Allow warnings about trailing whitespace to be disabled for pycodestyle, and cover the flake8 code with tests

ale_linters/python/pycodestyle.vim

@@ -23,6 +23,12 @@ function! ale_linters#python#pycodestyle#Handle(buffer, lines) abort
     " lines are formatted as follows:
     " file.py:21:26: W291 trailing whitespace
     for l:match in ale#util#GetMatches(a:lines, l:pattern)
+        if(l:match[4] is# 'W291' || l:match[4] is# 'W293')
+        \&& !ale#Var(a:buffer, 'warn_about_trailing_whitespace')
+            " Skip warnings for trailing whitespace if the option is off.
+            continue
+        endif
+
         if l:match[4] is# 'W391'
         \&& !ale#Var(a:buffer, 'warn_about_trailing_blank_lines')
             " Skip warnings for trailing blank lines if the option is off

test/handler/test_flake8_handler.vader

@@ -1,7 +1,9 @@
 Before:
   Save g:ale_warn_about_trailing_blank_lines
+  Save g:ale_warn_about_trailing_whitespace
 
   let g:ale_warn_about_trailing_blank_lines = 1
+  let g:ale_warn_about_trailing_whitespace = 1
 
   runtime ale_linters/python/flake8.vim
 
@@ -9,6 +11,7 @@ After:
   Restore
 
   unlet! b:ale_warn_about_trailing_blank_lines
+  unlet! b:ale_warn_about_trailing_whitespace
 
   call ale#linter#Reset()
 
@@ -150,6 +153,42 @@ Execute(The flake8 handler should handle names with spaces):
   \   'C:\something\with spaces.py:6:6: E111 indentation is not a multiple of four',
   \ ])
 
+Execute(Warnings about trailing whitespace should be reported by default):
+  AssertEqual
+  \ [
+  \   {
+  \     'lnum': 6,
+  \     'col': 1,
+  \     'code': 'W291',
+  \     'type': 'W',
+  \     'sub_type': 'style',
+  \     'text': 'who cares',
+  \   },
+  \   {
+  \     'lnum': 6,
+  \     'col': 1,
+  \     'code': 'W293',
+  \     'type': 'W',
+  \     'sub_type': 'style',
+  \     'text': 'who cares',
+  \   },
+  \ ],
+  \ ale_linters#python#flake8#Handle(bufnr(''), [
+  \   'foo.py:6:1: W291 who cares',
+  \   'foo.py:6:1: W293 who cares',
+  \ ])
+
+Execute(Disabling trailing whitespace warnings should work):
+  let b:ale_warn_about_trailing_whitespace = 0
+
+  AssertEqual
+  \ [
+  \ ],
+  \ ale_linters#python#flake8#Handle(bufnr(''), [
+  \   'foo.py:6:1: W291 who cares',
+  \   'foo.py:6:1: W293 who cares',
+  \ ])
+
 Execute(Warnings about trailing blank lines should be reported by default):
   AssertEqual
   \ [

test/handler/test_pycodestyle_handler.vader

@@ -1,7 +1,9 @@
 Before:
   Save g:ale_warn_about_trailing_blank_lines
+  Save g:ale_warn_about_trailing_whitespace
 
   let g:ale_warn_about_trailing_blank_lines = 1
+  let g:ale_warn_about_trailing_whitespace = 1
 
   runtime ale_linters/python/pycodestyle.vim
 
@@ -9,6 +11,7 @@ After:
   Restore
 
   unlet! b:ale_warn_about_trailing_blank_lines
+  unlet! b:ale_warn_about_trailing_whitespace
 
   call ale#linter#Reset()
   silent file something_else.py
@@ -73,6 +76,42 @@ Execute(The pycodestyle handler should parse output):
   \   'example.py:544:21: W601 .has_key() is deprecated, use ''in''',
   \ ])
 
+Execute(Warnings about trailing whitespace should be reported by default):
+  AssertEqual
+  \ [
+  \   {
+  \     'lnum': 6,
+  \     'col': 1,
+  \     'code': 'W291',
+  \     'type': 'W',
+  \     'sub_type': 'style',
+  \     'text': 'who cares',
+  \   },
+  \   {
+  \     'lnum': 6,
+  \     'col': 1,
+  \     'code': 'W293',
+  \     'type': 'W',
+  \     'sub_type': 'style',
+  \     'text': 'who cares',
+  \   },
+  \ ],
+  \ ale_linters#python#pycodestyle#Handle(bufnr(''), [
+  \   'foo.py:6:1: W291 who cares',
+  \   'foo.py:6:1: W293 who cares',
+  \ ])
+
+Execute(Disabling trailing whitespace warnings should work):
+  let b:ale_warn_about_trailing_whitespace = 0
+
+  AssertEqual
+  \ [
+  \ ],
+  \ ale_linters#python#pycodestyle#Handle(bufnr(''), [
+  \   'foo.py:6:1: W291 who cares',
+  \   'foo.py:6:1: W293 who cares',
+  \ ])
+
 Execute(Warnings about trailing blank lines should be reported by default):
   AssertEqual
   \ [