Python: Prioritize closest viable bracket

That way, the order of nesting {, [, or ( doesn't matter. Strings are
still a bit of a pain.

Author: AndrewRadev

autoload/sj/python.vim

@@ -19,6 +19,23 @@ function! sj#python#JoinStatement()
   endif
 endfunction
 
+function! sj#python#SplitBracketedItem() abort
+  let closest_bracket_line = search('[{([]', 'bcW', line('.'), 0, s:skip)
+  if closest_bracket_line <= 0
+    return
+  endif
+
+  let bracket = getline('.')[col('.') - 1]
+
+  if bracket == '('
+    return sj#python#SplitTuple()
+  elseif bracket == '['
+    return sj#python#SplitArray()
+  elseif bracket == '{'
+    return sj#python#SplitDict()
+  endif
+endfunction
+
 function! sj#python#SplitDict()
   let [from, to] = sj#LocateBracesAroundCursor('{', '}', ['pythonString'])
 

ftplugin/python/splitjoin.vim

@@ -2,12 +2,10 @@ if !exists('b:splitjoin_split_callbacks')
   let b:splitjoin_split_callbacks = [
         \ 'sj#python#SplitString',
         \ 'sj#python#SplitListComprehension',
-        \ 'sj#python#SplitDict',
-        \ 'sj#python#SplitTuple',
         \ 'sj#python#SplitArgs',
+        \ 'sj#python#SplitBracketedItem',
         \ 'sj#python#SplitAssignment',
         \ 'sj#python#SplitTernaryAssignment',
-        \ 'sj#python#SplitArray',
         \ 'sj#python#SplitStatement',
         \ 'sj#python#SplitImport',
         \ ]

spec/plugin/python_spec.rb

@@ -360,6 +360,48 @@ def example():
     EOF
   end
 
+  specify "split prioritization based on cursor position" do
+    set_file_contents "spam = {'spam': [1, 2, 3], 'spam, spam': mix('eggs', 'ham')}"
+
+    vim.search('{')
+    split
+
+    assert_file_contents <<~EOF
+      spam = {
+              'spam': [1, 2, 3],
+              'spam, spam': mix('eggs', 'ham')
+              }
+    EOF
+    join
+
+    vim.search('[')
+    split
+
+    assert_file_contents <<~EOF
+      spam = {'spam': [1,
+                       2,
+                       3], 'spam, spam': mix('eggs', 'ham')}
+    EOF
+    join
+
+    vim.search('mix(')
+    split
+
+    assert_file_contents <<~EOF
+      spam = {'spam': [1, 2, 3], 'spam, spam': mix('eggs',
+                                                   'ham')}
+    EOF
+    join
+
+    vim.search('(')
+    split
+
+    assert_file_contents <<~EOF
+      spam = {'spam': [1, 2, 3], 'spam, spam': mix('eggs',
+                                                   'ham')}
+    EOF
+  end
+
   describe "strings" do
     it "joins ''' strings into single-quoted strings" do
       set_file_contents <<~EOF