refactor(completion): evolve Request into Session + surface-level cleanup

lua/lsp/completion/init.lua

@@ -1,6 +1,6 @@
 local Item = require("lsp.completion.item")
 local Popup = require("lsp.completion.popup")
-local request = require("lsp.completion.request")
+local session = require("lsp.completion.session")
 
 local GROUP = vim.api.nvim_create_augroup("ow.lsp.completion", { clear = true })
 
@@ -23,7 +23,7 @@ local function on_attach(client, buf)
     vim.api.nvim_create_autocmd("InsertCharPre", {
         buffer = buf,
         group = GROUP,
-        callback = request.on_insert_char_pre,
+        callback = session.on_insert_char_pre,
     })
 end
 
@@ -207,6 +207,13 @@ function M.setup()
         end
         return "<CR>"
     end, { expr = true, replace_keycodes = true })
+
+    vim.keymap.set(
+        "i",
+        "<C-x><C-o>",
+        session.trigger_manual,
+        { expr = true, remap = false }
+    )
 end
 
 return M

lua/lsp/completion/item.lua

@@ -1,11 +1,5 @@
-local SNIPPET = vim.lsp.protocol.InsertTextFormat.Snippet
-
----@param raw lsp.CompletionItem
----@return string?
-local function edit_text(raw)
-    local edit = raw.textEdit
-    return (type(edit) == "table" and edit.newText) or raw.insertText
-end
+local SNIPPET_FORMAT = vim.lsp.protocol.InsertTextFormat.Snippet
+local SNIPPET_KIND = vim.lsp.protocol.CompletionItemKind.Snippet
 
 ---@param raw lsp.CompletionItem
 ---@return string
@@ -14,26 +8,62 @@ local function label_stem(raw)
 end
 
 ---@param raw lsp.CompletionItem
----@return string?
-local function extract_doc(raw)
-    local doc = raw.documentation
-    if type(doc) == "table" then
-        return doc.value
+---@return string
+local function edit_text(raw)
+    if raw.textEdit then
+        return raw.textEdit.newText
     end
-    ---@cast doc string?
-    return doc
+
+    return raw.insertText or raw.label
+end
+
+---@param raw lsp.CompletionItem
+---@return string
+local function get_word(raw)
+    if raw.insertTextFormat == SNIPPET_FORMAT then
+        return raw.filterText or label_stem(raw)
+    end
+    return edit_text(raw)
+end
+
+---@param raw lsp.CompletionItem
+---@return string
+local function get_abbr(raw)
+    local abbr = label_stem(raw)
+    if raw.kind == SNIPPET_KIND then
+        abbr = abbr .. "~"
+    end
+    return abbr
 end
 
 ---@param raw lsp.CompletionItem
 ---@return string?
-local function extract_detail(raw)
+local function get_detail(raw)
     return raw.detail or vim.tbl_get(raw, "labelDetails", "description")
 end
 
+---@param raw lsp.CompletionItem
+---@return string?
+local function get_doc(raw)
+    local doc = raw.documentation
+    if not doc then
+        return nil
+    end
+    return doc.value or doc
+end
+
+---@param raw lsp.CompletionItem
+---@return string?
+local function get_snippet(raw)
+    if raw.insertTextFormat == SNIPPET_FORMAT then
+        return edit_text(raw)
+    end
+    return nil
+end
+
 ---@class ow.lsp.completion.Item
 ---@field word string
 ---@field abbr string
----@field menu string
 ---@field detail string?
 ---@field doc string?
 ---@field snippet string?
@@ -46,22 +76,12 @@ Item.__index = Item
 ---@param client_id integer
 ---@return ow.lsp.completion.Item
 function Item.from_lsp(raw, client_id)
-    local is_snippet = raw.insertTextFormat == SNIPPET
-    local abbr = label_stem(raw)
-    local word
-    if is_snippet then
-        word = raw.filterText or abbr
-        abbr = abbr .. "~"
-    else
-        word = edit_text(raw) or raw.label
-    end
     return setmetatable({
-        word = word,
-        abbr = abbr,
-        menu = vim.tbl_get(raw, "labelDetails", "detail") or "",
-        detail = extract_detail(raw),
-        doc = extract_doc(raw),
-        snippet = is_snippet and (edit_text(raw) or raw.label) or nil,
+        word = get_word(raw),
+        abbr = get_abbr(raw),
+        detail = get_detail(raw),
+        doc = get_doc(raw),
+        snippet = get_snippet(raw),
         client_id = client_id,
         raw = raw,
     }, Item)
@@ -70,10 +90,10 @@ end
 ---@param resolved lsp.CompletionItem
 function Item:apply_resolved(resolved)
     self.raw = vim.tbl_deep_extend("force", self.raw, resolved)
-    self.detail = extract_detail(self.raw)
-    self.doc = extract_doc(self.raw)
+    self.detail = get_detail(self.raw)
+    self.doc = get_doc(self.raw)
     if self.snippet then
-        self.snippet = edit_text(self.raw) or self.raw.label
+        self.snippet = edit_text(self.raw)
     end
 end
 

