feat(commands): command-line completion for Goto/Colorize/tag commands (P3)

Upstream attaches -complete= to several commands; nuwiki had none, so <Tab>
at the : line never completed page/tag/colour names. New
autoload/nuwiki/complete.vim adds pure client-side, synchronous completers
(config + filesystem, never the LSP — so they work under vim-lsp, coc and
Neovim), wired via -complete=customlist into all command contexts:

- nuwiki#complete#pages → VimwikiGoto/NuwikiGoto (glob wiki roots for page names)
- nuwiki#complete#colors → VimwikiColorize/NuwikiColorize (color_dic keys +
  colours already used in buffer color:… spans)
- nuwiki#complete#tags → VimwikiSearchTags/GenerateTagLinks/GenerateTags (+Nuwiki)
  (scan wiki files for :tag: runs — the tag index is server-side and a
  synchronous completer can't query it, so we read the same source it indexes)

Documented divergence: no file completer for VimwikiRenameFile — nuwiki
delegates renaming to the LSP rename request (no filename arg to complete),
unlike upstream which renames itself.

Tests: complete.{pages_globs_and_filters,tags_scans_wiki_files,
colors_from_buffer_spans} (test-keymaps-vim.vim). Both harnesses green.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

autoload/nuwiki/complete.vim

@@ -0,0 +1,86 @@
+" autoload/nuwiki/complete.vim — command-line completion for the
+" :Vimwiki*/:Nuwiki* commands (mirrors upstream vimwiki's -complete= specs).
+"
+" Pure client-side and synchronous: candidates come from config and the
+" filesystem, never the LSP, so a `-complete=customlist,{fn}` attribute can
+" call these directly under vim-lsp, coc, and Neovim alike.
+"
+" NOTE on files/RenameFile: upstream's :VimwikiRenameFile takes a new-name arg
+" with file completion because upstream performs the rename itself. nuwiki
+" delegates renaming to the LSP rename request (`:LspRename` / coc `rename`),
+" which drives its own interactive prompt — there is no filename argument to
+" complete, so no file completer is provided (documented divergence).
+
+" Page-name completion (VimwikiGoto). Globs every configured wiki root for its
+" `*<ext>` files and returns their root-relative names with the extension
+" stripped, filtered by {arglead}. Mirrors upstream complete_links_raw.
+function! nuwiki#complete#pages(arglead, cmdline, cursorpos) abort
+  let l:names = {}
+  for l:w in nuwiki#commands#wiki_list()
+    let l:root = substitute(get(l:w, 'root', ''), '/\+$', '', '')
+    if l:root ==# '' | continue | endif
+    let l:ext = get(l:w, 'ext', '.wiki')
+    for l:f in glob(l:root . '/**/*' . l:ext, 0, 1)
+      let l:rel = l:f[len(l:root) + 1 :]
+      if l:rel ==# '' | continue | endif
+      let l:rel = l:rel[: -len(l:ext) - 1]
+      let l:names[l:rel] = 1
+    endfor
+  endfor
+  return filter(sort(keys(l:names)), 'stridx(v:val, a:arglead) == 0')
+endfunction
+
+" Colour completion (VimwikiColorize) — keys from any configured `color_dic`
+" (per-wiki `g:nuwiki_wikis[].color_dic` or the scalar `g:nuwiki_color_dic`)
+" plus colours already used in `color:NAME` spans in the current buffer.
+function! nuwiki#complete#colors(arglead, cmdline, cursorpos) abort
+  let l:set = {}
+  for l:w in get(g:, 'nuwiki_wikis', [])
+    for l:k in keys(get(l:w, 'color_dic', {}))
+      let l:set[l:k] = 1
+    endfor
+  endfor
+  for l:k in keys(get(g:, 'nuwiki_color_dic', {}))
+    let l:set[l:k] = 1
+  endfor
+  for l:line in getline(1, '$')
+    let l:start = 0
+    while 1
+      let l:m = matchstrpos(l:line, 'color:\s*\zs[^"'';)]\+', l:start)
+      if l:m[1] < 0 | break | endif
+      let l:set[trim(l:m[0])] = 1
+      let l:start = l:m[2]
+    endwhile
+  endfor
+  return filter(sort(keys(l:set)), 'stridx(v:val, a:arglead) == 0')
+endfunction
+
+" Tag completion (VimwikiSearchTags / VimwikiGenerateTagLinks). The tag index
+" lives in the LSP server, which a synchronous completer can't query, so we
+" harvest `:tag:` tokens by scanning the configured wikis' files directly —
+" the same source the server indexes. Runs only on <Tab> at the `:` line.
+function! nuwiki#complete#tags(arglead, cmdline, cursorpos) abort
+  let l:set = {}
+  for l:w in nuwiki#commands#wiki_list()
+    let l:root = substitute(get(l:w, 'root', ''), '/\+$', '', '')
+    if l:root ==# '' | continue | endif
+    let l:ext = get(l:w, 'ext', '.wiki')
+    for l:f in glob(l:root . '/**/*' . l:ext, 0, 1)
+      for l:line in readfile(l:f)
+        " Tags come in colon-delimited runs like `:foo:bar:` (no spaces).
+        " Match a whole run, then split out each tag (adjacent tags share a
+        " colon, so a per-tag scan would miss every other one).
+        let l:start = 0
+        while 1
+          let l:m = matchstrpos(l:line, ':\%([^:[:space:]]\+:\)\+', l:start)
+          if l:m[1] < 0 | break | endif
+          for l:t in split(l:m[0], ':')
+            if l:t !=# '' | let l:set[l:t] = 1 | endif
+          endfor
+          let l:start = l:m[2]
+        endwhile
+      endfor
+    endfor
+  endfor
+  return filter(sort(keys(l:set)), 'stridx(v:val, a:arglead) == 0')
+endfunction

