Support $GO111MODULE with Go tooling

Allows the user to override $GO111MODULE environment variable through
ale options. This gives control over the default behavior of Go module
resolution.

Golang documentation:
https://github.com/golang/go/wiki/Modules#how-to-use-modules

Add `ale#Go#EnvString()` function to make it easy to add similar Go
environment variables in the future.

Use the new `EnvString` function in all available Go tools callbacks
& update tests

Also add test of linter command callback for `gofmt`

ale_linters/go/bingo.vim

@@ -5,11 +5,13 @@ call ale#Set('go_bingo_executable', 'bingo')
 call ale#Set('go_bingo_options', '--mode stdio')
 
 function! ale_linters#go#bingo#GetCommand(buffer) abort
-    return '%e' . ale#Pad(ale#Var(a:buffer, 'go_bingo_options'))
+    return ale#go#EnvString(a:buffer) . '%e' . ale#Pad(ale#Var(a:buffer, 'go_bingo_options'))
 endfunction
 
 function! ale_linters#go#bingo#FindProjectRoot(buffer) abort
-    let l:project_root = ale#path#FindNearestFile(a:buffer, 'go.mod')
+    let l:go_modules_off = ale#Var(a:buffer, 'go_go111module') is# 'off'
+    let l:project_root = l:go_modules_off ?
+    \ '' : ale#path#FindNearestFile(a:buffer, 'go.mod')
     let l:mods = ':h'
 
     if empty(l:project_root)

ale_linters/go/gobuild.vim

@@ -11,6 +11,7 @@ function! ale_linters#go#gobuild#GetCommand(buffer) abort
 
     " Run go test in local directory with relative path
     return ale#path#BufferCdString(a:buffer)
+    \   . ale#go#EnvString(a:buffer)
     \   . ale#Var(a:buffer, 'go_go_executable') . ' test'
     \   . (!empty(l:options) ? ' ' . l:options : '')
     \   . ' -c -o /dev/null ./'

ale_linters/go/gofmt.vim

@@ -1,10 +1,16 @@
 " Author: neersighted <bjorn@neersighted.com>
 " Description: gofmt for Go files
 
+function! ale_linters#go#gofmt#GetCommand(buffer) abort
+    return ale#go#EnvString(a:buffer)
+    \   . '%e -e %t'
+endfunction
+
+
 call ale#linter#Define('go', {
 \   'name': 'gofmt',
 \   'output_stream': 'stderr',
 \   'executable': 'gofmt',
-\   'command': 'gofmt -e %t',
+\   'command': function('ale_linters#go#gofmt#GetCommand'),
 \   'callback': 'ale#handlers#unix#HandleAsError',
 \})

ale_linters/go/golangci_lint.vim

@@ -10,13 +10,16 @@ function! ale_linters#go#golangci_lint#GetCommand(buffer) abort
     let l:options = ale#Var(a:buffer, 'go_golangci_lint_options')
     let l:lint_package = ale#Var(a:buffer, 'go_golangci_lint_package')
 
+
     if l:lint_package
         return ale#path#BufferCdString(a:buffer)
+        \   . ale#go#EnvString(a:buffer)
         \   . '%e run '
         \   .  l:options
     endif
 
     return ale#path#BufferCdString(a:buffer)
+    \   . ale#go#EnvString(a:buffer)
     \   . '%e run '
     \   . ale#Escape(l:filename)
     \   . ' ' . l:options

ale_linters/go/golint.vim

@@ -7,7 +7,7 @@ call ale#Set('go_golint_options', '')
 function! ale_linters#go#golint#GetCommand(buffer) abort
     let l:options = ale#Var(a:buffer, 'go_golint_options')
 
-    return '%e'
+    return ale#go#EnvString(a:buffer) . '%e'
     \   . (!empty(l:options) ? ' ' . l:options : '')
     \   . ' %t'
 endfunction

ale_linters/go/gometalinter.vim

@@ -14,11 +14,13 @@ function! ale_linters#go#gometalinter#GetCommand(buffer) abort
     " be calculated to absolute paths in the Handler
     if l:lint_package
         return ale#path#BufferCdString(a:buffer)
+        \   . ale#go#EnvString(a:buffer)
         \   . '%e'
         \   . (!empty(l:options) ? ' ' . l:options : '') . ' .'
     endif
 
     return ale#path#BufferCdString(a:buffer)
+    \   . ale#go#EnvString(a:buffer)
     \   . '%e'
     \   . ' --include=' . ale#Escape(ale#util#EscapePCRE(l:filename))
     \   . (!empty(l:options) ? ' ' . l:options : '') . ' .'

