refactor(lsp): turn completion popup and request into classes

lua/lsp/completion/init.lua

@@ -1,8 +1,10 @@
-local popup = require("lsp.completion.popup")
+local Popup = require("lsp.completion.popup")
 local request = require("lsp.completion.request")
 
 local GROUP = vim.api.nvim_create_augroup("ow.lsp.completion", { clear = true })
 
+local popup = Popup.new()
+
 local M = {}
 
 ---@param capabilities lsp.ClientCapabilities
@@ -48,7 +50,9 @@ function M.setup()
             local client = client_id and vim.lsp.get_client_by_id(client_id)
 
             if not lsp_item or not client then
-                vim.schedule(popup.close)
+                vim.schedule(function()
+                    popup:close()
+                end)
                 return
             end
 
@@ -67,7 +71,7 @@ function M.setup()
                     vim.lsp.protocol.Methods.completionItem_resolve
                 )
             then
-                popup.dispatch_resolve(
+                popup:dispatch_resolve(
                     client,
                     lsp_item,
                     ft,
@@ -77,7 +81,7 @@ function M.setup()
                 )
             else
                 vim.schedule(function()
-                    popup.show_for(lsp_item, ft, pum)
+                    popup:show(lsp_item, ft, pum)
                 end)
             end
         end,
@@ -85,14 +89,16 @@ function M.setup()
 
     vim.api.nvim_create_autocmd({ "CompleteDonePre", "InsertLeave" }, {
         group = GROUP,
-        callback = popup.close,
+        callback = function()
+            popup:close()
+        end,
     })
 
     ---@param key string
     ---@param action fun()
     local function scroll_map(key, action)
         vim.keymap.set("i", key, function()
-            if popup.is_visible() then
+            if popup:is_visible() then
                 vim.schedule(action)
                 return ""
             end
@@ -100,16 +106,16 @@ function M.setup()
         end, { expr = true, replace_keycodes = true })
     end
     scroll_map("<C-d>", function()
-        popup.scroll_half(vim.keycode("<C-e>"))
+        popup:scroll_half(vim.keycode("<C-e>"))
     end)
     scroll_map("<C-u>", function()
-        popup.scroll_half(vim.keycode("<C-y>"))
+        popup:scroll_half(vim.keycode("<C-y>"))
     end)
     scroll_map("<C-j>", function()
-        popup.scroll_line(vim.keycode("<C-e>"))
+        popup:scroll_line(vim.keycode("<C-e>"))
     end)
     scroll_map("<C-k>", function()
-        popup.scroll_line(vim.keycode("<C-y>"))
+        popup:scroll_line(vim.keycode("<C-y>"))
     end)
 end
 

lua/lsp/completion/popup.lua

@@ -1,10 +1,9 @@
 local MAX_WIDTH = 80
 local MAX_HEIGHT = 20
+local HALF_HEIGHT = math.floor(MAX_HEIGHT / 2)
 
 local NS = vim.api.nvim_create_namespace("ow.lsp.completion.popup")
 
-local M = {}
-
 ---@class ow.lsp.completion.Pum
 ---@field row integer
 ---@field col integer
@@ -16,18 +15,6 @@ local M = {}
 ---@field client vim.lsp.Client
 ---@field id integer
 
----@class ow.lsp.completion.Popup
----@field winid integer?
----@field bufnr integer?
----@field pending ow.lsp.completion.PendingResolve?
-
----@type ow.lsp.completion.Popup
-local popup = {
-    winid = nil,
-    bufnr = nil,
-    pending = nil,
-}
-
 ---@param ft string
 ---@param text string
 ---@return string
@@ -41,139 +28,6 @@ local function signature_of(item)
     return item.detail or vim.tbl_get(item, "labelDetails", "description") or ""
 end
 
