Add an option for ignoring the output of TSLint if a file contains a single blank line

ale_linters/typescript/tslint.vim

@@ -5,6 +5,7 @@ call ale#Set('typescript_tslint_executable', 'tslint')
 call ale#Set('typescript_tslint_config_path', '')
 call ale#Set('typescript_tslint_rules_dir', '')
 call ale#Set('typescript_tslint_use_global', 0)
+call ale#Set('typescript_tslint_ignore_empty_files', 0)
 
 function! ale_linters#typescript#tslint#GetExecutable(buffer) abort
     return ale#node#FindExecutable(a:buffer, 'typescript_tslint', [
@@ -13,6 +14,12 @@ function! ale_linters#typescript#tslint#GetExecutable(buffer) abort
 endfunction
 
 function! ale_linters#typescript#tslint#Handle(buffer, lines) abort
+    " Do not output any errors for empty files if the option is on.
+    if ale#Var(a:buffer, 'typescript_tslint_ignore_empty_files')
+    \&& getbufline(a:buffer, 1, '$') == ['']
+        return []
+    endif
+
     let l:dir = expand('#' . a:buffer . ':p:h')
     let l:output = []
 

doc/ale-typescript.txt

@@ -30,6 +30,18 @@ g:ale_typescript_tslint_config_path       *g:ale_typescript_tslint_config_path*
   such path exists, this variable will be used instead.
 
 
+g:ale_typescript_tslint_ignore_empty_files
+                                   *g:ale_typescript_tslint_ignore_empty_files*
+                                   *b:ale_typescript_tslint_ignore_empty_files*
+  Type: |Number|
+  Default: `0`
+
+  When set to `1`, ALE will not report any problems for empty files with
+  TSLint. ALE will still execute TSLint for the files, but ignore any problems
+  reported. This stops ALE from complaining about newly created files,
+  and files where lines have been added and then removed.
+
+
 g:ale_typescript_tslint_rules_dir           *g:ale_typescript_tslint_rules_dir*
                                             *b:ale_typescript_tslint_rules_dir*
   Type: |String|

test/handler/test_tslint_handler.vader

@@ -1,9 +1,18 @@
 Before:
+  Save g:ale_typescript_tslint_ignore_empty_files
+
+  unlet! g:ale_typescript_tslint_ignore_empty_files
+  unlet! b:ale_typescript_tslint_ignore_empty_files
+
   runtime ale_linters/typescript/tslint.vim
 
   call ale#test#SetDirectory('/testplugin/test/handler')
 
 After:
+  Restore
+
+  unlet! b:ale_typescript_tslint_ignore_empty_files
+
   call ale#test#RestoreDirectory()
   call ale#linter#Reset()
 
@@ -133,3 +142,113 @@ Execute(The tslint handler should handle empty output):
   AssertEqual
   \ [],
   \ ale_linters#typescript#tslint#Handle(bufnr(''), [])
+
+Execute(The tslint handler report errors for empty files by default):
+  call ale#test#SetFilename('app/test.ts')
+
+  AssertEqual
+  \ [
+  \   {
+  \     'lnum': 2,
+  \     'col': 1,
+  \     'filename': expand('%:p:h') . '/test.ts',
+  \     'end_lnum': 2,
+  \     'type': 'E',
+  \     'end_col': 1,
+  \     'text': 'no-consecutive-blank-lines: Consecutive blank lines are forbidden',
+  \   },
+  \ ],
+  \ ale_linters#typescript#tslint#Handle(bufnr(''), [json_encode([{
+  \   'endPosition': {
+  \     'character': 0,
+  \     'line': 1,
+  \     'position': 1
+  \   },
+  \   'failure': 'Consecutive blank lines are forbidden',
+  \   'fix': [{
+  \     'innerStart': 0,
+  \     'innerLength': 1,
+  \     'innerText': ''
+  \   }],
+  \   'name': 'test.ts',
+  \   'ruleName': 'no-consecutive-blank-lines',
+  \   'ruleSeverity': 'ERROR',
+  \   'startPosition': {
+  \     'character': 0,
+  \     'line': 1,
+  \     'position': 1
+  \   }
+  \ }])])
+
+Execute(The tslint handler should not report errors for empty files when the ignore option is on):
+  let b:ale_typescript_tslint_ignore_empty_files = 1
+  call ale#test#SetFilename('app/test.ts')
+
+  AssertEqual
+  \ [
+  \ ],
+  \ ale_linters#typescript#tslint#Handle(bufnr(''), [json_encode([{
+  \   'endPosition': {
+  \     'character': 0,
+  \     'line': 1,
+  \     'position': 1
+  \   },
+  \   'failure': 'Consecutive blank lines are forbidden',
+  \   'fix': [{
+  \     'innerStart': 0,
+  \     'innerLength': 1,
+  \     'innerText': ''
+  \   }],
+  \   'name': 'test.ts',
+  \   'ruleName': 'no-consecutive-blank-lines',
+  \   'ruleSeverity': 'ERROR',
+  \   'startPosition': {
+  \     'character': 0,
+  \     'line': 1,
+  \     'position': 1
+  \   }
+  \ }])])
+
+Given typescript(A file with extra blank lines):
+  const x = 3
+
+
+  const y = 4
+
+Execute(The tslint handler should report errors when the ignore option is on, but the file is not empty):
+  let b:ale_typescript_tslint_ignore_empty_files = 1
+  call ale#test#SetFilename('app/test.ts')
+
+  AssertEqual
+  \ [
+  \   {
+  \     'lnum': 2,
+  \     'col': 1,
+  \     'filename': expand('%:p:h') . '/test.ts',
+  \     'end_lnum': 2,
+  \     'type': 'E',
+  \     'end_col': 1,
+  \     'text': 'no-consecutive-blank-lines: Consecutive blank lines are forbidden',
+  \   },
+  \ ],
+  \ ale_linters#typescript#tslint#Handle(bufnr(''), [json_encode([{
+  \   'endPosition': {
+  \     'character': 0,
+  \     'line': 1,
+  \     'position': 1
+  \   },
+  \   'failure': 'Consecutive blank lines are forbidden',
+  \   'fix': [{
+  \     'innerStart': 0,
+  \     'innerLength': 1,
+  \     'innerText': ''
+  \   }],
+  \   'name': 'test.ts',
+  \   'ruleName': 'no-consecutive-blank-lines',
+  \   'ruleSeverity': 'ERROR',
+  \   'startPosition': {
+  \     'character': 0,
+  \     'line': 1,
+  \     'position': 1
+  \   }
+  \ }])])