goSpaceError syntax hilighting very slow on long lines

[chkno]

This rule is slow on long lines:

syn match goSpaceError display "\(\(^\|[={(,;]\)\s*<-\)\@<=\s\+"

To reproduce:

1. Begin editing a new file foo.vim.
2. Create 5000 spaces (5000i<space><esc>)
3. Attempt to add a 5001th space or otherwise attempt to edit this line. Every UI interaction incurs a ~10s lag.

Output from ":syntime report":

 TOTAL      COUNT  MATCH   SLOWEST     AVERAGE   NAME               PATTERN
19.232237   2      0      10.416958    9.616119  goSpaceError       \(\(^\|[={(,;]\)\s*<
 0.021542   2      0       0.011089    0.010771  goSpaceError       \(\<chan\)\@<=\s\+\(
 0.017746   2      0       0.008958    0.008873  goSpaceError       \(<-\)\@<=\s\+\(chan
...

[fatih]

Hi @chkno , I'm aware of it, that's why it's disabled by default. If you disable it:

let g:go_highlight_space_tab_error = 0
let g:go_highlight_array_whitespace_error = 0
let g:go_highlight_trailing_whitespace_error = 0

You are good to go. Unfortunately I don't have time to tackle the syntax file. Also I have some settings which speeds up the highlighting a little more:

" speed up syntax highlighting
set nocursorcolumn
set nocursorline
syntax sync minlines=256
set synmaxcol=300
set re=1

Does this improve your situation?

[fatih]

Any response on this?

[fatih]

Closing as I didn't get a response for over 1 month.