Add some VimScript lint tools (#1558)

* Add some VimScript lint tools

https://github.com/syngan/vim-vimlint
https://github.com/Kuniwak/vint

* Remove trailing newlines

* Add augroup to all autocmds

* Fix undefined variables

`l:tmpname` is never defined.

* Explicitly define global variables with g:

* Disable some vint errors

* Change has() syntax to what vimlint wants

* Disable warning for unused variables

Too much effort to fix and vimlint can't deal with closures...

* Install vint in Dockerfile

* Add 2>&1

Author: arp242

.travis.yml

@@ -1,4 +1,6 @@
 language: go
+notifications:
+  email: false
 matrix:
   include:
     - env: SCRIPT=test VIM_VERSION=vim-7.4
@@ -7,5 +9,6 @@ matrix:
     - env: SCRIPT=lint VIM_VERSION=vim-8.0
 install:
   - ./scripts/install-vim $VIM_VERSION
+  - pip install --user vim-vint
 script:
   - ./scripts/$SCRIPT $VIM_VERSION

.vintrc.yaml

@@ -0,0 +1,7 @@
+policies:
+  ProhibitUnnecessaryDoubleQuote:
+    enabled: false
+  ProhibitEqualTildeOperator:
+    enabled: false
+  ProhibitNoAbortFunction:
+    enabled: false

Dockerfile

@@ -1,7 +1,7 @@
 FROM golang:1.9.1
 
 RUN apt-get update -y && \
-  apt-get install -y build-essential curl git libncurses5-dev && \
+  apt-get install -y build-essential curl git libncurses5-dev python3-pip && \
   apt-get clean && \
   rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/*
 
@@ -14,5 +14,6 @@ WORKDIR /vim-go
 RUN scripts/install-vim vim-7.4
 RUN scripts/install-vim vim-8.0
 RUN scripts/install-vim nvim
+RUN pip3 install vim-vint
 
 ENTRYPOINT ["make"]

autoload/ctrlp/decls.vim

@@ -93,10 +93,6 @@ function! ctrlp#decls#enter() abort
     return
   endif
 
-  if exists("l:tmpname")
-    call delete(l:tmpname)
-  endif
-
   let result = eval(out)
   if type(result) != 4 || !has_key(result, 'decls')
     return

autoload/fzf/decls.vim

@@ -90,10 +90,6 @@ function! s:source(mode,...) abort
     return
   endif
 
-  if exists("l:tmpname")
-    call delete(l:tmpname)
-  endif
-
   let result = eval(out)
   if type(result) != 4 || !has_key(result, 'decls')
     return ret_decls

autoload/go/cmd.vim

@@ -14,7 +14,7 @@ function! go#cmd#Build(bang, ...) abort
   " placeholder with the current folder (indicated with '.'). We also pass -i
   " that tries to install the dependencies, this has the side effect that it
   " caches the build results, so every other build is faster.
-  let args = 
+  let args =
         \ ["build"] +
         \ map(copy(a:000), "expand(v:val)") +
         \ ["-i", ".", "errors"]

autoload/go/coverage.vim

@@ -95,9 +95,9 @@ function! go#coverage#Clear() abort
   if exists("s:toggle") | let s:toggle = 0 | endif
 
   " remove the autocmd we defined
-  if exists("#BufWinLeave#<buffer>")
-    autocmd! BufWinLeave <buffer>
-  endif
+  augroup vim-go-coverage
+    autocmd!
+  augroup end
 endfunction
 
 " Browser creates a new cover profile with 'go test -coverprofile' and opens
@@ -258,7 +258,10 @@ function! go#coverage#overlay(file) abort
   endfor
 
   " clear the matches if we leave the buffer
-  autocmd BufWinLeave <buffer> call go#coverage#Clear()
+  augroup vim-go-coverage
+    autocmd!
+    autocmd BufWinLeave <buffer> call go#coverage#Clear()
+  augroup end
 
   for m in matches
     call matchaddpos(m.group, m.pos)

autoload/go/fmt.vim

@@ -131,7 +131,7 @@ function! go#fmt#update_file(source, target)
 
   " the title information was introduced with 7.4-2200
   " https://github.com/vim/vim/commit/d823fa910cca43fec3c31c030ee908a14c272640
-  if has('patch-7.4-2200')
+  if has('patch-7.4.2200')
     " clean up previous list
     if l:listtype == "quickfix"
       let l:list_title = getqflist({'title': 1})

autoload/go/guru.vim

@@ -529,7 +529,10 @@ function! s:same_ids_highlight(exit_val, output) abort
   if get(g:, "go_auto_sameids", 0)
     " re-apply SameIds at the current cursor position at the time the buffer
     " is redisplayed: e.g. :edit, :GoRename, etc.
-    autocmd BufWinEnter <buffer> nested call go#guru#SameIds()
+    augroup vim-go-sameids
+      autocmd!
+      autocmd BufWinEnter <buffer> nested call go#guru#SameIds()
+    augroup end
   endif
 endfunction
 
@@ -551,9 +554,9 @@ function! go#guru#ClearSameIds() abort
   endif
 
   " remove the autocmds we defined
-  if exists("#BufWinEnter#<buffer>")
-    autocmd! BufWinEnter <buffer>
-  endif
+  augroup vim-go-sameids
+    autocmd!
+  augroup end
 
   return 0
 endfunction

autoload/go/list.vim

@@ -7,9 +7,9 @@ if !exists("g:go_list_type_commands")
 endif
 
 " Window opens the list with the given height up to 10 lines maximum.
-" Otherwise g:go_loclist_height is used. 
+" Otherwise g:go_loclist_height is used.
 "
-" If no or zero height is given it closes the window by default.  
+" If no or zero height is given it closes the window by default.
 " To prevent this, set g:go_list_autoclose = 0
 function! go#list#Window(listtype, ...) abort
   " we don't use lwindow to close the location list as we need also the