lua/lsp/completion/popup.lua

@@ -1,6 +1,7 @@
 local MAX_WIDTH = 80
 local MAX_HEIGHT = 20
 local HALF_HEIGHT = math.floor(MAX_HEIGHT / 2)
+local SNIPPET_KIND = vim.lsp.protocol.CompletionItemKind.Snippet
 
 local NS = vim.api.nvim_create_namespace("ow.lsp.completion.popup")
 
@@ -28,15 +29,16 @@ end
 ---@return integer? width
 local function build_content(item, ft)
     local sections = {}
+    if item.snippet and item.raw.kind == SNIPPET_KIND then
+        table.insert(sections, fence(ft, item.snippet))
+    else
         if item.detail then
             table.insert(sections, fence(ft, item.detail))
         end
-    if item.snippet then
-        table.insert(sections, fence(ft, item.snippet))
-    end
         if item.doc then
             table.insert(sections, item.doc)
         end
+    end
     if #sections == 0 then
         return nil, nil
     end

lua/lsp/completion/session.lua

@@ -5,7 +5,7 @@ local Item = require("lsp.completion.item")
 local kind = require("lsp.kind")
 local util = require("util")
 
-local REQUEST_DEBOUNCE_MS = 100
+local REQUEST_DEBOUNCE_MS = 50
 
 ---@param item_defaults? lsp.CompletionItemDefaults
 ---@return lsp.Range?
@@ -99,11 +99,12 @@ local function build_items(responses, base)
         end, entries)
     end
 
-    table.sort(entries, function(a, b)
-        local ka = a.item.sortText or a.item.label
-        local kb = b.item.sortText or b.item.label
-        return ka < kb
-    end)
+    -- for _, entry in ipairs(entries) do
+    --     entry.sort_key = entry.item.sortText or entry.item.label
+    -- end
+    -- table.sort(entries, function(a, b)
+    --     return a.sort_key < b.sort_key
+    -- end)
 
     ---@type vim.v.completed_item[]
     local result = {}
@@ -113,11 +114,8 @@ local function build_items(responses, base)
         result[#result + 1] = {
             word = item.word,
             abbr = item.abbr,
-            menu = item.menu,
             kind = kind_icon,
             kind_hlgroup = kind_hl,
-            -- non-empty so our CompleteChanged handler triggers resolve
-            info = " ",
             icase = 1,
             dup = 1,
             empty = 1,
@@ -134,6 +132,14 @@ local function buffer_has_completion_client()
     }) > 0
 end
 
+---@return integer start, integer cursor  both 0-indexed byte columns
+local function word_bounds()
+    local line = vim.api.nvim_get_current_line()
+    local cursor = vim.fn.col(".") - 1
+    local start = vim.fn.match(line:sub(1, cursor), "\\k*$")
+    return start, cursor
+end
+
 ---@param char string
 ---@return boolean
 local function is_trigger_char(char)
@@ -162,35 +168,37 @@ local function feed_omnifunc()
     vim.api.nvim_feedkeys(vim.keycode("<C-x><C-o>"), "n", false)
 end
 
----@class ow.lsp.completion.Request
+---@class ow.lsp.completion.Session
 ---@field private generation integer
 ---@field private phase ('awaiting' | 'ready' | 'done')?
 ---@field private result table<integer, ow.lsp.CompletionResponse>?
 ---@field private cancel function?
-local Request = {}
-Request.__index = Request
+---@field trigger_char string?
+local Session = {}
+Session.__index = Session
 
----@return ow.lsp.completion.Request
-function Request.new()
+---@return ow.lsp.completion.Session
+function Session.new()
     return setmetatable({
         generation = 0,
         phase = nil,
         result = nil,
         cancel = nil,
-    }, Request)
+        trigger_char = nil,
+    }, Session)
 end
 