ale_linters/go/gopls.vim

@@ -6,11 +6,15 @@ call ale#Set('go_gopls_executable', 'gopls')
 call ale#Set('go_gopls_options', '--mode stdio')
 
 function! ale_linters#go#gopls#GetCommand(buffer) abort
-    return '%e' . ale#Pad(ale#Var(a:buffer, 'go_gopls_options'))
+    return ale#go#EnvString(a:buffer)
+    \   . '%e'
+    \   . ale#Pad(ale#Var(a:buffer, 'go_gopls_options'))
 endfunction
 
 function! ale_linters#go#gopls#FindProjectRoot(buffer) abort
-    let l:project_root = ale#path#FindNearestFile(a:buffer, 'go.mod')
+    let l:go_modules_off = ale#Var(a:buffer, 'go_go111module') is# 'off'
+    let l:project_root = l:go_modules_off ?
+    \ '' : ale#path#FindNearestFile(a:buffer, 'go.mod')
     let l:mods = ':h'
 
     if empty(l:project_root)

ale_linters/go/gosimple.vim

@@ -2,7 +2,8 @@
 " Description: gosimple for Go files
 
 function! ale_linters#go#gosimple#GetCommand(buffer) abort
-    return ale#path#BufferCdString(a:buffer) . ' gosimple .'
+    return ale#path#BufferCdString(a:buffer) . ' '
+    \   . ale#go#EnvString(a:buffer) . 'gosimple .'
 endfunction
 
 call ale#linter#Define('go', {

ale_linters/go/gotype.vim

@@ -6,7 +6,8 @@ function! ale_linters#go#gotype#GetCommand(buffer) abort
         return ''
     endif
 
-    return ale#path#BufferCdString(a:buffer) . ' gotype -e .'
+    return ale#path#BufferCdString(a:buffer) . ' '
+    \   . ale#go#EnvString(a:buffer) . 'gotype -e .'
 endfunction
 
 call ale#linter#Define('go', {

ale_linters/go/govet.vim

@@ -11,6 +11,7 @@ function! ale_linters#go#govet#GetCommand(buffer) abort
     let l:options = ale#Var(a:buffer, 'go_govet_options')
 
     return ale#path#BufferCdString(a:buffer) . ' '
+    \   . ale#go#EnvString(a:buffer)
     \   . ale#Var(a:buffer, 'go_go_executable') . ' vet '
     \   . (!empty(l:options) ? ' ' . l:options : '')
     \   . ' .'

ale_linters/go/langserver.vim

@@ -15,8 +15,9 @@ function! ale_linters#go#langserver#GetCommand(buffer) abort
     endif
 
     let l:options = uniq(sort(l:options))
+    let l:env = ale#go#EnvString(a:buffer)
 
-    return join(extend(l:executable, l:options), ' ')
+    return l:env . join(extend(l:executable, l:options), ' ')
 endfunction
 
 call ale#linter#Define('go', {

ale_linters/go/staticcheck.vim

@@ -8,17 +8,18 @@ function! ale_linters#go#staticcheck#GetCommand(buffer) abort
     let l:filename = expand('#' . a:buffer . ':t')
     let l:options = ale#Var(a:buffer, 'go_staticcheck_options')
     let l:lint_package = ale#Var(a:buffer, 'go_staticcheck_lint_package')
+    let l:env = ale#go#EnvString(a:buffer)
 
     " BufferCdString is used so that we can be sure the paths output from
     " staticcheck can be calculated to absolute paths in the Handler
     if l:lint_package
         return ale#path#BufferCdString(a:buffer)
-        \   . 'staticcheck'
+        \   . l:env . 'staticcheck'
         \   . (!empty(l:options) ? ' ' . l:options : '') . ' .'
     endif
 
     return ale#path#BufferCdString(a:buffer)
-    \   . 'staticcheck'
+    \   . l:env . 'staticcheck'
     \   . (!empty(l:options) ? ' ' . l:options : '')
     \   . ' ' . ale#Escape(l:filename)
 endfunction

autoload/ale/fixers/gofmt.vim

@@ -7,9 +7,10 @@ call ale#Set('go_gofmt_options', '')
 function! ale#fixers#gofmt#Fix(buffer) abort
     let l:executable = ale#Var(a:buffer, 'go_gofmt_executable')
     let l:options = ale#Var(a:buffer, 'go_gofmt_options')
+    let l:env = ale#go#EnvString(a:buffer)
 
