Automatic rustfmt erases my files sometimes.

[dpc]

• rust.vim version: Current one, I use vim-plug and do :PlugUpdate often.

Steps to reproduce:

I think it started happening when I converted my project to use a workspace. The current state is: crev-dev/cargo-crev@d9fbf06

Expected vs. actual behavior:

Typically my vim consistently reformats a file on every save.

Now, for whatever reason, it stops working in the middle of the session for some files (for which it worked fine just a second ago) and from that time it just keeps erasing them every time I write the buffer. :/

Paste debugging info from the Rust Vim plugin via one of the following
commands: :RustInfo, :RustInfoToClipboard, or :RustInfoToFile <filename>.

rust.vim Global Variables:

let g:ftplugin_rust_source_path = v:null
let g:loaded_syntastic_rust_cargo_checker = v:null
let g:loaded_syntastic_rust_filetype = v:null
let g:loaded_syntastic_rust_rustc_checker = v:null
let g:rust_bang_comment_leader = v:null
let g:rust_cargo_avoid_whole_workspace = v:null
let g:rust_clip_command = v:null
let g:rust_conceal = v:null
let g:rust_conceal_mod_path = v:null
let g:rust_conceal_pub = v:null
let g:rust_fold = v:null
let g:rust_last_args = v:null
let b:rust_last_args = []
let g:rust_last_rustc_args = v:null
let b:rust_last_rustc_args = []
let g:rust_original_delimitMate_excluded_regions = v:null
let g:rust_playpen_url = v:null
let g:rust_prev_delimitMate_quotes = v:null
let g:rust_recent_nearest_cargo_tol = v:null
let g:rust_recent_root_cargo_toml = v:null
let g:rust_recommended_style = v:null
let g:rust_set_conceallevel = v:null
let g:rust_set_conceallevel=1 = v:null
let g:rust_set_foldmethod = v:null
let g:rust_set_foldmethod=1 = v:null
let g:rust_shortener_url = v:null
let g:rustc_makeprg_no_percent = v:null
let g:rustc_path = v:null
let g:rustfmt_autosave = 0
let g:rustfmt_autosave_because_of_config = v:null
let g:rustfmt_autosave_if_config_present = 1
let g:rustfmt_command = 'rustfmt'
let g:rustfmt_emit_files = 1
let g:rustfmt_fail_silently = 0
let g:rustfmt_options = ''
let g:syntastic_extra_filetypes = ['rust']
let g:syntastic_rust_cargo_fname = v:null
rustfmt 0.99.4-nightly (1c40881 2018-08-27)

rustc 1.30.0-nightly (fc81e3624 2018-09-07)

cargo 1.29.0-nightly (0ec7281b9 2018-08-20)


NVIM v0.3.1
Build type: Release
LuaJIT 2.1.0-beta3
Compilation: /nix/store/wkfafgwgs1na5f808wybs8l6v8yjrvqz-gcc-wrapper-7.3.0/bin/gcc -Wconversion -O2 -DNDEBUG -DMIN_LOG_LEVEL=3 -Wall -Wextra -pedantic -Wno-unused-parameter -Wstrict-prototypes -std=gnu99 -Wimplicit-fallthrough -Wvla -fstack-protector-strong -fdiagnostics-color=auto -Wno-array-bounds -DINCLUDE_GENERATED_DECLARATIONS -D_GNU_SOURCE -DNVIM_MSGPACK_HAS_FLOAT32 -DNVIM_UNIBI_HAS_VAR_FROM -I/build/source/build/config -I/build/source/src -I/nix/store/3jzza70h4xlcl65py98y0ddq3sr3nv6z-libuv-1.21.0/include -I/nix/store/wqmabb91mn7c8l0cbagbi7n6b78r2k6g-libmsgpack-2.1.5/include -I/nix/store/qwlgay0pdgllmdwif144771z8y0anx3j-unibilium-2.0.0/include -I/nix/store/caygb8bjk106ja8fddlx2zw5fbzzz8g2-libtermkey-0.20/include -I/nix/store/r54qm8js4ndph7mqwm61fgpd54niwbxi-neovim-libvterm-2017-11-05/include -I/nix/store/k8fcymm135rp923s2w8w5z7wzr2kdcvi-jemalloc-5.0.1/include -I/nix/store/z10kkr081zb02kyjw8ybf2s9zll49cvx-glibc-2.27-dev/include -I/build/source/build/src/nvim/auto -I/build/source/build/include
Compiled by nixbld

