fix: robust task-CLI I/O (#5), prefix-preserving completion (#4), wrap option + focusable confirm picker (#3)

README.md

@@ -214,6 +214,7 @@ require("taskwarrior").setup({
   confirm = true,              -- show confirmation dialog before applying
   sort = "urgency-",           -- default sort (field+ for asc, field- for desc)
   group = nil,                 -- default group field (nil to disable)
+  wrap = true,                 -- line-wrap task buffers (false = one line per task)
   fields = nil,                -- fields to show (nil = all)
   capture_key = "<leader>ta",  -- global quick-capture (nil to disable)
   open_key = "<leader>tt",     -- global open-task-buffer (nil to disable)

doc/taskwarrior.txt

@@ -374,6 +374,7 @@ Full schema with defaults: >
       confirm           = true,
       sort              = "urgency-",
       group             = nil,
+      wrap              = true,       -- false = don't line-wrap task buffers
       fields            = nil,
       capture_key       = "<leader>ta",
       open_key          = "<leader>tt",

lua/taskwarrior/apply.lua

@@ -194,14 +194,20 @@ function M.on_write(bufnr, refresh_fn, do_apply_fn)
       prompt = string.format("Apply %d change(s)?", #actions)
     end
 
-    vim.ui.select(choices, { prompt = prompt }, function(choice)
-      if not choice or choice == "Cancel" then
-        vim.notify("taskwarrior.nvim: cancelled")
-        vim.fn.delete(tmpfile)
-        return
-      end
-      local apply_force = choice == "Apply force (overwrite external changes)"
-      do_apply_fn(bufnr, tmpfile, on_delete, { force = apply_force })
+    -- Deferred via vim.schedule: on_write runs inside the BufWriteCmd
+    -- handler, and float-based vim.ui.select backends (dressing, snacks,
+    -- telescope, …) opened from an autocmd context can't take focus — the
+    -- picker renders but the cursor stays in the task buffer (issue #3).
+    vim.schedule(function()
+      vim.ui.select(choices, { prompt = prompt }, function(choice)
+        if not choice or choice == "Cancel" then
+          vim.notify("taskwarrior.nvim: cancelled")
+          vim.fn.delete(tmpfile)
+          return
+        end
+        local apply_force = choice == "Apply force (overwrite external changes)"
+        do_apply_fn(bufnr, tmpfile, on_delete, { force = apply_force })
+      end)
     end)
   else
     if not force then

lua/taskwarrior/buffer.lua

@@ -112,13 +112,8 @@ local function apply_custom_sort(bufnr)
   -- Export tasks to get full data for the custom function
   local filter = vim.b[bufnr].task_filter or ""
   local export_filter = filter ~= "" and filter or "status:pending"
-  local cmd = string.format("task rc.bulk=0 rc.confirmation=off rc.json.array=on %s export", export_filter)
-  local out, ok = run(cmd)
-  if not ok or not out or out == "" then return end
-  local json_start = out:find("%[")
-  if json_start and json_start > 1 then out = out:sub(json_start) end
-  local parsed_ok, tasks = pcall(vim.fn.json_decode, out)
-  if not parsed_ok or type(tasks) ~= "table" then return end
+  local tasks = require("taskwarrior.taskmd").shell_export(export_filter)
+  if not tasks then return end
 
   -- Apply multiplicative urgency coefficients (same logic as taskmd.lua render).
   -- Non-numeric values go through user-configurable mappers.
@@ -332,23 +327,38 @@ end
 
