#591 Store buffer variables when fixing filess, and read them back in ale#Var

autoload/ale.vim

@@ -128,9 +128,18 @@ endfunction
 "
 " Every variable name will be prefixed with 'ale_'.
 function! ale#Var(buffer, variable_name) abort
+    let l:nr = str2nr(a:buffer)
     let l:full_name = 'ale_' . a:variable_name
 
-    return getbufvar(str2nr(a:buffer), l:full_name, g:[l:full_name])
+    if bufexists(l:nr)
+        let l:vars = getbufvar(l:nr, '')
+    elseif has_key(g:, 'ale_fix_buffer_data')
+        let l:vars = get(g:ale_fix_buffer_data, l:nr, {'vars': {}}).vars
+    else
+        let l:vars = {}
+    endif
+
+    return get(l:vars, l:full_name, g:[l:full_name])
 endfunction
 
 " Initialize a variable with a default value, if it isn't already set.

autoload/ale/fix.vim

@@ -305,6 +305,7 @@ function! ale#fix#InitBufferData(buffer, fixing_flag) abort
     " The 'done' flag tells the function for applying changes when fixing
     " is complete.
     let g:ale_fix_buffer_data[a:buffer] = {
+    \   'vars': getbufvar(a:buffer, ''),
     \   'lines_before': getbufline(a:buffer, 1, '$'),
     \   'filename': expand('#' . a:buffer . ':p'),
     \   'done': 0,

test/test_ale_fix.vader

@@ -11,6 +11,7 @@ Before:
   let g:ale_enabled = 0
   let g:ale_echo_cursor = 0
   let g:ale_run_synchronously = 1
+  let g:ale_fix_buffer_data = {}
   let g:ale_fixers = {
   \ 'testft': [],
   \}
@@ -75,6 +76,8 @@ After:
     call delete('fix_test_file')
   endif
 
+  let g:ale_fix_buffer_data = {}
+
 Given testft (A file with three lines):
   a
   b
@@ -291,3 +294,24 @@ Expect(The buffer should be the same):
   a
   b
   c
+
+Given testft (A file with three lines):
+  a
+  b
+  c
+
+Execute(ale#fix#InitBufferData() should set up the correct data):
+  noautocmd silent file fix_test_file
+
+  call ale#fix#InitBufferData(bufnr(''), 'save_file')
+
+  AssertEqual {
+  \ bufnr(''): {
+  \   'temporary_directory_list': [],
+  \   'vars': b:,
+  \   'filename': simplify(getcwd() . '/fix_test_file'),
+  \   'done': 0,
+  \   'lines_before': ['a', 'b', 'c'],
+  \   'should_save': 1,
+  \ },
+  \}, g:ale_fix_buffer_data

test/test_ale_var.vader

@@ -3,6 +3,9 @@ Before:
 
 After:
   unlet! g:ale_some_variable
+  unlet! b:undefined_variable_name
+
+  let g:ale_fix_buffer_data = {}
 
 Execute(ale#Var should return global variables):
   AssertEqual 'abc', ale#Var(bufnr(''), 'some_variable')
@@ -18,4 +21,21 @@ Execute(ale#Var should return buffer overrides for buffer numbers as strings):
   AssertEqual 'def', ale#Var(string(bufnr('')), 'some_variable')
 
 Execute(ale#Var should throw exceptions for undefined variables):
+  let b:undefined_variable_name = 'def'
+
   AssertThrows call ale#Var(bufnr(''), 'undefined_variable_name')
+
+Execute(ale#Var return variables from deleted buffers, saved for fixing things):
+  let g:ale_fix_buffer_data[1347347] = {'vars': {'ale_some_variable': 'def'}}
+
+  AssertEqual 'def', ale#Var(1347347, 'some_variable')
+
+Execute(ale#Var should return the global variable for unknown variables):
+  let g:ale_fix_buffer_data = {}
+
+  AssertEqual 'abc', ale#Var(1347347, 'some_variable')
+
+Execute(ale#Var should return the global variables when the ALE fix variable is undefined):
+  unlet! g:ale_fix_buffer_data
+
+  AssertEqual 'abc', ale#Var(1347347, 'some_variable')