-local function cancel_pending()
-    if popup.pending then
-        pcall(
-            popup.pending.client.cancel_request,
-            popup.pending.client,
-            popup.pending.id
-        )
-        popup.pending = nil
-    end
-end
-
----@return integer bufnr
-local function ensure_buffer()
-    if not popup.bufnr or not vim.api.nvim_buf_is_valid(popup.bufnr) then
-        popup.bufnr = vim.api.nvim_create_buf(false, true)
-        vim.bo[popup.bufnr].buftype = "nofile"
-        vim.bo[popup.bufnr].bufhidden = "hide"
-        vim.bo[popup.bufnr].swapfile = false
-        pcall(vim.treesitter.start, popup.bufnr, "markdown")
-    end
-    return popup.bufnr
-end
-
-local function update_indicators()
-    if not popup.winid or not vim.api.nvim_win_is_valid(popup.winid) then
-        return
-    end
-    local visible = vim.api.nvim_win_get_height(popup.winid)
-    local topline, botline =
-        unpack(vim.api.nvim_win_call(popup.winid, function()
-            return { vim.fn.line("w0"), vim.fn.line("w$") }
-        end))
-    local ok_total, info_total =
-        pcall(vim.api.nvim_win_text_height, popup.winid, {})
-    local total = ok_total and info_total.all or visible
-
-    local display_topline = 1
-    if topline > 1 then
-        local ok, info = pcall(vim.api.nvim_win_text_height, popup.winid, {
-            end_row = topline - 2,
-        })
-        if ok then
-            display_topline = (info.all or 0) + 1
-        end
-    end
-    local display_bot = display_topline + visible - 1
-
-    local has_above = display_topline > 1
-    local has_below = display_bot < total
-        and botline
-            < vim.api.nvim_buf_line_count(vim.api.nvim_win_get_buf(popup.winid))
-    pcall(vim.api.nvim_win_set_config, popup.winid, {
-        title = has_above and { { "▲ ", "FloatBorder" } } or "",
-        title_pos = has_above and "right" or nil,
-        footer = has_below and { { "▼ ", "FloatBorder" } } or "",
-        footer_pos = has_below and "right" or nil,
-    })
-end
-
-function M.close()
-    cancel_pending()
-    if popup.winid and vim.api.nvim_win_is_valid(popup.winid) then
-        pcall(vim.api.nvim_win_close, popup.winid, true)
-    end
-    popup.winid = nil
-end
-
----@param content string
----@param pum ow.lsp.completion.Pum
----@param width integer
-local function show(content, pum, width)
-    local bufnr = ensure_buffer()
-    local lines = vim.split(content, "\n", { plain = true })
-    vim.api.nvim_buf_set_lines(bufnr, 0, -1, false, lines)
-
-    vim.api.nvim_buf_clear_namespace(bufnr, NS, 0, -1)
-    for i, line in ipairs(lines) do
-        if line ~= "" and line:gsub("─", "") == "" then
-            vim.api.nvim_buf_set_extmark(bufnr, NS, i - 1, 0, {
-                end_row = i - 1,
-                end_col = #line,
-                hl_group = "FloatBorder",
-                priority = 200,
-            })
-        end
-    end
-
-    width = math.min(width, MAX_WIDTH)
-    local height = math.min(#lines, MAX_HEIGHT)
-
-    local right_edge = pum.col + pum.width + (pum.scrollbar and 1 or 0)
-    local right_space = vim.o.columns - right_edge
-    local col
-    if right_space >= width + 2 then
-        col = right_edge
-    else
-        col = math.max(pum.col - width - 2, 0)
-    end
-
-    local cfg = {
-        relative = "editor",
-        row = pum.row,
-        col = col,
-        width = width,
-        height = height,
-        border = "rounded",
-        focusable = false,
-        style = "minimal",
-    }
-
-    if popup.winid and vim.api.nvim_win_is_valid(popup.winid) then
-        pcall(vim.api.nvim_win_set_config, popup.winid, cfg)
-    else
-        cfg.noautocmd = true
-        popup.winid = vim.api.nvim_open_win(bufnr, false, cfg)
-        vim.wo[popup.winid].wrap = true
-        vim.wo[popup.winid].linebreak = true
-        vim.wo[popup.winid].conceallevel = 2
-    end
-    pcall(vim.api.nvim_win_set_cursor, popup.winid, { 1, 0 })
-
-    local ok, info = pcall(vim.api.nvim_win_text_height, popup.winid, {})
-    if ok and info.all and info.all ~= height then
-        pcall(
-            vim.api.nvim_win_set_height,
-            popup.winid,
-            math.min(info.all, MAX_HEIGHT)
-        )
-    end
-
-    update_indicators()
-end
-
 ---@param item lsp.CompletionItem
 ---@param ft string
 ---@return string? content
@@ -220,35 +74,64 @@ local function build_content(item, ft)
     return table.concat(sections, sep), max_w
 end
 
