provider/pythonx: only call system("python") once

`s:check_interpreter` will query/return the version also, so that
`s:check_version` can just use that, without calling "python" again.

1 files changed, 12 insertions, 13 deletions

diff --git a/runtime/autoload/provider/pythonx.vim b/runtime/autoload/provider/pythonx.vim
index 6137d16fcb..1fe6c066ab 100644
--- a/runtime/autoload/provider/pythonx.vim
+++ b/runtime/autoload/provider/pythonx.vim
@@ -13,7 +13,7 @@ function! provider#pythonx#Detect(ver) abort
   let skip = exists(skip_var) ? {skip_var} : 0
   if exists(host_var)
     " Disable auto detection
-    let [check, err] = s:check_interpreter({host_var}, a:ver, skip)
+    let [check, err, _] = s:check_interpreter({host_var}, a:ver, skip)
     return check ? [{host_var}, err] : ['', err]
   endif
 
@@ -22,9 +22,9 @@ function! provider#pythonx#Detect(ver) abort
         \ : ['3.5', '3.4', '3.3', '3.2', '3', '']
 
   for prog in map(detect_versions, "'python' . v:val")
-    let [check, err] = s:check_interpreter(prog, a:ver, skip)
+    let [check, err, ver] = s:check_interpreter(prog, a:ver, skip)
     if check
-      let [check, err] = s:check_version(prog, a:ver, skip)
+      let [check, err] = s:check_version(prog, ver, skip)
       return [prog, err]
     endif
   endfor
@@ -39,31 +39,30 @@ function! s:check_version(prog, ver, skip) abort
     return [1, '']
   endif
 
-  let get_version =
-        \ ' -c "import sys; sys.stdout.write(str(sys.version_info[0]) + '.
-        \ '\".\" + str(sys.version_info[1]))"'
-  let min_version = (a:ver == 2) ? '2.6' : '3.3'
-  if system(a:prog . get_version) >= min_version
+  let min_version = (a:ver[0] == 2) ? '2.6' : '3.3'
+  if a:ver >= min_version
     return [1, '']
   endif
-  return [0, 'Python ' . get_version . ' interpreter is not supported.']
+  return [0, 'Python ' . a:ver . ' interpreter is not supported.']
 endfunction
 
 function! s:check_interpreter(prog, ver, skip) abort
   if !executable(a:prog)
-    return [0, 'Python'.a:ver.' interpreter is not executable.']
+    return [0, 'Python'.a:ver.' interpreter is not executable.', '']
   endif
 
   if a:skip
-    return [1, '']
+    return [1, '', '']
   endif
 
   " Load neovim module check
-  call system(a:prog . ' -c ' .
+  let ver = system(a:prog . ' -c ' .
+        \ '''import sys; sys.stdout.write(str(sys.version_info[0]) + '.
+        \ '"." + str(sys.version_info[1])); '''.
         \ (a:ver == 2 ?
         \   '''import pkgutil; exit(pkgutil.get_loader("neovim") is None)''':
         \   '''import importlib; exit(importlib.find_loader("neovim") is None)''')
         \ )
-  return [!v:shell_error, 'Python'.a:ver.' interpreter have not neovim module.']
+  return [!v:shell_error, 'Python'.a:ver.' interpreter have not neovim module.', ver]
 endfunction