development/tests/test-keymaps-vim.vim

@@ -689,6 +689,44 @@ call s:record(
       \ 'cmd.VimwikiSplitLink_accepts_args',
       \ 'err=' . s:sl_err)
 
+" ===== Command-line completion (nuwiki#complete#*) =====
+" Pure client-side completers backing the -complete= specs on VimwikiGoto
+" (pages), VimwikiColorize (colours), and the tag commands. Driven directly
+" (no LSP) against a throwaway wiki dir.
+let s:cw = tempname()
+call mkdir(s:cw, 'p')
+call writefile(['= alpha =', 'tagged :foo:bar:'], s:cw . '/alpha.wiki')
+call writefile(['= beta ='], s:cw . '/beta.wiki')
+let s:save_root = get(g:, 'nuwiki_wiki_root', v:null)
+let g:nuwiki_wiki_root = s:cw
+
+let s:pg = nuwiki#complete#pages('a', '', 0)
+call s:record(
+      \ (index(s:pg, 'alpha') >= 0 && index(s:pg, 'beta') < 0) ? 1 : 0,
+      \ 'complete.pages_globs_and_filters',
+      \ 'got ' . string(s:pg))
+
+let s:tg = nuwiki#complete#tags('', '', 0)
+call s:record(
+      \ (index(s:tg, 'foo') >= 0 && index(s:tg, 'bar') >= 0) ? 1 : 0,
+      \ 'complete.tags_scans_wiki_files',
+      \ 'got ' . string(s:tg))
+
+if s:save_root is v:null
+  unlet g:nuwiki_wiki_root
+else
+  let g:nuwiki_wiki_root = s:save_root
+endif
+call delete(s:cw, 'rf')
+
+" Colours come from `color:NAME` spans already in the buffer.
+call s:set_buf(['<span style="color:tomato">x</span> plain'])
+let s:cl = nuwiki#complete#colors('t', '', 0)
+call s:record(
+      \ index(s:cl, 'tomato') >= 0 ? 1 : 0,
+      \ 'complete.colors_from_buffer_spans',
+      \ 'got ' . string(s:cl))
+
 " ===== Wrap up =====
 
 call add(s:results, '')

