Fix #1115 - Add support for wrapping all commands with an option

autoload/ale/engine.vim

@@ -512,7 +512,7 @@ function! s:RunJob(options) abort
         endif
     endif
 
-    let l:command = ale#job#PrepareCommand(l:command)
+    let l:command = ale#job#PrepareCommand(l:buffer, l:command)
     let l:job_options = {
     \   'mode': 'nl',
     \   'exit_cb': function('s:HandleExit'),

autoload/ale/fix.vim

@@ -222,7 +222,7 @@ function! s:RunJob(options) abort
     \)
     call s:CreateTemporaryFileForJob(l:buffer, l:temporary_file, l:input)
 
-    let l:command = ale#job#PrepareCommand(l:command)
+    let l:command = ale#job#PrepareCommand(l:buffer, l:command)
     let l:job_options = {
     \   'mode': 'nl',
     \   'exit_cb': function('s:HandleExit'),

autoload/ale/job.vim

@@ -165,23 +165,54 @@ function! ale#job#ValidateArguments(command, options) abort
     endif
 endfunction
 
-function! ale#job#PrepareCommand(command) abort
+function! s:PrepareWrappedCommand(original_wrapper, command) abort
+    let l:match = matchlist(a:command, '\v^(.*(\&\&|;)) *(.*)$')
+    let l:prefix = ''
+    let l:command = a:command
+
+    if !empty(l:match)
+        let l:prefix = l:match[1] . ' '
+        let l:command = l:match[3]
+    endif
+
+    let l:format = a:original_wrapper
+
+    if l:format =~# '%@'
+        let l:wrapped = substitute(l:format, '%@', ale#Escape(l:command), '')
+    else
+        if l:format !~# '%\*'
+            let l:format .= ' %*'
+        endif
+
+        let l:wrapped = substitute(l:format, '%\*', l:command, '')
+    endif
+
+    return l:prefix . l:wrapped
+endfunction
+
+function! ale#job#PrepareCommand(buffer, command) abort
+    let l:wrapper = ale#Var(a:buffer, 'command_wrapper')
+
+    let l:command = !empty(l:wrapper)
+    \ ? s:PrepareWrappedCommand(l:wrapper, a:command)
+    \ : a:command
+
     " The command will be executed in a subshell. This fixes a number of
     " issues, including reading the PATH variables correctly, %PATHEXT%
     " expansion on Windows, etc.
     "
     " NeoVim handles this issue automatically if the command is a String,
-    " but we'll do this explicitly, so we use thes same exact command for both
+    " but we'll do this explicitly, so we use the same exact command for both
     " versions.
-    if ale#Has('win32')
+    if has('win32')
-        return 'cmd /c ' . a:command
+        return 'cmd /c ' . l:command
     endif
 
     if &shell =~? 'fish$'
-        return ['/bin/sh', '-c', a:command]
+        return ['/bin/sh', '-c', l:command]
     endif
 
-    return split(&shell) + split(&shellcmdflag) + [a:command]
+    return split(&shell) + split(&shellcmdflag) + [l:command]
 endfunction
 
 " Start a job with options which are agnostic to Vim and NeoVim.

autoload/ale/linter.vim

@@ -1,3 +1,4 @@
+call ale#Set('wrap_command_as_one_argument', 0)
 " Author: w0rp <devw0rp@gmail.com>
 " Description: Linter registration and lazy-loading
 "   Retrieves linters as requested by the engine, loading them if needed.
@@ -432,6 +433,7 @@ function! ale#linter#StartLSP(buffer, linter, callback) abort
         endif
 
         let l:command = ale#job#PrepareCommand(
+        \   a:buffer,
         \   ale#linter#GetCommand(a:buffer, a:linter),
         \)
         let l:conn_id = ale#lsp#StartProgram(

doc/ale.txt

@@ -646,6 +646,39 @@ g:ale_change_sign_column_color                 *g:ale_change_sign_column_color*
   windows.
 
 
+g:ale_command_wrapper                                   *g:ale_command_wrapper*
+                                                        *b:ale_command_wrapper*
+  Type: |String|
+  Default: `''`
+
+  An option for wrapping all commands that ALE runs, for linters, fixers,
+  and LSP commands. This option can be set globally, or for specific buffers.
+
+  This option can be used to apply nice to all commands. For example: >
+
+    " Prefix all commands with nice.
+    let g:ale_command_wrapper = 'nice -n5'
+<
+  Use the |ALEInfo| command to view the commands that are run. All of the
+  arguments for commands will be put on the end of the wrapped command by
+  default. A `%*` marker can be used to spread the arguments in the wrapped
+  command. >
+
+    " Has the same effect as the above.
+    let g:ale_command_wrapper = 'nice -n5 %*'
+<
+
+  For passing all of the arguments for a command as one argument to a wrapper,
+  `%@` can be used instead. >
+
+    " Will result in say: /bin/bash -c 'other-wrapper -c "some command" -x'
+    let g:ale_command_wrapper = 'other-wrapper -c %@ -x'
+<
+  For commands including `&&` or `;`, only the last command in the list will
+  be passed to the wrapper. `&&` is most commonly used in ALE to change the
+  working directory before running a command.
+
+
 g:ale_completion_delay                                 *g:ale_completion_delay*
 
   Type: |Number|

plugin/ale.vim

@@ -209,6 +209,9 @@ call ale#Set('completion_enabled', 0)
 call ale#Set('completion_delay', 100)
 call ale#Set('completion_max_suggestions', 50)
 