 M._relative_date = relative_date  -- exported for e2e testing
 
+local es_ns = vim.api.nvim_create_namespace("taskwarrior_empty_state")
+
+-- Visible empty-state hint. A zero-task render is just the header comment,
+-- which conceallevel=3 hides entirely — the user sees a blank buffer with no
+-- explanation of why, and refresh looks like a no-op (issue #5). Rendered as
+-- virt_lines, not buffer text, so `:w` round-trips untouched.
+local function apply_empty_state(bufnr)
+  vim.api.nvim_buf_clear_namespace(bufnr, es_ns, 0, -1)
+  for _, line in ipairs(vim.api.nvim_buf_get_lines(bufnr, 0, -1, false)) do
+    if uuid_from_line(line) then return end
+  end
+  local cfg_ok, cfg = pcall(require, "taskwarrior.config")
+  local prefix = (cfg_ok and cfg.options.command_prefix) or "Tw"
+  local filter = vim.b[bufnr].task_filter
+  local shown = (filter and filter ~= "") and filter or "(all pending)"
+  pcall(vim.api.nvim_buf_set_extmark, bufnr, es_ns, 0, 0, {
+    virt_lines = {
+      { { "", "Comment" } },
+      { { "  No tasks match filter: " .. shown, "Comment" } },
+      { { ("  :%sFilter <expr> to change it · :%sAdd to create a task"):format(prefix, prefix), "Comment" } },
+    },
+  })
+end
+M._apply_empty_state = apply_empty_state  -- exported for testing
+
 local function apply_virtual_text(bufnr)
   vim.api.nvim_buf_clear_namespace(bufnr, vt_ns, 0, -1)
+  apply_empty_state(bufnr)
   local filter = vim.b[bufnr].task_filter or ""
   local export_filter = filter ~= "" and filter or "status:pending"
-  local cmd = string.format(
-    "task rc.bulk=0 rc.confirmation=off rc.json.array=on %s export", export_filter)
-  local out, ok = run(cmd)
-  if not ok or not out or out == "" then return end
-
-  -- Handle warnings before JSON
-  local json_start = out:find("%[")
-  if json_start and json_start > 1 then
-    out = out:sub(json_start)
-  end
-
-  local parsed_ok, tasks = pcall(vim.fn.json_decode, out)
-  if not parsed_ok or type(tasks) ~= "table" then return end
+  local tasks = require("taskwarrior.taskmd").shell_export(export_filter)
+  if not tasks then return end
 
   local config = require("taskwarrior.config")
   local icons = require("taskwarrior.icons")
@@ -1107,7 +1117,8 @@ function M.setup_buf_autocmds(bufnr, on_write_fn)
       -- Wrap prevents horizontal-scroll disorientation on j/k with long task
       -- lines. Without wrap, curswant preservation causes the viewport to
       -- shift horizontally, making it look like j "doesn't work".
-      vim.wo[0].wrap = true
+      -- Overridable via setup{ wrap = false } (issue #3).
+      vim.wo[0].wrap = require("taskwarrior.config").options.wrap ~= false
     end,
   })
 
@@ -1252,7 +1263,7 @@ function M.open_task_buf(filter_str, on_write_fn, detect_project_fn)
       vim.api.nvim_win_set_buf(0, b)
       vim.wo[0].conceallevel = 3
       vim.wo[0].concealcursor = "nvic"
-      vim.wo[0].wrap = true
+      vim.wo[0].wrap = config.options.wrap ~= false
       -- Reserve two sign cells for priority + status glyphs. `auto:2` only
       -- shows the column when a sign is present, so tasks with no priority
       -- or status don't waste horizontal space.
@@ -1286,7 +1297,7 @@ function M.open_task_buf(filter_str, on_write_fn, detect_project_fn)
   vim.api.nvim_win_set_buf(0, bufnr)
   vim.wo[0].conceallevel = 3
   vim.wo[0].concealcursor = "nvic"
-  vim.wo[0].wrap = true
+  vim.wo[0].wrap = config.options.wrap ~= false
 
   -- Set name safely — wipe stale buffer with same name if needed
   local buf_name = "Tasks: " .. filter_str
@@ -1350,7 +1361,7 @@ function M.open_float(filter_str)
   })
   vim.wo[win].conceallevel = 3
   vim.wo[win].concealcursor = "nvic"
-  vim.wo[win].wrap = true
+  vim.wo[win].wrap = config.options.wrap ~= false
 
   vim.keymap.set("n", "q", function()
     pcall(vim.api.nvim_win_close, win, true)

lua/taskwarrior/config.lua

@@ -19,6 +19,11 @@ M.defaults = {
 	confirm = true, -- show confirmation dialog before applying
 	sort = "urgency-", -- default sort
 	group = nil, -- default group field (nil to disable)
+	-- Line wrap in task buffers/floats. Default true: without wrap, curswant
+	-- preservation on long task lines makes j/k shift the viewport
+	-- horizontally ("j doesn't work"). Set false for one-line-per-task
+	-- (issue #3); long lines then extend past the right edge.
+	wrap = true,
 	fields = nil, -- fields to show (nil = all)
 	capture_key = "<leader>ta", -- global keybind for quick capture (nil to disable)
 	open_key = "<leader>tt", -- global keybind to open task buffer (nil to disable)

lua/taskwarrior/delegate.lua

@@ -23,19 +23,11 @@ function M.delegate_one()
     vim.notify("taskwarrior.nvim: no UUID on this line", vim.log.levels.WARN)
     return
   end
-  local out, ok = run(
-    string.format("task rc.bulk=0 rc.confirmation=off rc.json.array=on %s export", short_uuid))
-  if not ok or not out or out == "" then
+  local tasks = require("taskwarrior.taskmd").shell_export(short_uuid)
+  if not tasks or #tasks == 0 then
     vim.notify("taskwarrior.nvim: failed to export task", vim.log.levels.ERROR)
     return
   end
-  local json_start = out:find("%[")
-  if json_start and json_start > 1 then out = out:sub(json_start) end
-  local parsed_ok, tasks = pcall(vim.fn.json_decode, out)
-  if not parsed_ok or type(tasks) ~= "table" or #tasks == 0 then
-    vim.notify("taskwarrior.nvim: failed to parse task", vim.log.levels.ERROR)
-    return
-  end
   return tasks[1], short_uuid
 end
 