+---@class ow.lsp.completion.Popup
+---@field private winid integer?
+---@field private bufnr integer?
+---@field private pending ow.lsp.completion.PendingResolve?
+local Popup = {}
+Popup.__index = Popup
+
+---@return ow.lsp.completion.Popup
+function Popup.new()
+    return setmetatable({
+        winid = nil,
+        bufnr = nil,
+        pending = nil,
+    }, Popup)
+end
+
+---@return boolean
+function Popup:is_visible()
+    return self.winid ~= nil and vim.api.nvim_win_is_valid(self.winid)
+end
+
+function Popup:close()
+    self:cancel_pending()
+    if self:is_visible() then
+        vim.api.nvim_win_close(self.winid, true)
+    end
+    self.winid = nil
+end
+
 --- Build content for `item` and show, or close if there's nothing to render.
 ---@param item lsp.CompletionItem
 ---@param ft string
 ---@param pum ow.lsp.completion.Pum
-function M.show_for(item, ft, pum)
+function Popup:show(item, ft, pum)
     local content, width = build_content(item, ft)
     if content and width then
-        show(content, pum, width)
+        self:render(content, pum, width)
     else
-        M.close()
+        self:close()
     end
 end
 
 --- Cancel any in-flight resolve, dispatch a fresh one for `item`, and on
 --- response render the resolved popup. If the user moved the selection
---- before the response landed (`completed.word` mismatch), do nothing.
+--- before the response landed (word mismatch), do nothing.
 ---@param client vim.lsp.Client
 ---@param item lsp.CompletionItem
 ---@param ft string
 ---@param pum ow.lsp.completion.Pum
 ---@param word string
 ---@param buf integer
-function M.dispatch_resolve(client, item, ft, pum, word, buf)
+function Popup:dispatch_resolve(client, item, ft, pum, word, buf)
-    cancel_pending()
+    self:cancel_pending()
     local _, request_id = client:request(
         vim.lsp.protocol.Methods.completionItem_resolve,
         item,
         function(err, result)
-            popup.pending = nil
+            self.pending = nil
             if err or not result then
                 return
             end
@@ -256,40 +139,153 @@ function M.dispatch_resolve(client, item, ft, pum, word, buf)
             if (vim.tbl_get(cur, "completed", "word") or "") ~= word then
                 return
             end
-            M.show_for(result, ft, pum)
+            self:show(result, ft, pum)
         end,
         buf
     )
     if request_id then
-        popup.pending = { client = client, id = request_id }
+        self.pending = { client = client, id = request_id }
     end
 end
 