     return {
-    \   'command': ale#Escape(l:executable)
+    \   'command': l:env . ale#Escape(l:executable)
     \       . ' -l -w'
     \       . (empty(l:options) ? '' : ' ' . l:options)
     \       . ' %t',

autoload/ale/fixers/goimports.vim

@@ -7,13 +7,14 @@ call ale#Set('go_goimports_options', '')
 function! ale#fixers#goimports#Fix(buffer) abort
     let l:executable = ale#Var(a:buffer, 'go_goimports_executable')
     let l:options = ale#Var(a:buffer, 'go_goimports_options')
+    let l:env = ale#go#EnvString(a:buffer)
 
     if !executable(l:executable)
         return 0
     endif
 
     return {
-    \   'command': ale#Escape(l:executable)
+    \   'command': l:env . ale#Escape(l:executable)
     \       . ' -l -w -srcdir %s'
     \       . (empty(l:options) ? '' : ' ' . l:options)
     \       . ' %t',

autoload/ale/fixers/gomod.vim

@@ -2,9 +2,10 @@ call ale#Set('go_go_executable', 'go')
 
 function! ale#fixers#gomod#Fix(buffer) abort
     let l:executable = ale#Var(a:buffer, 'go_go_executable')
+    let l:env = ale#go#EnvString(a:buffer)
 
     return {
-    \   'command': ale#Escape(l:executable) . ' mod edit -fmt %t',
+    \   'command': l:env . ale#Escape(l:executable) . ' mod edit -fmt %t',
     \   'read_temporary_file': 1,
     \}
 endfunction

autoload/ale/go.vim

@@ -25,3 +25,20 @@ function! ale#go#FindProjectRoot(buffer) abort
 
     return ''
 endfunction
+
+
+call ale#Set('go_go111module', '')
+
+" Return a string setting Go-specific environment variables
+function! ale#go#EnvString(buffer) abort
+    let l:env = ''
+
+    " GO111MODULE - turn go modules behavior on/off
+    let l:go111module = ale#Var(a:buffer, 'go_go111module')
+
+    if !empty(l:go111module)
+        let l:env = ale#Env('GO111MODULE', l:go111module) . l:env
+    endif
+
+    return l:env
+endfunction

doc/ale-go.txt

@@ -29,6 +29,15 @@ g:ale_go_go_executable                                    *g:ale_go_go_options*
   The executable that will be run for the `gobuild` and `govet` linters, and
   the `gomod` fixer.
 
+g:ale_go_go111module                                     *g:ale_go_go111module*
+                                                         *b:ale_go_go111module*
+  Type: |String|
+  Default: `''`
+
+  Override the value of the `$GO111MODULE` environment variable for
+  golang tools.
+
+
 
 ===============================================================================
 bingo                                                            *ale-go-bingo*

test/command_callback/test_bingo_command_callback.vader

@@ -9,6 +9,7 @@ After:
   endif
 
   unlet! b:ale_completion_enabled
+  unlet! b:ale_go_go111module
 
   call ale#assert#TearDownLinterTest()
 
@@ -34,6 +35,14 @@ Execute(should set bingo options):
   AssertLinter 'bingo',
   \ ale#Escape('bingo') . ' --mode stdio --trace'
 
+Execute(should support Go environment variables):
+  call ale#test#SetFilename('go_paths/go1/prj1/file.go')
+  let b:ale_go_go111module = 'on'
+
+  AssertLinter 'bingo',
+  \ ale#Env('GO111MODULE', 'on') . ale#Escape('bingo') . ' --mode stdio'
+
+
 Execute(Should return directory for 'go.mod' if found in parent directory):
   call ale#test#SetFilename('../go_files/test.go')
 
@@ -44,3 +53,20 @@ Execute(Should return nearest directory with '.git' if found in parent directory
   call mkdir(g:dir . '/.git')
 