@@ -213,19 +205,11 @@ function M.collect(range)
   end
 
   local filter = table.concat(short_uuids, " ")
-  local out, ok = run(
-    string.format("task rc.bulk=0 rc.confirmation=off rc.json.array=on %s export", filter))
-  if not ok or not out or out == "" then
+  local tasks = require("taskwarrior.taskmd").shell_export(filter)
+  if not tasks or #tasks == 0 then
     vim.notify("taskwarrior.nvim: failed to export tasks", vim.log.levels.ERROR)
     return nil
   end
-  local json_start = out:find("%[")
-  if json_start and json_start > 1 then out = out:sub(json_start) end
-  local parsed_ok, tasks = pcall(vim.fn.json_decode, out)
-  if not parsed_ok or type(tasks) ~= "table" or #tasks == 0 then
-    vim.notify("taskwarrior.nvim: failed to parse tasks", vim.log.levels.ERROR)
-    return nil
-  end
 
   -- Preserve the order in which short_uuids appeared in the buffer.
   local by_short = {}

lua/taskwarrior/graph.lua

@@ -47,14 +47,8 @@ end
 
 function M.render(filter)
   filter = filter or "status:pending"
-  local cmd = string.format(
-    "task rc.bulk=0 rc.confirmation=off rc.json.array=on %s export", filter)
-  local out, ok = run(cmd)
-  if not ok or not out or out == "" then return nil end
-  local js = out:find("%[")
-  if js and js > 1 then out = out:sub(js) end
-  local parsed_ok, tasks = pcall(vim.fn.json_decode, out)
-  if not parsed_ok or type(tasks) ~= "table" then return nil end
+  local tasks = require("taskwarrior.taskmd").shell_export(filter)
+  if not tasks then return nil end
 
   local lines = {
     "# taskwarrior.nvim — dependency graph",

lua/taskwarrior/inbox.lua

@@ -20,18 +20,12 @@ function M.run(hours)
   -- Taskwarrior's entry.after: expects an ISO-like date. `now-Nh` is simpler.
   local filter = string.format(
     "status:pending entry.after:now-%dh project: -TAGGED", hours)
-  local cmd = string.format(
-    "task rc.bulk=0 rc.confirmation=off rc.json.array=on %s export", filter)
-  local out, ok = run(cmd)
-  if not ok then
+  local tasks = require("taskwarrior.taskmd").shell_export(filter)
+  if not tasks then
     require("taskwarrior.notify")("error",
       "taskwarrior.nvim: failed to fetch inbox", vim.log.levels.ERROR)
     return
   end
-  local js = out:find("%[")
-  if js and js > 1 then out = out:sub(js) end
-  local parsed_ok, tasks = pcall(vim.fn.json_decode, out)
-  if not parsed_ok or type(tasks) ~= "table" then tasks = {} end
 
   -- Guard: also filter client-side, because TW's `project:` (empty) filter
   -- can be finicky across TW versions.

lua/taskwarrior/init.lua

@@ -199,9 +199,31 @@ function M._setup_commands()
 end
 
 -- Completion callbacks (ArgLead, CmdLine, CursorPos) -> list of strings
-function M._complete_filter(arg_lead, cmd_line, _cursor_pos)
-  local words = vim.split(cmd_line, "%s+")
-  return complete_filter(words[#words] or "")
+--
+-- These back vim.fn.input() prompts, where <Tab> replaces the ENTIRE typed
+-- text with the chosen candidate (input() has no per-word completion). Each
+-- candidate must therefore carry the untouched leading tokens as a prefix —
+-- returning bare last-token candidates wipes the rest of the filter
+-- (issue #4).
+local function complete_last_token(cmd_line, complete_fn)
+  local prefix, last = cmd_line:match("^(.*%s)(%S*)$")
+  if not prefix then prefix, last = "", cmd_line end
+  local results = complete_fn(last or "")
+  if prefix ~= "" then
+    for i, r in ipairs(results) do results[i] = prefix .. r end
+  end
+  return results
+end
+
+function M._complete_filter(_arg_lead, cmd_line, _cursor_pos)
+  return complete_last_token(cmd_line or "", complete_filter)
+end
+
+-- Completion for the `gm` modify prompt (buffer.lua). Modify args share the
+-- filter vocabulary (+tag, project:, priority:, due:, …). Registered as
+-- "custom," completion, so return newline-separated matches.
+function M._complete_modify(_arg_lead, cmd_line, _cursor_pos)
+  return table.concat(complete_last_token(cmd_line or "", complete_filter), "\n")
 end
 