----@return boolean
-function M.is_visible()
-    return popup.winid ~= nil and vim.api.nvim_win_is_valid(popup.winid)
-end
-
 ---@param direction string  single-line scroll keycode (<C-e> or <C-y>)
+function Popup:scroll_line(direction)
+    self:scroll(direction, 1)
+end
+
+---@param direction string
+function Popup:scroll_half(direction)
+    self:scroll(direction, HALF_HEIGHT)
+end
+
+---@param content string
+---@param pum ow.lsp.completion.Pum
+---@param width integer
+function Popup:render(content, pum, width)
+    self:ensure_buffer()
+    local lines = vim.split(content, "\n", { plain = true })
+    vim.api.nvim_buf_set_lines(self.bufnr, 0, -1, false, lines)
+
+    vim.api.nvim_buf_clear_namespace(self.bufnr, NS, 0, -1)
+    for i, line in ipairs(lines) do
+        if line ~= "" and line:gsub("─", "") == "" then
+            vim.api.nvim_buf_set_extmark(self.bufnr, NS, i - 1, 0, {
+                end_row = i - 1,
+                end_col = #line,
+                hl_group = "FloatBorder",
+                priority = 200,
+            })
+        end
+    end
+
+    width = math.min(width, MAX_WIDTH)
+    local height = math.min(#lines, MAX_HEIGHT)
+
+    local right_edge = pum.col + pum.width + (pum.scrollbar and 1 or 0)
+    local right_space = vim.o.columns - right_edge
+    local col
+    if right_space >= width + 2 then
+        col = right_edge
+    else
+        col = math.max(pum.col - width - 2, 0)
+    end
+
+    local cfg = {
+        relative = "editor",
+        row = pum.row,
+        col = col,
+        width = width,
+        height = height,
+        border = "rounded",
+        focusable = false,
+        style = "minimal",
+    }
+
+    if self:is_visible() then
+        vim.api.nvim_win_set_config(self.winid, cfg)
+    else
+        cfg.noautocmd = true
+        self.winid = vim.api.nvim_open_win(self.bufnr, false, cfg)
+        vim.wo[self.winid].wrap = true
+        vim.wo[self.winid].linebreak = true
+        vim.wo[self.winid].conceallevel = 2
+    end
+    vim.api.nvim_win_set_cursor(self.winid, { 1, 0 })
+
+    local actual = vim.api.nvim_win_text_height(self.winid, {
+        max_height = MAX_HEIGHT,
+    }).all
+    if actual ~= height then
+        vim.api.nvim_win_set_height(self.winid, actual)
+    end
+
+    self:update_indicators()
+end
+
+---@param direction string
 ---@param count integer
-local function scroll(direction, count)
+function Popup:scroll(direction, count)
-    if not M.is_visible() then
+    if not self:is_visible() then
         return
     end
-    vim.api.nvim_win_call(popup.winid, function()
+    vim.api.nvim_win_call(self.winid, function()
         vim.cmd.normal({ args = { count .. direction }, bang = true })
     end)
-    update_indicators()
+    self:update_indicators()
 end
 
----@param direction string  single-line scroll keycode (<C-e> or <C-y>)
+function Popup:cancel_pending()
-function M.scroll_line(direction)
+    if self.pending then
-    scroll(direction, 1)
+        self.pending.client:cancel_request(self.pending.id)
+        self.pending = nil
+    end
 end
 
----@param direction string  single-line scroll keycode (<C-e> or <C-y>)
+function Popup:ensure_buffer()
-function M.scroll_half(direction)
+    if self.bufnr and vim.api.nvim_buf_is_valid(self.bufnr) then
-    scroll(direction, math.floor(MAX_HEIGHT / 2))
+        return
+    end
+    self.bufnr = vim.api.nvim_create_buf(false, true)
+    vim.bo[self.bufnr].buftype = "nofile"
+    vim.bo[self.bufnr].bufhidden = "hide"
+    vim.bo[self.bufnr].swapfile = false
+    -- Markdown parser may not be installed; fall back to no highlighting.
+    pcall(vim.treesitter.start, self.bufnr, "markdown")
 end
 
-return M
+function Popup:update_indicators()
+    if not self:is_visible() then
+        return
+    end
+
+    local visible = vim.api.nvim_win_get_height(self.winid)
+    local topline, botline = unpack(vim.api.nvim_win_call(self.winid, function()
+        return { vim.fn.line("w0"), vim.fn.line("w$") }
+    end))
+
+    local display_topline = 1
+    if topline > 1 then
+        display_topline = vim.api.nvim_win_text_height(self.winid, {
+            end_row = topline - 2,
+        }).all + 1
+    end
+    local display_bot = display_topline + visible - 1
+
+    local total = vim.api.nvim_win_text_height(self.winid, {
+        max_height = display_bot + 1,
+    }).all
+
+    local has_above = display_topline > 1
+    local has_below = display_bot < total
+        and botline
+            < vim.api.nvim_buf_line_count(vim.api.nvim_win_get_buf(self.winid))
+
+    vim.api.nvim_win_set_config(self.winid, {
+        title = has_above and { { "▲ ", "FloatBorder" } } or "",
+        title_pos = has_above and "right" or nil,
+        footer = has_below and { { "▼ ", "FloatBorder" } } or "",
+        footer_pos = has_below and "right" or nil,
+    })
+end
+
+return Popup

lua/lsp/completion/request.lua

@@ -3,39 +3,6 @@ local util = require("util")
 
