fix(coc): correct pum col for concealed characters

[fannheyward]

Closes #5582

This fix was made by Codex with GPT-5.4

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 97.91%. Comparing base (31b8b5e) to head (f9398d2).
⚠️ Report is 1 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #5590      +/-   ##
==========================================
- Coverage   97.91%   97.91%   -0.01%     
==========================================
  Files         280      280              
  Lines       27927    27927              
  Branches     5791     5791              
==========================================
- Hits        27346    27344       -2     
  Misses        111      111              
- Partials      470      472       +2     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

[fannheyward]

@A4-Tacks give this a test

[Copilot]

Pull request overview

This PR fixes incorrect popup menu (pum) horizontal positioning when completion happens on lines containing concealed text (and other display-width-affecting characters), addressing issue #5582 by switching to screen-cell–accurate column calculations.

Changes:

• Use screenpos() to compute the pum’s horizontal offset using actual on-screen columns (so conceal/wide chars don’t skew placement).
• Add a fallback path to the prior strdisplaywidth()-based calculation when screenpos() yields invalid positions.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[A4-Tacks]

This doesn't work

[Copilot]

Pull request overview

Copilot reviewed 1 out of 1 changed files in this pull request and generated 3 comments.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[fannheyward]

@A4-Tacks

[A4-Tacks]

This works correctly in set concealcursor=i, but incorrectly in set concealcursor=

Perhaps we should judge &concealcursor =~# 'i'

This fix also caused a misalignment of set nu, seemingly without considering the window edge

[fannheyward]

This works correctly in set concealcursor=i, but incorrectly in set concealcursor=

Perhaps we should judge &concealcursor =~# 'i'

This fix also caused a misalignment of set nu, seemingly without considering the window edge

fixed

[A4-Tacks]

Poor 1 error

Expect

foo f
    foo        [A]
   ________________

Actual

foo f
     foo        [A]
    ________________

[A4-Tacks]

When the line is too long (out of columns), the pum position at the end of the line is incorrect

There are two situations, nowrap and wrap

[fannheyward]

When the line is too long (out of columns), the pum position at the end of the line is incorrect

any screenshot?

[A4-Tacks]

echo $COLUMNS outputs 118

1. Run vim -u mini.vim
2. Input 150a. <esc> I conceal <esc>
3. Input A c

set nowrap:

set wrap:

[A4-Tacks]

It seems that nothing has been fixed in this commit, including the wrap and nowrap

[fannheyward]

mini.vim

set nocompatible
set runtimepath^=~/.local/share/nvim/plugged/coc.nvim
filetype plugin indent on
syntax on
syn match Foo /conceal/ conceal
set conceallevel=2 concealcursor=i

set wrap

set nowrap

[A4-Tacks]

log.zip

2026-04-01_1775015534212.mp4

[A4-Tacks]

Incorrect, what about you?

[fannheyward]

@A4-Tacks should be fixed on wrap/nowrap cases

[A4-Tacks]

Still incorrect, perhaps this is too difficult?

[fannheyward]

The wrap/nowrap cases: if you first input conceal on the begin of the line, then input at the end of the line, the col is incorrect.

If no conceal input at the begin of line first, works as expected.