Problem: completion: selected item not cleared on backspace when
'autocomplete' is set
Solution: Clear the selected item (Girish Palya)
closes: #18260
Signed-off-by: Girish Palya <girishji@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
Add minimal reference to LSP. It might help new users.
closes: #18276
Signed-off-by: Girish Palya <girishji@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
Manual completion can still be used when 'autocomplete' is set, so
saying "active" is better than "enabled".
closes: #18261
Signed-off-by: zeertzjq <zeertzjq@outlook.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
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: #18213
Signed-off-by: Girish Palya <girishji@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
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: #17960
Signed-off-by: Girish Palya <girishji@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
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: #17812
Signed-off-by: Girish Palya <girishji@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
Problem: close button "X" is visible in the non-GUI 'tabline', even
when the mouse is disabled
Solution: only show the button when 'mouse' contains any of the flags
"anvi" (Girish Palya)
The tabline always displays an "X" (close) button, and the info popup
shows both a close button and a resize handle—even when the mouse is
disabled. These UI elements are only actionable with the mouse and serve
no purpose for keyboard users who disable the mouse. Displaying
non-functional, clickable elements in a non-GUI environment is
misleading and adds unnecessary visual clutter.
So remove the close button and resize handle when the mouse is disabled.
They appear again when mouse is enabled.
closes: #17765
Signed-off-by: Girish Palya <girishji@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
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: #17651
Signed-off-by: Girish Palya <girishji@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
Before this commit, I had trouble finding information about configuring
the insert mode completion. In particular, it was not clear that the
'wildopt' config that I already had in my vimrc does not apply here.
Also, `insert.txt` barely mentioned 'completeopt' except when
describing popups (I was more interested in bash-like behavior
where the unique prefix of all completions is completed first).
I'm hoping these edits will make the relevant docs easier to find.
closes: #17515
Signed-off-by: Ilya Grigoriev <ilyagr@users.noreply.github.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
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: #17395
Signed-off-by: glepnir <glephunter@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
Problem: not easily possible to complete from register content
Solution: add register-completion submode using i_CTRL-X_CTRL-R
(glepnir)
closes: #17354
Signed-off-by: glepnir <glephunter@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
Problem: Currently, 'smartcase' is respected when completing keywords
using <C-N>, <C-P>, <C-X><C-N>, and <C-X><C-P>. However, when
a user continues typing and the completion menu is filtered
using cached matches, 'smartcase' is not applied. This leads
to poor-quality or irrelevant completion suggestions, as shown
in the example below.
Solution: When filtering cached completion items after typing additional
characters, apply case-sensitive comparison if 'smartcase' is
enabled and the typed pattern includes uppercase characters.
This ensures consistent and expected completion behavior.
(Girish Palya)
closes: #17271
Signed-off-by: Girish Palya <girishji@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
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: #17065
Co-authored-by: Christian Brabandt <cb@256bit.org>
Co-authored-by: zeertzjq <zeertzjq@outlook.com>
Co-authored-by: glepnir <glephunter@gmail.com>
Signed-off-by: Girish Palya <girishji@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
Problem: Test for patch 9.1.1186 doesn't fail without the patch.
Solution: Set 'nomodeline' in the test (zeertzjq).
closes: #16835
Signed-off-by: zeertzjq <zeertzjq@outlook.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
Problem: not able to get the displayed items in complete_info()
(Evgeni Chasnovski)
Solution: return the visible items via the "matches" key for
complete_info() (glepnir)
fixes: #10007closes: #16307
Signed-off-by: glepnir <glephunter@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
Problem: Currently completion attribute hl_group is combined with
all items, which is redundant and confusing with kind_hlgroup
Solution: Renamed to abbr_hlgroup and combine it only with the abbr item
(glepnir).
closes: #15818
Signed-off-by: glepnir <glephunter@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
Problem: cannot set special highlight kind in popupmenu
Solution: add kind_hlgroup item to complete function
(glepnir)
closes: #15561
Signed-off-by: glepnir <glephunter@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
Problem: Rename of pum hl_group is incomplete in source.
Solution: Also rename the test function. Rename to user_hlattr in code
to avoid confusion with pum_extra. Add test with matched text
highlighting (zeertzjq).
closes: #15348
Signed-off-by: zeertzjq <zeertzjq@outlook.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
Problem: cannot mark deprecated attributes in completion menu
Solution: add hl_group to the Dictionary of supported completion fields
(glepnir)
closes: #15314
Signed-off-by: glepnir <glephunter@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
Problem: i_CTRL-R- no longer works in replace mode
Solution: delete characters in replace mode before putting, add a test,
add a bit warning into the documentation, that i_CTRL-R-P/O
is not supported in Replace mode for now
fixes: #13792closes: #13816
Signed-off-by: Christian Brabandt <cb@256bit.org>
