Problem: completion: "longest" doesn't work for manual completion when
'autocomplete' is on (after 9.1.1800).
Solution: Only reset compl_get_longest when enabling autocompletion
(zeertzjq).
closes: vim/vim#18430b3966d6a8e
Problem: completion: autocompletion can be improved
Solution: Add support for "longest" and "preinsert" in 'autocomplete';
add preinserted() (Girish Palya)
* Add support for "longest" in 'completeopt' when 'autocomplete'
is enabled. (Note: the cursor position does not change automatically
when 'autocomplete' is enabled.)
* Add support for "preinsert" when 'autocomplete' is enabled. Ensure
"preinsert" works the same with and without 'autocomplete'
* introduce the preinserted() Vim script function, useful for defining
custom key mappings.
fixes: vim/vim#18314closes: vim/vim#18387c05335082a
Co-authored-by: Girish Palya <girishji@gmail.com>
Problem: completion: 'autocomplete' cannot be enabled per buffer
(Tomasz N)
Solution: Make 'autocomplete' global or local to buffer (Girish Palya)
fixes: vim/vim#18320closes: vim/vim#183330208b3e80a
Co-authored-by: Girish Palya <girishji@gmail.com>
Problem: "adding" expansion doesn't work with cfc=keyword.
Solution: Remove incorrect assignment to compl_cont_status. Don't use
fuzzy collection in "adding" status (zeertzjq).
related: neovim/neovim#35842closes: vim/vim#18351e19a882ffc
Problem: complete: some redraw issues with 'autocomplete'
Solution: Fix the issues (Girish Palya)
This commit contains the following changes:
* Fix that wildtrigger() might leave opened popupmenu around vim/vim#18298
* Remove blinking message on the command line when a menu item from a loaded
buffer is selected during 'autocomplete'
* Add a test for PR vim/vim#18265 to demonstrate why the PR is required for correct
'autocomplete' behavior
fixes: vim/vim#18298closes: vim/vim#18328ee9a2f0512
Co-authored-by: Girish Palya <girishji@gmail.com>
Problem: completion: selected item not cleared on backspace when
'autocomplete' is set
Solution: Clear the selected item (Girish Palya)
closes: vim/vim#182605c9b71d63c
Co-authored-by: Girish Palya <girishji@gmail.com>
Problem: tests: No test when deleting text after autocompletion with preinsert
did complete an entry
Solution: Verify, that after deletion autocompletion does not reinsert
the deleted text. Note: the actual issue was fixed with v9.1.1750.
(Girish Palya)
Pre v9.1.1750 behaviour:
When autocomplete is enabled with *preinsert*, deleting text after selecting a
longer match could cause unintended reinsertion, e.g.:
- Matches available: "foo" and "foobar".
- User selects "foobar" with Ctrl-N
- User deletes characters back to "foo".
- Autocomplete then incorrectly re-inserts "bar", preventing deletion past "foo".
v9.1.1750 removes the unwanted reinsertion so text can be deleted correctly.
closes: vim/vim#18259fe0061c609
Co-authored-by: Girish Palya <girishji@gmail.com>
Problem: completion: redo (.) broken with preinsert and autocompletion
Solution: Make redo (.) work with preinsert and autocompletion
(Girish Palya)
closes: vim/vim#18253306a138172
Co-authored-by: Girish Palya <girishji@gmail.com>
Problem: complete: preinsert does not work well with preinsert
Solution: Make "preinsert" completeopt value work with autocompletion
(Girish Palya)
This change extends Insert mode autocompletion so that 'preinsert' also
works when 'autocomplete' is enabled.
Try: `:set ac cot=preinsert`
See `:help 'cot'` for more details.
closes: vim/vim#18213fa6fd41a94
Co-authored-by: Girish Palya <girishji@gmail.com>
Problem:
insert-mode ctrl-r input is treated like raw user input, which is almost
never useful. This means any newlines in the input are affected by
autoindent, etc., which is:
- slow
- usually breaks the formatting of the input
Solution:
- ctrl-r should be treated like a paste, not user-input.
- does not affect `<c-r>=`, so `<c-r>=@x` can still be used to get the
old behavior.
Co-authored-by: Justin M. Keyes <justinkz@gmail.com>
Co-authored-by: zeertzjq <zeertzjq@outlook.com>
Problem: tests: no test for actually moving cursor when menu is not
open with 'autocompletedelay'.