   AssertLSPProject g:dir
+
+Execute(Should ignore 'go.mod' and return '.git' dir if modules off):
+  call ale#test#SetFilename('../go_files/test.go')
+
+  let b:ale_go_go111module = 'off'
+  let b:parent_dir = ale#path#Simplify(g:dir . '/..')
+  let b:git_dir = b:parent_dir . '/.git'
+
+  if !isdirectory(b:git_dir)
+    call mkdir(b:git_dir)
+  endif
+
+  AssertLSPProject b:parent_dir
+
+  call delete(b:git_dir, 'd')
+  unlet! b:parent_dir
+  unlet! b:git_dir

test/command_callback/test_gobuild_command_callback.vader

@@ -14,6 +14,16 @@ Execute(The default commands should be correct):
   \ ale#path#CdString(expand('%:p:h'))
   \   . 'go test -c -o /dev/null ./'
 
+Execute(Go environment variables should be supported):
+  let b:ale_go_go111module = 'on'
+
+  AssertLinter 'go',
+  \ ale#path#CdString(expand('%:p:h'))
+  \   . ale#Env('GO111MODULE', 'on')
+  \   . 'go test -c -o /dev/null ./'
+
+  unlet! b:ale_go_go111module
+
 Execute(Extra options should be supported):
   let g:ale_go_gobuild_options = '--foo-bar'
 

test/command_callback/test_gofmt_command_callback.vader

@@ -0,0 +1,19 @@
+Before:
+  call ale#assert#SetUpLinterTest('go', 'gofmt')
+  call ale#test#SetFilename('../go_files/testfile2.go')
+
+After:
+  call ale#assert#TearDownLinterTest()
+
+Execute(The default gofmt command should be correct):
+  AssertLinter 'gofmt',
+  \ ale#Escape('gofmt') . ' -e %t'
+
+Execute(The gofmt command should support Go environment variables):
+  let b:ale_go_go111module = 'on'
+
+  AssertLinter 'gofmt',
+  \ ale#Env('GO111MODULE', 'on')
+  \ . ale#Escape('gofmt') . ' -e %t'
+
+  unlet! b:ale_go_go111module

test/command_callback/test_golangci_lint_command_callback.vader

@@ -30,6 +30,18 @@ Execute(The golangci-lint callback should use configured options):
   \   . ' run ' . ale#Escape(expand('%' . ':t'))
   \   . ' --foobar'
 
+Execute(The golangci-lint callback should support environment variables):
+  let b:ale_go_go111module = 'on'
+
+  AssertLinter 'golangci-lint',
+  \ ale#path#CdString(expand('%:p:h'))
+  \   . ale#Env('GO111MODULE', 'on')
+  \   . ale#Escape('golangci-lint')
+  \   . ' run ' . ale#Escape(expand('%' . ':t'))
+  \   . ' --enable-all'
+
+  unlet! b:ale_go_go111module
+
 Execute(The golangci-lint `lint_package` option should use the correct command):
   let b:ale_go_golangci_lint_package = 1
 

test/command_callback/test_golangserver_command_callback.vader

@@ -14,6 +14,7 @@ After:
   Restore
 
   unlet! b:ale_completion_enabled
+  unlet! b:ale_go_go111module
   unlet! g:sep
 
   call ale#assert#TearDownLinterTest()
@@ -52,6 +53,12 @@ Execute(should ignore go-langserver -gocodecompletion option):
 
   AssertLinter 'go-langserver', ale#Escape('go-langserver') . ' -trace'
 
+Execute(should support Go environment variables):
+  let b:ale_go_go111module = 'on'
+
+  AssertLinter 'go-langserver',
+  \ ale#Env('GO111MODULE', 'on') . ale#Escape('go-langserver')
+
 Execute(should set go-langserver for go app1):
   call ale#test#SetFilename('go_paths/go1/prj1/file.go')
 

test/command_callback/test_golint_command_callbacks.vader

@@ -16,3 +16,11 @@ Execute(The golint options should be configurable):
   let b:ale_go_golint_options = '--foo'
 
   AssertLinter 'golint', ale#Escape('golint') . ' --foo %t'
+
+Execute(The golint command should support Go environment variables):
+  let b:ale_go_go111module = 'on'
+
+  AssertLinter 'golint',
+  \ ale#Env('GO111MODULE', 'on') . ale#Escape('golint') . ' %t'
+
+  unlet! b:ale_go_go111module

test/command_callback/test_gometalinter_command_callback.vader

@@ -30,6 +30,16 @@ Execute(The gometalinter callback should use configured options):
   \   . ' --include=' . ale#Escape(ale#util#EscapePCRE(expand('%' . ':t')))
   \   . ' --foobar' . ' .'
 