development/vimwiki-gap.md

@@ -270,11 +270,26 @@ fix site.
   half is done: all four defs now use upstream's `-count=0` instead of bare
   `-count`; `wiki_index`/`wiki_tab_index` already map the count to the wiki
   number.)_
-- [ ] **No `-complete=` specs** _(new)_ — upstream attaches command-line completion
+- [x] **`-complete=` specs** _(new; done 2026-05-31 command-attribute pass)_ —
-  to `VimwikiGoto` (links), `VimwikiRenameFile` (files), `VimwikiColorize`
+  upstream attaches command-line completion to several commands; nuwiki had
-  (colours), and the tag commands. nuwiki defines none, so `<Tab>` completion of
+  none, so `<Tab>` at the `:` line never completed page / tag / colour names.
-  page / tag / colour names at the `:` line is unavailable. _Fix:_
+  _Fix:_ new `autoload/nuwiki/complete.vim` with pure client-side, synchronous
-  `ftplugin/vimwiki.vim` (both branches) — VimL completers or LSP-backed.
+  completers (config + filesystem, never the LSP, so they work under vim-lsp,
+  coc and Neovim alike), wired via `-complete=customlist,…` into all branches:
+  - `nuwiki#complete#pages` → `VimwikiGoto`/`NuwikiGoto` (globs every wiki
+    root's `*<ext>` files → root-relative page names).
+  - `nuwiki#complete#colors` → `VimwikiColorize`/`NuwikiColorize` (keys from a
+    configured `color_dic` + colours already used in buffer `color:…` spans).
+  - `nuwiki#complete#tags` → `VimwikiSearchTags`/`GenerateTagLinks`/
+    `GenerateTags` (+ Nuwiki forms) — scans the wikis' files for `:tag:` runs
+    (the tag index lives in the server, which a synchronous completer can't
+    query; the file scan reads the same source the server indexes).
+  **Divergence (documented):** no file completer for `VimwikiRenameFile` —
+  upstream completes a new-name arg because it renames itself, but nuwiki
+  delegates renaming to the LSP rename request (`:LspRename`/coc), which drives
+  its own prompt and takes no filename argument. Covered by
+  `complete.pages_globs_and_filters`, `complete.tags_scans_wiki_files`,
+  `complete.colors_from_buffer_spans` (`test-keymaps-vim.vim`).
 - [x] **Minor command-attribute gaps** _(new)_ — all now real, not cosmetic:
   `VimwikiNormalizeLink` is `-nargs=?` and with `1` wraps the `'<`/`'>` selection
   (`wrap_visual_as_wikilink`, both clients; the `x`-mode `+` passes it too);

ftplugin/vimwiki.vim

@@ -69,7 +69,7 @@ if !has('nvim')
   command! -buffer        VimwikiBaddLink               call nuwiki#commands#badd_link()
   command! -buffer -nargs=1 VimwikiSearch  lvimgrep /<args>/ **
   command! -buffer -nargs=1 VWS            lvimgrep /<args>/ **
-  command! -buffer -nargs=1 VimwikiGoto   call nuwiki#commands#wiki_goto_page(<q-args>)
+  command! -buffer -nargs=1 -complete=customlist,nuwiki#complete#pages VimwikiGoto   call nuwiki#commands#wiki_goto_page(<q-args>)
 
   command! -buffer        VimwikiDeleteFile    call nuwiki#commands#delete_file()
   command! -buffer        VimwikiDeleteLink    call nuwiki#commands#delete_file()
@@ -105,15 +105,15 @@ if !has('nvim')
   command! -buffer        VimwikiFindOrphans       call nuwiki#commands#find_orphans()
 
   command! -buffer -bang        VimwikiRebuildTags       call nuwiki#commands#tags_rebuild(<bang>0)
-  command! -buffer -nargs=? VimwikiSearchTags        call nuwiki#commands#tags_search(<q-args>)
+  command! -buffer -nargs=? -complete=customlist,nuwiki#complete#tags VimwikiSearchTags        call nuwiki#commands#tags_search(<q-args>)
-  command! -buffer -nargs=? VimwikiGenerateTagLinks  call nuwiki#commands#tags_generate_links(<q-args>)
+  command! -buffer -nargs=? -complete=customlist,nuwiki#complete#tags VimwikiGenerateTagLinks  call nuwiki#commands#tags_generate_links(<q-args>)
-  command! -buffer -nargs=? VimwikiGenerateTags      call nuwiki#commands#tags_generate_links(<q-args>)
+  command! -buffer -nargs=? -complete=customlist,nuwiki#complete#tags VimwikiGenerateTags     call nuwiki#commands#tags_generate_links(<q-args>)
 