 ---@return boolean
-function Request:is_awaiting()
+function Session:is_awaiting()
     return self.phase == "awaiting"
 end
 
 ---@return boolean
-function Request:is_ready()
+function Session:is_ready()
     return self.phase == "ready"
 end
 
-function Request:discard()
+function Session:discard()
     if self.cancel then
         pcall(self.cancel)
     end
@@ -202,9 +210,10 @@ end
 
 ---@param trigger_kind integer
 ---@param trigger_char? string
-function Request:dispatch(trigger_kind, trigger_char)
+function Session:dispatch(trigger_kind, trigger_char)
     self:discard()
     self.phase = "awaiting"
+    self.trigger_char = trigger_char
     local gen = self.generation
     local buf = vim.api.nvim_get_current_buf()
     local params = vim.lsp.util.make_position_params(0, "utf-16")
@@ -229,42 +238,57 @@ function Request:dispatch(trigger_kind, trigger_char)
 end
 
 ---@return integer
-function Request:start_col()
+function Session: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*$")
+    local start = word_bounds()
+    return start
 end
 
 ---@param base string
 ---@return vim.v.completed_item[]
-function Request:consume(base)
+function Session:finalize(base)
     local items = build_items(self.result or {}, base)
     self.phase = "done"
     return items
 end
 
-local request = Request.new()
+---@type ow.lsp.completion.Session?
+local session = nil
 
-local debounce = util.debounce(function(_, trigger_kind, char)
+local dispatcher = util.debounce(function(_, trigger_kind, char)
     if vim.fn.mode() ~= "i" then
         return
     end
-    request:dispatch(trigger_kind, char)
+    if not session then
+        session = Session.new()
+    end
+    session:dispatch(trigger_kind, char)
 end, REQUEST_DEBOUNCE_MS)
 
+-- Set by `trigger_manual` when the user explicitly invokes completion via
+-- <C-x><C-o>. Survives the dispatch+response round-trip so the omnifunc knows
+-- to skip the "no word before cursor" guard. Reset on the next auto trigger.
+local manual_pending = false
+
 local M = {}
 
+---Expose for the <C-x><C-o> keymap wrapper.
+function M.trigger_manual()
+    manual_pending = true
+    return vim.keycode("<C-x><C-o>")
+end
+
 function M.on_insert_char_pre()
     local char = vim.v.char
     if char == "" then
         return
     end
+    manual_pending = false
     local is_word = char:match("[%w_]") ~= nil
     local is_trigger = not is_word and is_trigger_char(char)
     if not (is_word or is_trigger) then
@@ -280,7 +304,7 @@ function M.on_insert_char_pre()
     local kind_num = is_trigger
             and vim.lsp.protocol.CompletionTriggerKind.TriggerCharacter
         or vim.lsp.protocol.CompletionTriggerKind.Invoked
-    debounce:call(nil, kind_num, is_trigger and char or nil)
+    dispatcher:call(nil, kind_num, is_trigger and char or nil)
 end
 
 -- Global entry point for Vim's 'omnifunc' option. Referenced via
@@ -291,17 +315,34 @@ _G.ow_lsp_completion = _G.ow_lsp_completion or {}
 ---@param base string
 ---@return integer | vim.v.completed_item[]
 function _G.ow_lsp_completion.omnifunc(findstart, base)
-    if not buffer_has_completion_client() or request:is_awaiting() then
+    if not session then
+        session = Session.new()
+    end
+    if not buffer_has_completion_client() or session:is_awaiting() then
         return findstart == 1 and -3 or {}
     end
-    if not request:is_ready() then
-        request:dispatch(vim.lsp.protocol.CompletionTriggerKind.Invoked)
+    if
+        findstart == 1
+        and session:is_ready()
+        and not manual_pending
+        and not session.trigger_char
+    then
+        local start, cursor = word_bounds()
+        if start == cursor then
+            return -3
+        end
+    end
+    if not session:is_ready() then
+        session:dispatch(vim.lsp.protocol.CompletionTriggerKind.Invoked)
         return findstart == 1 and -3 or {}
     end
     if findstart == 1 then
-        return request:start_col()
+        return session:start_col()
     end
-    return request:consume(base)
+    local items = session:finalize(base)
+    session = nil
+    manual_pending = false
+    return items
 end
 
 return M