Solution: Use <Up> first in the test. Also remove two unnecessary <Esc>s
in completion timeout test (zeertzjq).
closes: vim/vim#18097e8b99ff6d5
Problem: completion: not possible to delay the autcompletion
Solution: add the 'autocompletedelay' option value (Girish Palya).
This patch introduces a new global option 'autocompletedelay'/'acl' that
specifies the delay, in milliseconds, before the autocomplete menu
appears after typing.
When set to a non-zero value, Vim waits for the specified time before
showing the completion popup, allowing users to reduce distraction from
rapid suggestion pop-ups or to fine-tune the responsiveness of
completion.
The default value is 0, which preserves the current immediate-popup
behavior.
closes: vim/vim#17960a09b1604d4
N/A patch: vim-patch:9.1.1641: a few compiler warnings are output
Co-authored-by: Girish Palya <girishji@gmail.com>
Problem: Incorrect E535 error message (after 9.1.1603).
Solution: Don't use transchar(), as the character is always printable
(zeertzjq).
closes: vim/vim#17948b362995430
Problem: completion: incorrect selected index returned from
complete_info()
Solution: Return the index into "items" and restore the previous
behaviour (Robert Muir).
complete_info() returned an incorrect selected index after
0ac1eb3555445f4c458c06cef7c411de1c8d1020 (Patch v9.1.1311). Effectively
it became an index into "matches" instead of "items". Return the index
into "items" by default to restore the previous behavior, unless
"matches" was requested.
closes: vim/vim#179528e2a229189
Co-authored-by: Robert Muir <rmuir@apache.org>
Co-authored-by: Hirohito Higashi <h.east.727@gmail.com>
Problem: completion: cannot use autoloaded funcs in 'complete' F{func}
(Maxim Kim)
Solution: Make it work (Girish Palya)
fixes: vim/vim#17869closes: vim/vim#178851bfe86a7d3
Cherry-pick Test_omni_autoload() from patch 8.2.3223.
Co-authored-by: Girish Palya <girishji@gmail.com>
Problem: completion: hang (after 9.1.1471) or E684 (after 9.1.1410)
when 'tagfunc' calls complete().
Solution: Check if complete() has been called immediately after getting
matches instead of in the next loop iteration (zeertzjq).
related: vim/vim#1668
related: neovim/neovim#34416
related: neovim/neovim#35163closes: vim/vim#17929982cda6976
Problem: cannot perform autocompletion
Solution: Add the 'autocomplete' option value
(Girish Palya)
This change introduces the 'autocomplete' ('ac') boolean option to
enable automatic popup menu completion during insert mode. When enabled,
Vim shows a completion menu as you type, similar to pressing |i\_CTRL-N|
manually. The items are collected from sources defined in the
'complete' option.
To ensure responsiveness, this feature uses a time-sliced strategy:
- Sources earlier in the 'complete' list are given more time.
- If a source exceeds its allocated timeout, it is interrupted.
- The next source is then started with a reduced timeout (exponentially
decayed).
- A small minimum ensures every source still gets a brief chance to
contribute.
The feature is fully compatible with other |i_CTRL-X| completion modes,
which can temporarily suspend automatic completion when triggered.
See :help 'autocomplete' and :help ins-autocompletion for more details.
To try it out, use :set ac
You should see a popup menu appear automatically with suggestions. This
works seamlessly across:
- Large files (multi-gigabyte size)
- Massive codebases (:argadd thousands of .c or .h files)
- Large dictionaries via the `k` option
- Slow or blocking LSP servers or user-defined 'completefunc'
Despite potential slowness in sources, the menu remains fast,
responsive, and useful.
Compatibility: This mode is fully compatible with existing completion
methods. You can still invoke any CTRL-X based completion (e.g.,
CTRL-X CTRL-F for filenames) at any time (CTRL-X temporarily
suspends 'autocomplete'). To specifically use i_CTRL-N, dismiss the
current popup by pressing CTRL-E first.
---
How it works
To keep completion snappy under all conditions, autocompletion uses a
decaying time-sliced algorithm:
- Starts with an initial timeout (80ms).
- If a source does not complete within the timeout, it's interrupted and
the timeout is halved for the next source.
- This continues recursively until a minimum timeout (5ms) is reached.
- All sources are given a chance, but slower ones are de-prioritized
quickly.
Most of the time, matches are computed well within the initial window.
---
Implementation details
- Completion logic is mostly triggered in `edit.c` and handled in
insexpand.c.