Features: +acl +iconv +jemalloc +tui 
See ":help feature-compile"

   system vimrc file: "$VIM/sysinit.vim"
  fall-back for $VIM: "/nix/store/19sgqgn1vpc8c7828hhf0lmpaqx9yb8m-neovim-unwrapped-0.3.1/share/nvim"

Run :checkhealth for more info

[da-x]

Tried to reproduce with rustfmt 0.99.4-nightly, nvim 3.1, and crev-dev/cargo-crev@d9fbf06 to no avail. Just to clear out ambiguity regarding 'erased' - are the files actually being removed from the directory, or the buffers in which they are edited get emptied?

[dpc]

@da-x Thanks for checking. I will try to spend some time and dissect it.

The file is there, just empty.

I can do uu for two undoes, get the old content, but when I :w the file consistently keep being rewritten as empty.

[dpc]

After I've commented out call neomake#configure#automake('w') it stopped happening. When I used autocmd! BufWritePost,BufEnter *.rs Neomake cargo instead the problem is not happening.

I guess I'll log an issue against neomake.

[blueyed]

For reference: it also happens with the manual Neomake autocommand.
I've left some hints for debugging at neomake/neomake#2080 (comment).

[dpc]

Following instructions from neomake/neomake#2080

when doing :debug w:

function <SNR>20_SynSet                                                                                                         
line 26: endif                                                                                                                  
>                                                                                                                               
function <SNR>20_SynSet                                                                                                         
line 26: End of function                                                                                                        
>                                                                                                                               
function rustfmt#PreWrite[12]..<SNR>120_RunRustfmt                                                                              
line 43: if s:got_fmt_error                                                                                                     
>                                                                                                                               
function rustfmt#PreWrite[12]..<SNR>120_RunRustfmt                                                                              
line 47: endif                                                                                                                  
>                                                                                                                               
function rustfmt#PreWrite[12]..<SNR>120_RunRustfmt                                                                              
line 48: elseif g:rustfmt_fail_silently == 0 && a:fail_silently == 0                                                            
>                                                                                                                               
function rustfmt#PreWrite[12]..<SNR>120_RunRustfmt                                                                              
line 82: if a:tmpname ==# ''                                                                                                    
>                                                                                                                               
function rustfmt#PreWrite[12]..<SNR>120_RunRustfmt                                                                              
line 83: if l:has_lcd                                                                                                           
>                                                                                                                               
function rustfmt#PreWrite[12]..<SNR>120_RunRustfmt                                                                              
line 85: else                                                                                                                   
>                                                                                                                               
function rustfmt#PreWrite[12]..<SNR>120_RunRustfmt                                                                              
line 86: execute 'chdir! '.l:prev_cd                                                                                            
>                                                                                                                               
function rustfmt#PreWrite[12]..<SNR>120_RunRustfmt                                                                              
line 87: endif                                                                                                                  
>                                                                                                                               
function rustfmt#PreWrite[12]..<SNR>120_RunRustfmt                                                                              
line 88: endif                                                                                                                  
>                                                                                                                               
function rustfmt#PreWrite[12]..<SNR>120_RunRustfmt                                                                              
line 90: loadview                                                                                                               
>                                                                                                                               
function rustfmt#PreWrite[12]..<SNR>120_RunRustfmt                                                                              
line 90: End of function                                                                                                        
>                                                                                                                               
function rustfmt#PreWrite                                                                                                       
line 12: End of function                                                                                                        
>                                                                                                                               
BufWritePre Auto commands for "<buffer=3>"                                                                                      
cmd: call rustfmt#PreWrite()                                                                                                    
"crev-data/src/tests.rs" 0L, 0C written                                                                                         
BufWritePost Auto commands for "*"                                                                                              
cmd: set nottimeout           

The last output is the one after which the file became 0-sized.

I was doing strace at the same time, and it looks like the pid of rustfmt received empty input:

[pid 25699] execve("/home/dpc/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/bin/rustfmt", ["rustfmt", "--emit=stdout"], 0x
e687e0 /* 101 vars */ <unfinished ...>
(...)
[pid 25699] read(0, "", 8192)           = 0

[da-x]

@dpc is this issue still relevant? Thanks

[dpc]

No. It's fixed Neomake.