   " Tables, colorize, and clipboard paste.
   command! -buffer -nargs=* VimwikiTable             call nuwiki#commands#table_insert(<f-args>)
   command! -buffer        VimwikiTableMoveColumnLeft  call nuwiki#commands#table_move_column_left()
   command! -buffer        VimwikiTableMoveColumnRight call nuwiki#commands#table_move_column_right()
-  command! -buffer -nargs=* -range VimwikiColorize   call nuwiki#commands#colorize(<q-args>, <range>)
+  command! -buffer -nargs=* -range -complete=customlist,nuwiki#complete#colors VimwikiColorize   call nuwiki#commands#colorize(<q-args>, <range>)
   command! -buffer        VimwikiPasteLink           call nuwiki#commands#paste_link()
   command! -buffer        VimwikiPasteUrl            call nuwiki#commands#paste_url()
   command! -buffer        VimwikiCatUrl              call nuwiki#commands#cat_url()
@@ -149,9 +149,9 @@ if !has('nvim')
   command! -buffer -range NuwikiCheckLinks         call nuwiki#commands#check_links(<range>, <line1>, <line2>)
   command! -buffer        NuwikiFindOrphans        call nuwiki#commands#find_orphans()
   command! -buffer -bang        NuwikiRebuildTags        call nuwiki#commands#tags_rebuild(<bang>0)
-  command! -buffer -nargs=? NuwikiSearchTags         call nuwiki#commands#tags_search(<q-args>)
+  command! -buffer -nargs=? -complete=customlist,nuwiki#complete#tags NuwikiSearchTags         call nuwiki#commands#tags_search(<q-args>)
-  command! -buffer -nargs=? NuwikiGenerateTagLinks   call nuwiki#commands#tags_generate_links(<q-args>)
+  command! -buffer -nargs=? -complete=customlist,nuwiki#complete#tags NuwikiGenerateTagLinks   call nuwiki#commands#tags_generate_links(<q-args>)
-  command! -buffer -nargs=1 NuwikiGoto               call nuwiki#commands#wiki_goto_page(<q-args>)
+  command! -buffer -nargs=1 -complete=customlist,nuwiki#complete#pages NuwikiGoto               call nuwiki#commands#wiki_goto_page(<q-args>)
 
   " Canonical :Nuwiki* names that mirror the documented surface.
   " The older :Nuwiki* spellings above stay defined for back-compat.
@@ -185,7 +185,7 @@ if !has('nvim')
   command! -buffer -nargs=* NuwikiTable               call nuwiki#commands#table_insert(<f-args>)
   command! -buffer        NuwikiTableMoveColumnLeft    call nuwiki#commands#table_move_column_left()
   command! -buffer        NuwikiTableMoveColumnRight   call nuwiki#commands#table_move_column_right()
-  command! -buffer -nargs=* -range NuwikiColorize     call nuwiki#commands#colorize(<q-args>, <range>)
+  command! -buffer -nargs=* -range -complete=customlist,nuwiki#complete#colors NuwikiColorize     call nuwiki#commands#colorize(<q-args>, <range>)
   command! -buffer        NuwikiPasteLink              call nuwiki#commands#paste_link()
   command! -buffer        NuwikiPasteUrl               call nuwiki#commands#paste_url()
   command! -buffer        NuwikiCatUrl                 call nuwiki#commands#cat_url()
@@ -412,7 +412,7 @@ command! -buffer        VimwikiTabDropLink lua require('nuwiki.commands').follow
 command! -buffer        VimwikiNextLink    lua require('nuwiki.commands').link_next()
 command! -buffer        VimwikiPrevLink    lua require('nuwiki.commands').link_prev()
 command! -buffer        VimwikiBaddLink    lua require('nuwiki.commands').badd_link()
-command! -buffer -nargs=1 VimwikiGoto       lua require('nuwiki.commands').wiki_goto_page(<q-args>)
+command! -buffer -nargs=1 -complete=customlist,nuwiki#complete#pages VimwikiGoto       lua require('nuwiki.commands').wiki_goto_page(<q-args>)
 command! -buffer        VimwikiBacklinks   lua vim.lsp.buf.references()
 command! -buffer        VWB                lua vim.lsp.buf.references()
 command! -buffer -nargs=1 VimwikiSearch     lvimgrep /<args>/ **
@@ -453,15 +453,15 @@ command! -buffer -range VimwikiCheckLinks        lua require('nuwiki.commands').
 command! -buffer        VimwikiFindOrphans       lua require('nuwiki.commands').find_orphans()
 
