Wsrtjtyk

I want the vim to call ':!gn format BUILD.gn' when I write BUILD.gn file, my .vimrc is (version 1)

autocmd BufWritePre  *.{gn,gni} call GnFormat()

function! GnForamt()

  exec '!gn format %'

endfunction

But it can not work when I press ':w", it shows error message as

Error detected while processing BufWrite Autocommands for "*.gn":

"BUILD.gn" 67L, 1423C written

How to show more detail debug information and what's the correct method to call external format tool?

I also tried following method, but failed too (version 2)

autocmd BufWritePre  *.{gn,gni} call GnFormat()

function! GnForamt()

  exec '%!gn format --stdin'

endfunction

The output result of version 2 .vimrc of :11verbose w is

Executing BufWrite Autocommands for "*.{gn,gni}"

autocommand call GnFormat()

Error detected while processing BufWrite Autocommands for "*.{gn,gni}":

"BUILD.gn" 27L, 538C written

Executing BufWritePost Autocommands for "*"

autocommand cal s:record(expand('<abuf>', 1))

Executing BufWritePost Autocommands for "*"

autocommand call s:BufWritePostHook(expand('<afile>', 1))

And in the version 2, I can use :call GnForamt() manually to reformat the buffer without any error message.

Just know the reason

autocmd BufWritePre  *.{gn,gni} call GnFormat()

function! GnFormat()   " <--- typo of Format as Foramt

  exec '%!gn format --stdin'

endfunction

try :debug w (see :h debug) or :13verbose w. See :h verbose and :h 'verbose'.

:[level]verbose will allow you to activate verbose mode for a single action