Fix #735 - Support old versions of Flow by only adding --respect-pragma for supported versions

ale_linters/javascript/flow.vim

@@ -10,7 +10,12 @@ function! ale_linters#javascript#flow#GetExecutable(buffer) abort
     \])
 endfunction
 
-function! ale_linters#javascript#flow#GetCommand(buffer) abort
+function! ale_linters#javascript#flow#VersionCheck(buffer) abort
+    return ale#Escape(ale_linters#javascript#flow#GetExecutable(a:buffer))
+    \   . ' --version'
+endfunction
+
+function! ale_linters#javascript#flow#GetCommand(buffer, version_lines) abort
     let l:flow_config = ale#path#FindNearestFile(a:buffer, '.flowconfig')
 
     if empty(l:flow_config)
@@ -18,8 +23,21 @@ function! ale_linters#javascript#flow#GetCommand(buffer) abort
         return ''
     endif
 
+    let l:use_respect_pragma = 1
+
+    " If we can parse the version number, then only use --respect-pragma
+    " if the version is >= 0.36.0, which added the argument.
+    for l:match in ale#util#GetMatches(a:version_lines, '\v\d+\.\d+\.\d+$')
+        let l:use_respect_pragma = ale#semver#GreaterOrEqual(
+        \   ale#semver#Parse(l:match[0]),
+        \   [0, 36, 0]
+        \)
+    endfor
+
     return ale#Escape(ale_linters#javascript#flow#GetExecutable(a:buffer))
-    \   . ' check-contents --respect-pragma --json --from ale %s'
+    \   . ' check-contents'
+    \   . (l:use_respect_pragma ? ' --respect-pragma': '')
+    \   . ' --json --from ale %s'
 endfunction
 
 function! ale_linters#javascript#flow#Handle(buffer, lines) abort
@@ -74,6 +92,10 @@ endfunction
 call ale#linter#Define('javascript', {
 \   'name': 'flow',
 \   'executable_callback': 'ale_linters#javascript#flow#GetExecutable',
-\   'command_callback': 'ale_linters#javascript#flow#GetCommand',
+\   'command_chain': [
+\       {'callback': 'ale_linters#javascript#flow#VersionCheck'},
+\       {'callback': 'ale_linters#javascript#flow#GetCommand'},
+\   ],
 \   'callback': 'ale_linters#javascript#flow#Handle',
+\   'add_newline': 1,
 \})

autoload/ale/engine.vim

@@ -387,6 +387,16 @@ function! s:RunJob(options) abort
         let l:read_buffer = 0
     endif
 
+    " Add a newline to commands which need it.
+    " This is only used for Flow for now, and is not documented.
+    if l:linter.add_newline
+        if has('win32')
+            let l:command = l:command . '; echo.'
+        else
+            let l:command = l:command . '; echo'
+        endif
+    endif
+
     let l:command = ale#job#PrepareCommand(l:command)
     let l:job_options = {
     \   'mode': 'nl',

autoload/ale/linter.vim

@@ -50,6 +50,7 @@ function! ale#linter#PreProcess(linter) abort
     endif
 
     let l:obj = {
+    \   'add_newline': get(a:linter, 'add_newline', 0),
     \   'name': get(a:linter, 'name'),
     \   'lsp': get(a:linter, 'lsp', ''),
     \}

test/test_flow_command.vader

@@ -8,10 +8,21 @@ Execute(flow should return a command to run if a .flowconfig file exists):
   silent! cd /testplugin/test
   :e! flow/a/sub/dummy
 
-  AssertEqual '''flow'' check-contents --respect-pragma --json --from ale %s', ale_linters#javascript#flow#GetCommand(bufnr('%'))
+  AssertEqual '''flow'' check-contents --respect-pragma --json --from ale %s', ale_linters#javascript#flow#GetCommand(bufnr('%'), [])
+
+Execute(flow should should not use --respect-pragma for old versions):
+  silent! cd /testplugin/test
+  :e! flow/a/sub/dummy
+
+  AssertEqual
+  \ '''flow'' check-contents --json --from ale %s',
+  \ ale_linters#javascript#flow#GetCommand(bufnr('%'), [
+  \   'Warning: `flow --version` is deprecated in favor of `flow version`',
+  \   'Flow, a static type checker for JavaScript, version 0.27.0',
+  \ ])
 
 Execute(flow should not return a command to run if no .flowconfig file exists):
   silent! cd /testplugin/test
   :e! flow/b/sub/dummy
 
-  AssertEqual '', ale_linters#javascript#flow#GetCommand(bufnr('%'))
+  AssertEqual '', ale_linters#javascript#flow#GetCommand(bufnr('%'), [])

test/test_linter_retrieval.vader

@@ -1,8 +1,8 @@
 Before:
   Save g:ale_linters, g:ale_linter_aliases
 
-  let g:testlinter1 = {'name': 'testlinter1', 'executable': 'testlinter1', 'command': 'testlinter1', 'callback': 'testCB1', 'output_stream': 'stdout', 'read_buffer': 1, 'lint_file': 0, 'aliases': [], 'lsp': ''}
+  let g:testlinter1 = {'name': 'testlinter1', 'executable': 'testlinter1', 'command': 'testlinter1', 'callback': 'testCB1', 'output_stream': 'stdout', 'read_buffer': 1, 'lint_file': 0, 'aliases': [], 'lsp': '', 'add_newline': 0}
-  let g:testlinter2 = {'name': 'testlinter2', 'executable': 'testlinter2', 'command': 'testlinter2', 'callback': 'testCB2', 'output_stream': 'stdout', 'read_buffer': 0, 'lint_file': 1, 'aliases': [], 'lsp': ''}
+  let g:testlinter2 = {'name': 'testlinter2', 'executable': 'testlinter2', 'command': 'testlinter2', 'callback': 'testCB2', 'output_stream': 'stdout', 'read_buffer': 0, 'lint_file': 1, 'aliases': [], 'lsp': '', 'add_newline': 0}
   call ale#linter#Reset()
 
 After:
@@ -105,7 +105,7 @@ Execute (The local alias option shouldn't completely replace the global one):
   AssertEqual [g:testlinter1, g:testlinter2], ale#linter#Get('testft1')
 
 Execute (Linters should be loaded from disk appropriately):
-  AssertEqual [{'name': 'testlinter', 'output_stream': 'stdout', 'executable': 'testlinter', 'command': 'testlinter', 'callback': 'testCB', 'read_buffer': 1, 'lint_file': 0, 'aliases': [], 'lsp': ''}], ale#linter#Get('testft')
+  AssertEqual [{'name': 'testlinter', 'output_stream': 'stdout', 'executable': 'testlinter', 'command': 'testlinter', 'callback': 'testCB', 'read_buffer': 1, 'lint_file': 0, 'aliases': [], 'lsp': '', 'add_newline': 0}], ale#linter#Get('testft')
 
 
 Execute (Linters for later filetypes should replace the former ones):
@@ -123,5 +123,5 @@ Execute (Linters for later filetypes should replace the former ones):
   \})
 
   AssertEqual [
-  \ {'output_stream': 'stdout', 'lint_file': 0, 'read_buffer': 1, 'name': 'eslint', 'executable': 'x', 'lsp': '', 'aliases': [], 'command': 'x', 'callback': 'x'}
+  \ {'output_stream': 'stdout', 'lint_file': 0, 'read_buffer': 1, 'name': 'eslint', 'executable': 'x', 'lsp': '', 'aliases': [], 'command': 'x', 'callback': 'x', 'add_newline': 0}
   \], ale#linter#Get('javascript.typescript')