 command! -buffer -bang        VimwikiRebuildTags       lua require('nuwiki.commands').tags_rebuild('<bang>' == '!')
-command! -buffer -nargs=? VimwikiSearchTags        lua require('nuwiki.commands').tags_search(<q-args>)
+command! -buffer -nargs=? -complete=customlist,nuwiki#complete#tags VimwikiSearchTags        lua require('nuwiki.commands').tags_search(<q-args>)
-command! -buffer -nargs=? VimwikiGenerateTagLinks  lua require('nuwiki.commands').tags_generate_links(<q-args>)
+command! -buffer -nargs=? -complete=customlist,nuwiki#complete#tags VimwikiGenerateTagLinks  lua require('nuwiki.commands').tags_generate_links(<q-args>)
-command! -buffer -nargs=? VimwikiGenerateTags      lua require('nuwiki.commands').tags_generate_links(<q-args>)
+command! -buffer -nargs=? -complete=customlist,nuwiki#complete#tags VimwikiGenerateTags     lua require('nuwiki.commands').tags_generate_links(<q-args>)
 
 " Tables, colorize, and clipboard paste.
 command! -buffer -nargs=* VimwikiTable             lua require('nuwiki.commands').table_insert(<f-args>)
 command! -buffer        VimwikiTableMoveColumnLeft  lua require('nuwiki.commands').table_move_column_left()
 command! -buffer        VimwikiTableMoveColumnRight lua require('nuwiki.commands').table_move_column_right()
-command! -buffer -nargs=* -range VimwikiColorize   lua require('nuwiki.commands').colorize(<q-args>, <range> > 0)
+command! -buffer -nargs=* -range -complete=customlist,nuwiki#complete#colors VimwikiColorize   lua require('nuwiki.commands').colorize(<q-args>, <range> > 0)
 command! -buffer        VimwikiPasteLink           lua require('nuwiki.commands').paste_link()
 command! -buffer        VimwikiPasteUrl            lua require('nuwiki.commands').paste_url()
 command! -buffer        VimwikiCatUrl              lua require('nuwiki.commands').cat_url()
@@ -493,9 +493,9 @@ command! -buffer        NuwikiGenerateLinks      lua require('nuwiki.commands').
 command! -buffer -range NuwikiCheckLinks         lua require('nuwiki.commands').check_links(<range>, <line1>, <line2>)
 command! -buffer        NuwikiFindOrphans        lua require('nuwiki.commands').find_orphans()
 command! -buffer -bang        NuwikiRebuildTags        lua require('nuwiki.commands').tags_rebuild('<bang>' == '!')
-command! -buffer -nargs=? NuwikiSearchTags         lua require('nuwiki.commands').tags_search(<q-args>)
+command! -buffer -nargs=? -complete=customlist,nuwiki#complete#tags NuwikiSearchTags         lua require('nuwiki.commands').tags_search(<q-args>)
-command! -buffer -nargs=? NuwikiGenerateTagLinks   lua require('nuwiki.commands').tags_generate_links(<q-args>)
+command! -buffer -nargs=? -complete=customlist,nuwiki#complete#tags NuwikiGenerateTagLinks   lua require('nuwiki.commands').tags_generate_links(<q-args>)
-command! -buffer -nargs=1 NuwikiGoto               lua require('nuwiki.commands').wiki_goto_page(<q-args>)
+command! -buffer -nargs=1 -complete=customlist,nuwiki#complete#pages NuwikiGoto               lua require('nuwiki.commands').wiki_goto_page(<q-args>)
 
 " Canonical :Nuwiki* names that mirror the documented surface.
 " The older :Nuwiki* spellings above stay defined for back-compat.
@@ -533,7 +533,7 @@ command! -buffer        NuwikiTableAlign             lua require('nuwiki.command
 command! -buffer -nargs=* NuwikiTable               lua require('nuwiki.commands').table_insert(<f-args>)
 command! -buffer        NuwikiTableMoveColumnLeft    lua require('nuwiki.commands').table_move_column_left()
 command! -buffer        NuwikiTableMoveColumnRight   lua require('nuwiki.commands').table_move_column_right()
-command! -buffer -nargs=* -range NuwikiColorize     lua require('nuwiki.commands').colorize(<q-args>, <range> > 0)
+command! -buffer -nargs=* -range -complete=customlist,nuwiki#complete#colors NuwikiColorize     lua require('nuwiki.commands').colorize(<q-args>, <range> > 0)
 command! -buffer        NuwikiPasteLink              lua require('nuwiki.commands').paste_link()
 command! -buffer        NuwikiPasteUrl               lua require('nuwiki.commands').paste_url()
 command! -buffer        NuwikiCatUrl                 lua require('nuwiki.commands').cat_url()