Fix #1030. Autopep8 Executable did not handle older and newer versions

Older Autopep8 printed version to stderr, newer version to stdout.

See https://github.com/Glavin001/atom-beautify/issues/1030#issuecomment-309318598

src/beautifiers/autopep8.coffee

@@ -18,7 +18,7 @@ module.exports = class Autopep8 extends Beautifier
       version: {
         parse: (text) -> text.match(/autopep8 (\d+\.\d+\.\d+)/)[1]
         runOptions: {
-          returnStderr: true
+          returnStdoutOrStderr: true
         }
       }
       docker: {
@@ -41,7 +41,7 @@ module.exports = class Autopep8 extends Beautifier
     Python: true
   }
 
-  beautify: (text, language, options) ->
+  beautify: (text, language, options, context = {}) ->
     @exe("autopep8").run([
         tempFile = @tempFile("input", text)
         "-i"
@@ -51,17 +51,8 @@ module.exports = class Autopep8 extends Beautifier
       ])
       .then(=>
         if options.sort_imports
-          editor = atom.workspace.getActiveTextEditor()
-          filePath = editor.getPath()
-          projectPath = atom.project.relativizePath(filePath)[0]
-
-          @exe("isort")
-            .run(
-              ["-sp", projectPath, tempFile],
-            )
-            .then(=>
-              @readFile(tempFile)
-            )
-        else
-          @readFile(tempFile)
+          filePath = context.filePath
+          projectPath = atom?.project.relativizePath(filePath)[0]
+          @exe("isort").run(["-sp", projectPath, tempFile])
       )
+      .then(=> @readFile(tempFile))

src/beautifiers/executable.coffee

@@ -129,7 +129,7 @@ class Executable
   ###
   run: (args, options = {}) ->
     @debug("Run: ", @cmd, args, options)
-    { cwd, ignoreReturnCode, help, onStdin, returnStderr } = options
+    { cwd, ignoreReturnCode, help, onStdin, returnStderr, returnStdoutOrStderr } = options
     exeName = @cmd
     config = @getConfig()
     cwd ?= os.tmpDir()
@@ -179,7 +179,9 @@ class Executable
               else
                 throw new Error(stderr or stdout)
             else
-              if returnStderr
+              if returnStdoutOrStderr
+                return stdout or stderr
+              else if returnStderr
                 stderr
               else
                 stdout