+" A setting for wrapping commands.
+call ale#Set('command_wrapper', '')
+
 if g:ale_set_balloons
     call ale#balloon#Enable()
 endif

test/fix/test_ale_fix.vader

@@ -581,8 +581,8 @@ Execute(Test fixing with chained callbacks):
   " The buffer shouldn't be piped in for earlier commands in the chain.
   AssertEqual
   \ [
-  \   string(ale#job#PrepareCommand('echo echoline')),
+  \   string(ale#job#PrepareCommand(bufnr(''), 'echo echoline')),
-  \   string(ale#job#PrepareCommand('echo echoline')),
+  \   string(ale#job#PrepareCommand(bufnr(''), 'echo echoline')),
   \ ],
   \ map(ale#history#Get(bufnr(''))[-2:-1], 'string(v:val.command)')
 
@@ -635,7 +635,7 @@ Execute(A temporary file shouldn't be piped into the command when disabled):
   ALEFix
 
   AssertEqual
-  \ string(ale#job#PrepareCommand('echo new line')),
+  \ string(ale#job#PrepareCommand(bufnr(''), 'echo new line')),
   \ string(ale#history#Get(bufnr(''))[-1].command)
 
   " Remove trailing whitespace for Windows.

test/test_prepare_command.vader

@@ -4,35 +4,36 @@ Before:
 
 After:
   Restore
-  let g:ale_has_override = {}
 
 Execute(sh should be used when the shell is fish):
+  if !has('win32')
     " Set something else, so we will replace that too.
     let &shellcmdflag = '-f'
-  let g:ale_has_override = {'win32': 0}
-
     let &shell = 'fish'
 
-  AssertEqual ['/bin/sh', '-c', 'foobar'], ale#job#PrepareCommand('foobar')
+    AssertEqual ['/bin/sh', '-c', 'foobar'], ale#job#PrepareCommand(bufnr(''), 'foobar')
 
     let &shell = '/usr/bin/fish'
 
-  AssertEqual ['/bin/sh', '-c', 'foobar'], ale#job#PrepareCommand('foobar')
+    AssertEqual ['/bin/sh', '-c', 'foobar'], ale#job#PrepareCommand(bufnr(''), 'foobar')
 
     let &shell = '/usr/local/bin/fish'
 
-  AssertEqual ['/bin/sh', '-c', 'foobar'], ale#job#PrepareCommand('foobar')
+    AssertEqual ['/bin/sh', '-c', 'foobar'], ale#job#PrepareCommand(bufnr(''), 'foobar')
+  endif
 
 Execute(Other shells should be used when set):
+  if !has('win32')
     let &shell = '/bin/bash'
     let &shellcmdflag = '-c'
-  let g:ale_has_override = {'win32': 0}
 
-  AssertEqual ['/bin/bash', '-c', 'foobar'], ale#job#PrepareCommand('foobar')
+    AssertEqual ['/bin/bash', '-c', 'foobar'], ale#job#PrepareCommand(bufnr(''), 'foobar')
+  endif
 
 Execute(cmd /c as a string should be used on Windows):
+  if has('win32')
     let &shell = 'who cares'
     let &shellcmdflag = 'whatever'
-  let g:ale_has_override = {'win32': 1}
 
-  AssertEqual 'cmd /c foobar', ale#job#PrepareCommand('foobar')
+    AssertEqual 'cmd /c foobar', ale#job#PrepareCommand(bufnr(''), 'foobar')
+  endif

test/test_wrap_comand.vader

@@ -0,0 +1,48 @@
+Before:
+  Save g:ale_command_wrapper
+
+  let g:ale_command_wrapper = ''
+
+  function! TestCommand(expected_part, input) abort
+    let l:expected = has('win32')
+    \ ? 'cmd /c ' . a:expected_part
+    \ : split(&shell) + split(&shellcmdflag) + [a:expected_part]
+
+    AssertEqual l:expected, ale#job#PrepareCommand(bufnr(''), a:input)
+  endfunction
+
+After:
+  Restore
+
+  unlet! b:ale_command_wrapper
+
+  delfunction TestCommand
+
+Execute(The command wrapper should work with a nice command):
+  let b:ale_command_wrapper = 'nice -n 5'
+
+  call TestCommand('nice -n 5 foo bar', 'foo bar')
+
+Execute(The command wrapper should work with a nice command with an explicit marker):
+  let b:ale_command_wrapper = 'nice -n 5 %*'
+
+  call TestCommand('nice -n 5 foo bar', 'foo bar')
+
+Execute(Wrappers with spread arguments in the middle should be suppported):
+  let b:ale_command_wrapper = 'wrap %* --'
+
+  call TestCommand('wrap foo bar --', 'foo bar')
+
+Execute(Wrappers with the command as one argument should be supported):
+  let b:ale_command_wrapper = 'wrap -c %@ -x'
+
+  call TestCommand('wrap -c ' . ale#Escape('foo bar') . ' -x', 'foo bar')
+
+Execute(&& and ; should be moved to the front):
+  let b:ale_command_wrapper = 'wrap -c %@ -x'
+
+  call TestCommand('foo && bar; wrap -c ' . ale#Escape('baz') . ' -x', 'foo && bar;baz')
+
+  let b:ale_command_wrapper = 'nice -n 5'
+
+  call TestCommand('foo && bar; nice -n 5 baz -z', 'foo && bar;baz -z')