 function M._complete_sort(arg_lead, _cmd_line, _cursor_pos)
@@ -228,15 +250,7 @@ M.api = {}
 M.api.export = function(filter_args)
   filter_args = filter_args or {}
   local filter_str = type(filter_args) == "table" and table.concat(filter_args, " ") or filter_args
-  local cmd = string.format("task rc.bulk=0 rc.confirmation=off rc.json.array=on %s export",
-    filter_str)
-  local out, ok = run(cmd)
-  if not ok or not out or out == "" then return {} end
-  local json_start = out:find("%[")
-  if json_start and json_start > 1 then out = out:sub(json_start) end
-  local parsed_ok, tasks = pcall(vim.fn.json_decode, out)
-  if not parsed_ok or type(tasks) ~= "table" then return {} end
-  return tasks
+  return require("taskwarrior.taskmd").shell_export(filter_str) or {}
 end
 
 M.api.get_task_on_cursor = function()

lua/taskwarrior/modify.lua

@@ -141,13 +141,8 @@ end
 -- ---------------------------------------------------------------------------
 
 local function get_task_json(uuid)
-  local out, ok = run(string.format(
-    "task rc.bulk=0 rc.confirmation=off rc.json.array=on %s export", uuid))
-  if not ok or not out or out == "" then return nil end
-  local json_start = out:find("%[")
-  if json_start and json_start > 1 then out = out:sub(json_start) end
-  local parsed_ok, arr = pcall(vim.fn.json_decode, out)
-  if not parsed_ok or type(arr) ~= "table" or not arr[1] then return nil end
+  local arr = require("taskwarrior.taskmd").shell_export(uuid)
+  if not arr or not arr[1] then return nil end
   return arr[1]
 end
 
@@ -201,13 +196,8 @@ end
 
 --- Collect existing project names from pending tasks (de-duplicated, sorted).
 local function existing_projects()
-  local out, ok = run(
-    "task rc.bulk=0 rc.confirmation=off rc.json.array=on status:pending export")
-  if not ok or not out or out == "" then return {} end
-  local json_start = out:find("%[")
-  if json_start and json_start > 1 then out = out:sub(json_start) end
-  local parsed_ok, tasks = pcall(vim.fn.json_decode, out)
-  if not parsed_ok or type(tasks) ~= "table" then return {} end
+  local tasks = require("taskwarrior.taskmd").shell_export("status:pending")
+  if not tasks then return {} end
   local seen, names = {}, {}
   for _, t in ipairs(tasks) do
     if t.project and not seen[t.project] then
@@ -221,13 +211,8 @@ end
 
 --- Collect existing tags from pending tasks.
 local function existing_tags()
-  local out, ok = run(
-    "task rc.bulk=0 rc.confirmation=off rc.json.array=on status:pending export")
-  if not ok or not out or out == "" then return {} end
-  local json_start = out:find("%[")
-  if json_start and json_start > 1 then out = out:sub(json_start) end
-  local parsed_ok, tasks = pcall(vim.fn.json_decode, out)
-  if not parsed_ok or type(tasks) ~= "table" then return {} end
+  local tasks = require("taskwarrior.taskmd").shell_export("status:pending")
+  if not tasks then return {} end
   local seen, names = {}, {}
   for _, t in ipairs(tasks) do
     for _, tag in ipairs(t.tags or {}) do

lua/taskwarrior/statusline.lua

@@ -17,12 +17,8 @@ end
 
 local function compute()
   local today = os.date("!%Y-%m-%d")
-  local out = vim.fn.system(
-    "task rc.bulk=0 rc.confirmation=off rc.json.array=on status:pending export")
-  local json_start = out:find("%[")
-  if json_start and json_start > 1 then out = out:sub(json_start) end
-  local ok, tasks = pcall(vim.fn.json_decode, out)
-  if not ok or type(tasks) ~= "table" then return "" end
+  local tasks = require("taskwarrior.taskmd").shell_export("status:pending")
+  if not tasks then return "" end
 
   local overdue = 0
   local next_due, next_due_date, next_desc