 local REQUEST_DEBOUNCE_MS = 100
 
-local M = {}
-
----@class ow.lsp.completion.Request
----@field generation integer
----@field phase ('awaiting' | 'ready' | 'done')?
----@field result table?
----@field cancel function?
-
----@type ow.lsp.completion.Request
-local request = {
-    generation = 0,
-    phase = nil,
-    result = nil,
-    cancel = nil,
-}
-
-local function discard_request()
-    if request.cancel then
-        pcall(request.cancel)
-    end
-    request.generation = request.generation + 1
-    request.phase = nil
-    request.result = nil
-    request.cancel = nil
-end
-
-local function buffer_has_completion_client()
-    return #vim.lsp.get_clients({
-        bufnr = 0,
-        method = vim.lsp.protocol.Methods.textDocument_completion,
-    }) > 0
-end
-
 --- Normalize an `itemDefaults.editRange` to a plain Range, since it may be
 --- either `Range` or `{ insert: Range, replace: Range }`.
 ---@param edit_range table?
@@ -83,19 +50,6 @@ local function response_edit_start(response)
     return nil
 end
 
----@return integer byte_col  0-indexed byte column for completefunc findstart
-local function resolve_start_col()
-    for _, response in pairs(request.result or {}) do
-        local col = response_edit_start(response)
-        if col then
-            return col
-        end
-    end
-    local line = vim.api.nvim_get_current_line()
-    local cursor_col = vim.fn.col(".") - 1
-    return vim.fn.match(line:sub(1, cursor_col), "\\k*$")
-end
-
 ---@param item lsp.CompletionItem
 ---@return string
 local function item_word(item)
@@ -129,11 +83,14 @@ local function apply_defaults(items, defaults)
     end
 end
 
+--- Transform raw LSP completion responses into Vim |complete()| items,
+--- filtered by `base` and sorted by sortText/label.
+---@param responses table  map of client_id -> response from buf_request_all
 ---@param base string
 ---@return table[]
-local function to_complete_items(base)
+local function build_items(responses, base)
     local entries = {}
-    for client_id, response in pairs(request.result or {}) do
+    for client_id, response in pairs(responses) do
         if response.result and not (response.err or response.error) then
             local raw = response.result.items or response.result
             if type(raw) == "table" then
@@ -187,39 +144,11 @@ local function to_complete_items(base)
     return result
 end
 
-local function feed_user_completion()
+local function buffer_has_completion_client()
-    if vim.fn.mode() ~= "i" or vim.fn.pumvisible() ~= 0 then
+    return #vim.lsp.get_clients({
-        return
+        bufnr = 0,
-    end
+        method = vim.lsp.protocol.Methods.textDocument_completion,
-    vim.api.nvim_feedkeys(vim.keycode("<C-x><C-o>"), "n", false)
+    }) > 0
-end
-
----@param trigger_kind integer
----@param trigger_char string?
-local function dispatch_request(trigger_kind, trigger_char)
-    discard_request()
-    request.phase = "awaiting"
-    local gen = request.generation
-    local buf = vim.api.nvim_get_current_buf()
-    local params = vim.lsp.util.make_position_params(0, "utf-16")
-    ---@cast params lsp.CompletionParams
-    params.context = {
-        triggerKind = trigger_kind,
-        triggerCharacter = trigger_char,
-    }
-    request.cancel = vim.lsp.buf_request_all(
-        buf,
-        vim.lsp.protocol.Methods.textDocument_completion,
-        params,
-        function(result)
-            if request.generation ~= gen or request.phase ~= "awaiting" then
-                return
-            end
-            request.phase = "ready"
-            request.result = result
-            feed_user_completion()
-        end
-    )
 end
 
 ---@param char string
@@ -243,13 +172,117 @@ local function is_trigger_char(char)
     return false
 end
 