+Execute(The gometalinter should use configured environment variables):
+  let b:ale_go_go111module = 'off'
+  AssertLinter 'gometalinter',
+  \ ale#path#CdString(expand('%:p:h'))
+  \   . ale#Env('GO111MODULE', 'off')
+  \   . ale#Escape('gometalinter')
+  \   . ' --include=' . ale#Escape(ale#util#EscapePCRE(expand('%' . ':t')))
+  \   . ' .'
+  unlet! b:ale_go_go111module
+
 Execute(The gometalinter `lint_package` option should use the correct command):
   let b:ale_go_gometalinter_lint_package = 1
 

test/command_callback/test_gopls_command_callback.vader

@@ -8,6 +8,7 @@ After:
     call delete(g:dir . '/.git', 'd')
   endif
 
+  unlet! b:ale_go_go111module
   unlet! b:ale_completion_enabled
 
   call ale#assert#TearDownLinterTest()
@@ -34,6 +35,12 @@ Execute(should set gopls options):
   AssertLinter 'gopls',
   \ ale#Escape('gopls') . ' --mode stdio --trace'
 
+Execute(should support go environment variables):
+  let b:ale_go_go111module = 'off'
+
+  AssertLinter 'gopls',
+  \ ale#Env('GO111MODULE', 'off') . ale#Escape('gopls') . ' --mode stdio'
+
 Execute(Should return directory for 'go.mod' if found in parent directory):
   call ale#test#SetFilename('../go_files/test.go')
 
@@ -44,3 +51,20 @@ Execute(Should return nearest directory with '.git' if found in parent directory
   call mkdir(g:dir . '/.git')
 
   AssertLSPProject g:dir
+
+Execute(Should ignore 'go.mod' and return '.git' dir if modules off):
+  call ale#test#SetFilename('../go_files/test.go')
+
+  let b:ale_go_go111module = 'off'
+  let b:parent_dir = ale#path#Simplify(g:dir . '/..')
+  let b:git_dir = b:parent_dir . '/.git'
+
+  if !isdirectory(b:git_dir)
+    call mkdir(b:git_dir)
+  endif
+
+  AssertLSPProject b:parent_dir
+
+  call delete(b:git_dir, 'd')
+  unlet! b:parent_dir
+  unlet! b:git_dir

test/command_callback/test_gosimple_command_callback.vader

@@ -8,3 +8,12 @@ After:
 Execute(The default gosimple command should be correct):
   AssertLinter 'gosimple',
   \ ale#path#CdString(expand('%:p:h')) . ' gosimple .'
+
+Execute(The gosimple command should support Go environment variables):
+  let b:ale_go_go111module = 'on'
+
+  AssertLinter 'gosimple',
+  \ ale#path#CdString(expand('%:p:h')) . ' '
+  \ . ale#Env('GO111MODULE', 'on') . 'gosimple .'
+
+  unlet! b:ale_go_go111module

test/command_callback/test_gotype_command_callback.vader

@@ -13,3 +13,13 @@ Execute(The gotype callback should ignore test files):
   call ale#test#SetFilename('bla_test.go')
 
   AssertLinter 'gotype', ''
+
+Execute(The gotype callback should support Go environment variables):
+  let b:ale_go_go111module = 'on'
+
+  AssertLinter 'gotype',
+  \ ale#path#CdString(expand('%:p:h')) . ' '
+  \ . ale#Env('GO111MODULE', 'on')
+  \ . 'gotype -e .'
+
+  unlet! b:ale_go_go111module

test/command_callback/test_govet_command_callback.vader

@@ -17,3 +17,11 @@ Execute(Extra options should be supported):
 Execute(The executable should be configurable):
   let g:ale_go_go_executable = 'foobar'
   AssertLinter 'foobar', ale#path#CdString(expand('%:p:h')) . ' foobar vet  .'
+
+Execute(Go environment variables should be supported):
+  let b:ale_go_go111module = 'on'
+  AssertLinter 'go',
+  \ ale#path#CdString(expand('%:p:h')) . ' '
+  \ . ale#Env('GO111MODULE', 'on')
+  \ . 'go vet  .'
+  unlet! b:ale_go_go111module

test/command_callback/test_staticcheck_command_callback.vader

@@ -24,3 +24,20 @@ Execute(The staticcheck `lint_package` option should use the correct command):
 