- Uses existing inc_compl_check_keys() mechanism, so no new polling
hooks are needed.
- The completion system already checks for user input periodically; it
now also checks for timer expiry.
---
Design notes
- The menu doesn't continuously update after it's shown to prevent
visual distraction (due to resizing) and ensure the internal list
stays synchronized with the displayed menu.
- The 'complete' option determines priority—sources listed earlier get
more time.
- The exponential time-decay mechanism prevents indefinite collection,
contributing to low CPU usage and a minimal memory footprint.
- Timeout values are intentionally not configurable—this system is
optimized to "just work" out of the box. If autocompletion feels slow,
it typically indicates a deeper performance bottleneck (e.g., a slow
custom function not using `complete_check()`) rather than a
configuration issue.
---
Performance
Based on testing, the total roundtrip time for completion is generally
under 200ms. For common usage, it often responds in under 50ms on an
average laptop, which falls within the "feels instantaneous" category
(sub-100ms) for perceived user experience.
| Upper Bound (ms) | Perceived UX
|----------------- |-------------
| <100 ms | Excellent; instantaneous
| <200 ms | Good; snappy
| >300 ms | Noticeable lag
| >500 ms | Sluggish/Broken
---
Why this belongs in core:
- Minimal and focused implementation, tightly integrated with existing
Insert-mode completion logic.
- Zero reliance on autocommands and external scripting.
- Makes full use of Vim’s highly composable 'complete' infrastructure
while avoiding the complexity of plugin-based solutions.
- Gives users C native autocompletion with excellent responsiveness and
no configuration overhead.
- Adds a key UX functionality in a simple, performant, and Vim-like way.
closes: vim/vim#17812af9a7a04f1
Co-authored-by: Girish Palya <girishji@gmail.com>
Problem: completion: messages don't respect 'shm' setting
Solution: Turn off completion messages when 'shortmess' includes "c"
(Girish Palya).
`:set shortmess+=c` is intended to reduce noise during completion by
suppressing messages.
Previously, some completion messages still appeared regardless of this setting.
This change ensures that **all** completion-related messages are suppressed
when `'c'` is present in `'shortmess'`.
Not entirely sure if the original behavior was intentional. If there's a
reason certain messages were always shown, feel free to close this without
merging.
closes: vim/vim#17737fe1d3c8af7
Co-authored-by: Girish Palya <girishji@gmail.com>
Problem: completion: can only complete from keyword characters
Solution: remove this restriction, allow completion functions when
called from i_CTRL-N/i_CTRL-P to be triggered from non-keyword
characters (Girish Palya)
Previously, functions specified in the `'complete'` option were
restricted to starting completion only from keyword characters (as
introduced in PR 17065). This change removes that restriction.
With this change, user-defined functions (e.g., `omnifunc`, `userfunc`)
used in `'complete'` can now initiate completion even when triggered
from non-keyword characters. This makes it easier to reuse existing
functions alongside other sources without having to consider whether the
cursor is on a keyword or non-keyword character, or worry about where
the replacement should begin (i.e., the `findstart=1` return value).
The logic for both the “collection” and “filtering” phases now fully
respects each source’s specified start column. This also extends to
fuzzy matching, making completions more predictable.
Internally, this builds on previously merged infrastructure that tracks
per-source metadata. This PR focuses on applying that metadata to
compute the leader string and insertion text appropriately for each
match.
Also, a memory corruption has been fixed in prepare_cpt_compl_funcs().
closes: vim/vim#17651ba11e78f1d
Co-authored-by: Girish Palya <girishji@gmail.com>
Problem: completion: Functions specified in the 'complete' option did
not have the leader string removed when called with findstart = 0,
unlike 'omnifunc' behavior
Solution: update behaviour and make behaviour consistent (Girish Palya)
closes: vim/vim#17636fa16c7ab3f
Co-authored-by: Girish Palya <girishji@gmail.com>
Problem: completion: code can be improved
Solution: remove reposition_match() and use mergesort_list(),
for fuzzy completion, sort by fuzzy score immediately after
setting a new leader (Girish Palya)
closes: vim/vim#17460b8ee1cf56e
Co-authored-by: Girish Palya <girishji@gmail.com>
Co-authored-by: glepnir <glephunter@gmail.com>
Problem: completion: various flaws in fuzzy completion
Solution: fix the issues (Girish Palya)
- Remove the brittle `qsort()` on `compl_match_array`.