+local function feed_omnifunc()
+    if vim.fn.mode() ~= "i" or vim.fn.pumvisible() ~= 0 then
+        return
+    end
+    vim.api.nvim_feedkeys(vim.keycode("<C-x><C-o>"), "n", false)
+end
+
+---@class ow.lsp.completion.Request
+---@field private generation integer
+---@field private phase ('awaiting' | 'ready' | 'done')?
+---@field private result table?
+---@field private cancel function?
+local Request = {}
+Request.__index = Request
+
+---@return ow.lsp.completion.Request
+function Request.new()
+    return setmetatable({
+        generation = 0,
+        phase = nil,
+        result = nil,
+        cancel = nil,
+    }, Request)
+end
+
+---@return boolean
+function Request:is_awaiting()
+    return self.phase == "awaiting"
+end
+
+---@return boolean
+function Request:is_ready()
+    return self.phase == "ready"
+end
+
+--- Cancel any in-flight LSP request and clear cached results.
+function Request:discard()
+    if self.cancel then
+        pcall(self.cancel)
+    end
+    self.generation = self.generation + 1
+    self.phase = nil
+    self.result = nil
+    self.cancel = nil
+end
+
+---@param trigger_kind integer
+---@param trigger_char string?
+function Request:dispatch(trigger_kind, trigger_char)
+    self:discard()
+    self.phase = "awaiting"
+    local gen = self.generation
+    local buf = vim.api.nvim_get_current_buf()
+    local params = vim.lsp.util.make_position_params(0, "utf-16")
+    ---@cast params lsp.CompletionParams
+    params.context = {
+        triggerKind = trigger_kind,
+        triggerCharacter = trigger_char,
+    }
+    self.cancel = vim.lsp.buf_request_all(
+        buf,
+        vim.lsp.protocol.Methods.textDocument_completion,
+        params,
+        function(result)
+            if self.generation ~= gen or self.phase ~= "awaiting" then
+                return
+            end
+            self.phase = "ready"
+            self.result = result
+            feed_omnifunc()
+        end
+    )
+end
+
+--- Byte column where the cached LSP edits start, for |complete-functions|
+--- `findstart == 1`. Falls back to the regex end of the word under cursor.
+---@return integer
+function Request:start_col()
+    for _, response in pairs(self.result or {}) do
+        local col = response_edit_start(response)
+        if col then
+            return col
+        end
+    end
+    local line = vim.api.nvim_get_current_line()
+    local cursor_col = vim.fn.col(".") - 1
+    return vim.fn.match(line:sub(1, cursor_col), "\\k*$")
+end
+
+--- Build the Vim |complete()| items from the cached LSP results filtered by
+--- `base`, and transition this request to the "done" phase. Subsequent
+--- completion triggers will dispatch a fresh request.
+---@param base string
+---@return table[]
+function Request:consume(base)
+    local items = build_items(self.result or {}, base)
+    self.phase = "done"
+    return items
+end
+
+local request = Request.new()
+
 local debounce = util.debounce(function(_, trigger_kind, char)
     if vim.fn.mode() ~= "i" then
         return
     end
-    dispatch_request(trigger_kind, char)
+    request:dispatch(trigger_kind, char)
 end, REQUEST_DEBOUNCE_MS)
 
+local M = {}
+
 function M.on_insert_char_pre()
     local char = vim.v.char
     if char == "" then
@@ -273,6 +306,8 @@ function M.on_insert_char_pre()
     debounce:call(nil, kind_num, is_trigger and char or nil)
 end
 
+-- Global entry point for Vim's 'omnifunc' option. Referenced via
+-- `v:lua.ow_lsp_completion.omnifunc` from on_attach's `vim.bo.omnifunc`.
 _G.ow_lsp_completion = _G.ow_lsp_completion or {}
 
 --- Returns cached items without re-requesting, which is what lets Vim filter
@@ -281,22 +316,17 @@ _G.ow_lsp_completion = _G.ow_lsp_completion or {}
 ---@param base string
 ---@return integer | table
 function _G.ow_lsp_completion.omnifunc(findstart, base)
-    if not buffer_has_completion_client() or request.phase == "awaiting" then
+    if not buffer_has_completion_client() or request:is_awaiting() then
         return findstart == 1 and -3 or {}
     end
-
+    if not request:is_ready() then
-    if request.phase ~= "ready" then
+        request:dispatch(vim.lsp.protocol.CompletionTriggerKind.Invoked)
-        dispatch_request(vim.lsp.protocol.CompletionTriggerKind.Invoked)
         return findstart == 1 and -3 or {}
     end
-
     if findstart == 1 then
-        return resolve_start_col()
+        return request:start_col()
     end
-
+    return request:consume(base)
-    local items = to_complete_items(base)
-    request.phase = "done"
-    return items
 end
 
 return M