popup"
 
 local actions = require "telescope.actions"
-local action_set = require "telescope.actions.set"
 local config = require "telescope.config"
 local debounce = require "telescope.debounce"
 local deprecated = require "telescope.deprecated"
@@ -48,12 +47,6 @@ function Picker:new(opts)
     error "layout_strategy and get_window_options are not compatible keys"
   end
 
-  -- Reset actions for any replaced / enhanced actions.
-  -- TODO: Think about how we could remember to NOT have to do this...
-  --        I almost forgot once already, cause I'm not smart enough to always do it.
-  actions._clear()
-  action_set._clear()
-
   deprecated.options(opts)
 
   local layout_strategy = get_default(opts.layout_strategy, config.values.layout_strategy)
@@ -1304,6 +1297,7 @@ function pickers.on_close_prompt(prompt_bufnr)
   end
 
   picker.close_windows(status)
+  mappings.clear(prompt_bufnr)
 end
 
 function pickers.on_resize_window(prompt_bufnr)

lua/tests/automated/action_spec.lua

@@ -3,9 +3,7 @@ local action_set = require "telescope.actions.set"
 
 local transform_mod = require("telescope.actions.mt").transform_mod
 
-local eq = function(a, b)
+local eq = assert.are.same
-  assert.are.same(a, b)
-end
 
 describe("actions", function()
   it("should allow creating custom actions", function()
@@ -207,6 +205,29 @@ describe("actions", function()
     eq(true, called_post)
   end)
 
+  it("static_pre static_post", function()
+    local called_pre = false
+    local called_post = false
+    local static_post = 0
+    local a = transform_mod {
+      x = {
+        pre = function()
+          called_pre = true
+        end,
+        action = function()
+          return "x"
+        end,
+        post = function()
+          called_post = true
+        end,
+      },
+    }
+
+    eq("x", a.x())
+    eq(true, called_pre)
+    eq(true, called_post)
+  end)
+
   it("can call both", function()
     local a = transform_mod {
       x = function()
@@ -298,6 +319,102 @@ describe("actions", function()
     eq("modified: 5", a.x(5))
   end)
 
+  it("handles add with two different tables", function()
+    local count_a = 0
+    local count_b = 0
+    local a = transform_mod {
+      x = function()
+        count_a = count_a + 1
+      end,
+    }
+    local b = transform_mod {
+      y = function()
+        count_b = count_b + 1
+      end,
+    }
+
+    local called_count = 0
+    local count_inc = function()
+      called_count = called_count + 1
+    end
+
+    a.x:enhance {
+      post = count_inc,
+    }
+    b.y:enhance {
+      post = count_inc,
+    }
+
+    local x_plus_y = a.x + b.y
+    x_plus_y()
+
+    eq(2, called_count)
+    eq(1, count_a)
+    eq(1, count_b)
+  end)
+
+  it("handles tripple concat with static pre post", function()
+    local count_a = 0
+    local count_b = 0
+    local count_c = 0
+    local static_pre = 0
+    local static_post = 0
+    local a = transform_mod {
+      x = {
+        pre = function()
+          static_pre = static_pre + 1
+        end,
+        action = function()
+          count_a = count_a + 1
+        end,
+        post = function()
+          static_post = static_post + 1
+        end,
+      },
+    }
+    local b = transform_mod {
+      y = {
+        pre = function()
+          static_pre = static_pre + 1
+        end,
+        action = function()
+          count_b = count_b + 1
+        end,
+        post = function()
+          static_post = static_post + 1
+        end,
+      },
+    }
+    local c = transform_mod {
+      z = {
+        pre = function()
+          static_pre = static_pre + 1
+        end,
+        action = function()
+          count_c = count_c + 1
+        end,
+        post = function()
+          static_post = static_post + 1
+        end,
+      },
+    }
+
+    local replace_count = 0
+    a.x:replace(function()
+      replace_count = replace_count + 1
+    end)
+
+    local x_plus_y_plus_z = a.x + b.y + c.z
+    x_plus_y_plus_z()
+
+    eq(0, count_a)
+    eq(1, count_b)
+    eq(1, count_c)
+    eq(1, replace_count)
+    eq(3, static_pre)
+    eq(3, static_post)
+  end)
+
   describe("action_set", function()
     it("can replace `action_set.edit`", function()
       action_set.edit:replace(function(_, arg)