- Add a stable, non-recursive `mergesort` for the internal doubly
linked list of matches.
- The sort now happens directly on the internal representation (`compl_T`),
preserving sync with external structures and making sorting stable.
- Update fuzzy match logic to enforce `max_matches` limits after
sorting.
- Remove `trim_compl_match_array()`, which is no longer necessary.
- Fixe test failures by correctly setting `selected` index and
maintaining match consistency.
- Introduce `mergesort_list()` in `misc2.c`, which operates generically
over doubly linked lists.
- Remove `pum_score` and `pum_idx` variables
fixes: vim/vim#17387closes: vim/vim#174308cd42a58b4
Co-authored-by: Girish Palya <girishji@gmail.com>
Problem: CTRL-X CTRL-R only completes individual words from registers,
making it difficult to insert complete register content.
Solution: Add consecutive CTRL-X CTRL-R support - first press completes
words, second press completes full register lines, similar to
CTRL-X CTRL-L and CTRL-X CTRL-P behavior (glepnir).
closes: vim/vim#17395d5fdfa5c9c
Co-authored-by: glepnir <glephunter@gmail.com>
Problem: PMenu selection broken with multi-line selection and limits
(Maxim Kim)
Solution: update completion match index when limiting the completion
sources (Girish Palya)
fixes: vim/vim#17394closes: vim/vim#174016c40df09e0
Co-authored-by: Girish Palya <girishji@gmail.com>
Problem: using f-flag in 'complete' conflicts with Neovims filename
completion (glepnir, after v9.1.1301).
Solution: use upper-case "F" flag for completion functions
(Girish Palya).
fixes: vim/vim#17347closes: vim/vim#1737814f6da5ba8
Co-authored-by: Girish Palya <girishji@gmail.com>
Problem: completion: not possible to limit number of matches
Solution: allow to limit the matches for 'complete' sources by using the
"{flag}^{limit}" notation (Girish Palya)
This change extends the 'complete' option to support limiting the
number of matches returned from individual completion sources.
**Rationale:** In large files, certain sources (such as the current
buffer) can generate an overwhelming number of matches, which may cause
more relevant results from other sources (e.g., LSP or tags) to be
pushed out of view. By specifying per-source match limits, the
completion menu remains balanced and diverse, improving visibility and
relevance of suggestions.
A caret (`^`) followed by a number can be appended to a source flag to
specify the maximum number of matches for that source. For example:
```
:set complete=.^9,w,u,t^5
```
In this configuration:
- The current buffer (`.`) will return up to 9 matches.
- The tag completion (`t`) will return up to 5 matches.
- Other sources (`w`, `u`) are not limited.
This feature is fully backward-compatible and does not affect behavior
when the `^count` suffix is not used.
The caret (`^`) was chosen as the delimiter because it is least likely
to appear in file names.
closes: vim/vim#170870ac1eb3555
Cherry-pick test_options.vim change from patch 9.1.1325.
Co-authored-by: Girish Palya <girishji@gmail.com>
Problem: completion: cannot configure completion functions with
'complete'
Solution: add support for setting completion functions using the f and o
flag for 'complete' (Girish Palya)
This change adds two new values to the `'complete'` (`'cpt'`) option:
- `f` – invokes the function specified by the `'completefunc'` option
- `f{func}` – invokes a specific function `{func}` (can be a string or `Funcref`)
These new flags extend keyword completion behavior (e.g., via `<C-N>` /
`<C-P>`) by allowing function-based sources to participate in standard keyword
completion.
**Key behaviors:**
- Multiple `f{func}` values can be specified, and all will be called in order.
- Functions should follow the interface defined in `:help complete-functions`.
- When using `f{func}`, escaping is required for spaces (with `\`) and commas
(with `\\`) in `Funcref` names.
- If a function sets `'refresh'` to `'always'`, it will be re-invoked on every
change to the input text. Otherwise, Vim will attempt to reuse and filter
existing matches as the input changes, which matches the default behavior of
other completion sources.
- Matches are inserted at the keyword boundary for consistency with other completion methods.
- If finding matches is time-consuming, `complete_check()` can be used to
maintain responsiveness.
- Completion matches are gathered in the sequence defined by the `'cpt'`
option, preserving source priority.
This feature increases flexibility of standard completion mechanism and may
reduce the need for external completion plugins for many users.
**Examples:**
Complete matches from [LSP](https://github.com/yegappan/lsp) client. Notice the use of `refresh: always` and `function()`.