   AssertLinter 'staticcheck',
   \ ale#path#CdString(expand('%:p:h')) . 'staticcheck .',
+
+Execute(The staticcheck callback should use the `GO111MODULE` option if set):
+  let b:ale_go_go111module = 'off'
+
+  AssertLinter 'staticcheck',
+  \ ale#path#CdString(expand('%:p:h'))
+  \   . ale#Env('GO111MODULE', 'off')
+  \   . 'staticcheck '
+  \   . ale#Escape(expand('%' . ':t'))
+
+  " Test with lint_package option set
+  let b:ale_go_staticcheck_lint_package = 1
+  AssertLinter 'staticcheck',
+  \ ale#path#CdString(expand('%:p:h'))
+  \   . ale#Env('GO111MODULE', 'off')
+  \   . 'staticcheck .'
+  unlet! b:ale_go_go111module

test/fixers/test_gofmt_fixer_callback.vader

@@ -5,6 +5,7 @@ Before:
   " Use an invalid global executable, so we don't match it.
   let g:ale_go_gofmt_executable = 'xxxinvalid'
   let g:ale_go_gofmt_options = ''
+  let g:ale_go_go111module = ''
 
   call ale#test#SetDirectory('/testplugin/test/fixers')
 
@@ -38,3 +39,16 @@ Execute(The gofmt callback should include custom gofmt options):
   \     . ' %t',
   \ },
   \ ale#fixers#gofmt#Fix(bufnr(''))
+
+Execute(The gofmt callback should support Go environment variables):
+  let g:ale_go_go111module = 'off'
+  call ale#test#SetFilename('../go_files/testfile.go')
+
+  AssertEqual
+  \ {
+  \   'read_temporary_file': 1,
+  \   'command': ale#Env('GO111MODULE', 'off')
+  \     . ale#Escape('xxxinvalid') . ' -l -w'
+  \     . ' %t',
+  \ },
+  \ ale#fixers#gofmt#Fix(bufnr(''))

test/fixers/test_goimports_fixer_callback.vader

@@ -5,6 +5,7 @@ Before:
   " Use an invalid global executable, so we don't match it.
   let g:ale_go_goimports_executable = 'xxxinvalid'
   let g:ale_go_goimports_options = ''
+  let g:ale_go_go111module = ''
 
   call ale#test#SetDirectory('/testplugin/test/fixers')
   call ale#test#SetFilename('../go_files/testfile.go')
@@ -39,3 +40,16 @@ Execute(The goimports callback should include extra options):
   \   'command': ale#Escape(g:ale_go_goimports_executable) . ' -l -w -srcdir %s --xxx %t'
   \ },
   \ ale#fixers#goimports#Fix(bufnr(''))
+
+Execute(The goimports callback should support Go environment variables):
+  let g:ale_go_goimports_executable = has('win32') ? 'cmd' : 'echo'
+  let g:ale_go_go111module = 'on'
+
+  AssertEqual
+  \ {
+  \   'read_temporary_file': 1,
+  \   'command': ale#Env('GO111MODULE', 'on')
+  \     . ale#Escape(g:ale_go_goimports_executable)
+  \     . ' -l -w -srcdir %s %t'
+  \ },
+  \ ale#fixers#goimports#Fix(bufnr(''))

test/fixers/test_gomod_fixer_callback.vader

@@ -3,6 +3,7 @@ Before:
 
   " Use an invalid global executable, so we don't match it.
   let g:ale_go_go_executable = 'xxxinvalid'
+  let g:ale_go_go111module = ''
   call ale#test#SetDirectory('/testplugin/test/fixers')
 
 After:
@@ -12,7 +13,7 @@ After:
 
 Execute(The gomod callback should return the correct default values):
   call ale#test#SetFilename('../go_files/go.mod')
-  setl ft=gomod
+  setl filetype=gomod
 
   AssertEqual
   \ {
@@ -22,3 +23,16 @@ Execute(The gomod callback should return the correct default values):
   \     . ' %t',
   \ },
   \ ale#fixers#gomod#Fix(bufnr(''))
+
+Execute(The gomod callback should support Go environment variables):
+  call ale#test#SetFilename('../go_files/go.mod')
+  setl filetype=gomod
+  let g:ale_go_go111module = 'on'
+
+  AssertEqual
+  \ {
+  \   'read_temporary_file': 1,
+  \   'command': ale#Env('GO111MODULE', 'on')
+  \     . ale#Escape('xxxinvalid') . ' mod edit -fmt %t'
+  \ },
+  \ ale#fixers#gomod#Fix(bufnr(''))