Lint whole package for gosimple and gotype

Fixes #936

ale_linters/go/gosimple.vim

@@ -1,10 +1,14 @@
 " Author: Ben Reedy <https://github.com/breed808>
 " Description: gosimple for Go files
 
+function! ale_linters#go#gosimple#GetCommand(buffer) abort
+    return ale#path#BufferCdString(a:buffer) . ' gosimple .'
+endfunction
+
 call ale#linter#Define('go', {
 \   'name': 'gosimple',
 \   'executable': 'gosimple',
-\   'command': 'gosimple %s',
+\   'command_callback': 'ale_linters#go#gosimple#GetCommand',
 \   'callback': 'ale#handlers#unix#HandleAsWarning',
 \   'output_stream': 'both',
 \   'lint_file': 1,

ale_linters/go/gotype.vim

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

test/command_callback/test_gosimple_command_callback.vader

@@ -0,0 +1,12 @@
+Before:
+  runtime ale_linters/go/gosimple.vim
+  call ale#test#SetFilename('../go_files/testfile2.go')
+
+After:
+  call ale#linter#Reset()
+
+Execute(The default gosimple command should be correct):
+  AssertEqual 'cd ' . ale#Escape(expand('%:p:h')) . ' && '
+  \ . ' gosimple .',
+  \ ale_linters#go#gosimple#GetCommand(bufnr(''))
+

test/command_callback/test_gotype_command_callback.vader

@@ -6,7 +6,9 @@ After:
   call ale#linter#Reset()
 
 Execute(The default gotype command should be correct):
-  AssertEqual 'gotype %s', ale_linters#go#gotype#GetCommand(bufnr(''))
+  AssertEqual 'cd ' . ale#Escape(expand('%:p:h')) . ' && '
+  \ . ' gotype .',
+  \ ale_linters#go#gotype#GetCommand(bufnr(''))
 
 Execute(The gotype callback should ignore test files):
   call ale#test#SetFilename('bla_test.go')