```vim
set cpt+=ffunction("g:LspCompletor"\\,\ [5]). # maxitems = 5
def! g:LspCompletor(maxitems: number, findstart: number, base: string): any
if findstart == 1
return g:LspOmniFunc(findstart, base)
endif
return {words: g:LspOmniFunc(findstart, base)->slice(0, maxitems), refresh: 'always'}
enddef
autocmd VimEnter * g:LspOptionsSet({ autoComplete: false, omniComplete: true })
```
Complete matches from `:iabbrev`.
```vim
set cpt+=fAbbrevCompletor
def! g:AbbrevCompletor(findstart: number, base: string): any
if findstart > 0
var prefix = getline('.')->strpart(0, col('.') - 1)->matchstr('\S\+$')
if prefix->empty()
return -2
endif
return col('.') - prefix->len() - 1
endif
var lines = execute('ia', 'silent!')
if lines =~? gettext('No abbreviation found')
return v:none # Suppresses warning message
endif
var items = []
for line in lines->split("\n")
var m = line->matchlist('\v^i\s+\zs(\S+)\s+(.*)$')
if m->len() > 2 && m[1]->stridx(base) == 0
items->add({ word: m[1], info: m[2], dup: 1 })
endif
endfor
return items->empty() ? v:none :
items->sort((v1, v2) => v1.word < v2.word ? -1 : v1.word ==# v2.word ? 0 : 1)
enddef
```
**Auto-completion:**
Vim's standard completion frequently checks for user input while searching for
new matches. It is responsive irrespective of file size. This makes it
well-suited for smooth auto-completion. You can try with above examples:
```vim
set cot=menuone,popup,noselect inf
autocmd TextChangedI * InsComplete()
def InsComplete()
if getcharstr(1) == '' && getline('.')->strpart(0, col('.') - 1) =~ '\k$'
SkipTextChangedIEvent()
feedkeys("\<c-n>", "n")
endif
enddef
inoremap <silent> <c-e> <c-r>=<SID>SkipTextChangedIEvent()<cr><c-e>
def SkipTextChangedIEvent(): string
# Suppress next event caused by <c-e> (or <c-n> when no matches found)
set eventignore+=TextChangedI
timer_start(1, (_) => {
set eventignore-=TextChangedI
})
return ''
enddef
```
closes: vim/vim#17065cbe53191d0
Temporarily remove bufname completion with #if 0 to make merging easier.
Co-authored-by: Girish Palya <girishji@gmail.com>
Co-authored-by: Christian Brabandt <cb@256bit.org>
Co-authored-by: glepnir <glephunter@gmail.com>
Problem: preview-window does not scroll correctly
Solution: init firstline = 0 for a preview window
(Girish Palya)
The 'info' window, which appears during insert-mode completion to display
additional information, was not scrolling properly when using commands like:
win_execute(popup_findinfo(), "normal! \<PageDown>")
This issue made it impossible to navigate through info window contents using
keyboard-based scrolling.
The fix correctly updates the w_firstline value of the popup window, ensuring
proper scrolling behavior. Mouse scrolling was already working as expected and
remains unaffected.
closes: vim/vim#1670312b1eb58ab
Co-authored-by: Girish Palya <girishji@gmail.com>
Problem: missing info about register completion in complete_info()
(after v9.1.1408)
Solution: update documentation and mention that register is used as
source, add a test (glepnir)
closes: vim/vim#1738949864aecd0
Co-authored-by: glepnir <glephunter@gmail.com>
Problem: not easily possible to complete from register content
Solution: add register-completion submode using i_CTRL-X_CTRL-R
(glepnir)
closes: vim/vim#173540546068aae
Problem: Cannot get completion startcol when space is not the first
trigger character (after v9.1.1383)
Solution: Detect the next comma followed by a space in the option string
and use in next compare loop (glepnir)
closes: vim/vim#1731108db2f4f28
Problem: When a space character is used as a trigger in 'isexpand' option
it doesn't get recognized because skip_to_option_part() skips
spaces after a comma, treating them as option separators
rather than option value (after v9.1.1341)
Solution: manually set the part to a space character (glepnir).
closes: vim/vim#173058d0e42b710
Problem: Cannot return to the original text after selecting the next
item when the currently selected item is the last one.
Solution: When continuing to move down past the last item, locate the
original completion at the head/tail nodes of the completed
linked list (glepnir).
closes: vim/vim#173005a18ccf490
