Correct all Vint warnings

ale_linters/haskell/ghc.vim

@@ -22,14 +22,14 @@ function! ale_linters#haskell#ghc#Handle(buffer, lines)
     for line in a:lines
         if len(matchlist(line, pattern)) > 0
             call add(corrected_lines, line)
-            if line !~ ': error:$'
+            if line !~# ': error:$'
                 call add(corrected_lines, '')
             endif
-        elseif line == ''
+        elseif line ==# ''
             call add(corrected_lines, line)
         else
             if len(corrected_lines) > 0
-                if corrected_lines[-1] =~ ': error:$'
+                if corrected_lines[-1] =~# ': error:$'
                     let line = substitute(line, '\v^\s+', ' ', '')
                 endif
                 let corrected_lines[-1] .= line

ale_linters/scala/scalac.vim

@@ -25,7 +25,7 @@ function! ale_linters#scala#scalac#Handle(buffer, lines)
         endif
 
         let text = l:match[3]
-        let type = l:match[2] == 'error' ? 'E' : 'W'
+        let type = l:match[2] ==# 'error' ? 'E' : 'W'
         let col = 0
         if ln + 1 < len(a:lines)
             let col = stridx(a:lines[ln + 1], '^')

ale_linters/sh/shellcheck.vim

@@ -16,7 +16,7 @@ if !exists('g:ale_linters_sh_shellcheck_exclusions')
     let g:ale_linters_sh_shellcheck_exclusions = ''
 endif
 
-if g:ale_linters_sh_shellcheck_exclusions != ''
+if g:ale_linters_sh_shellcheck_exclusions !=# ''
     let s:exclude_option = '-e ' .  g:ale_linters_sh_shellcheck_exclusions
 else
     let s:exclude_option = ''

plugin/ale/zmain.vim

@@ -107,7 +107,7 @@ function! s:FixLoclist(buffer, loclist)
 endfunction
 
 function! s:HandleExit(job)
-    if a:job == 'no process'
+    if a:job ==# 'no process'
         " Stop right away when the job is not valid in Vim 8.
         return
     endif
@@ -249,7 +249,7 @@ function! s:ApplyLinter(buffer, linter)
     endif
 
     " Only proceed if the job is being run.
-    if has('nvim') || (job != 'no process' && job_status(job) == 'run')
+    if has('nvim') || (job !=# 'no process' && job_status(job) ==# 'run')
         let a:linter.job = job
 
         " Store the ID for the job in the map to read back again.
@@ -271,7 +271,7 @@ function! s:ApplyLinter(buffer, linter)
             let input = join(getbufline(a:buffer, 1, '$'), "\n") . "\n"
             let channel = job_getchannel(job)
 
-            if ch_status(channel) == 'open'
+            if ch_status(channel) ==# 'open'
                 call ch_sendraw(channel, input)
                 call ch_close_in(channel)
             endif