Before:
  let g:flow_output = {
  \ "flowVersion": "0.39.0",
  \ "errors": [
  \   {
  \     "kind": "infer",
  \     "level": "error",
  \     "message": [
  \       {
  \         "context": "  return 1",
  \         "descr": "number",
  \         "type": "Blame",
  \         "loc": {
  \           "source": "/home/w0rp/Downloads/graphql-js/src/language/parser.js",
  \           "type": "SourceFile",
  \           "start": {
  \             "line": 417,
  \             "column": 10,
  \             "offset": 9503
  \           },
  \           "end": {
  \             "line": 417,
  \             "column": 10,
  \             "offset": 9504
  \           }
  \         },
  \         "path": "/home/w0rp/Downloads/graphql-js/src/language/parser.js",
  \         "line": 417,
  \         "endline": 417,
  \         "start": 10,
  \         "end": 10
  \       },
  \       {
  \         "context": v:null,
  \         "descr": "This type is incompatible with the expected return type of",
  \         "type": "Comment",
  \         "path": "",
  \         "line": 0,
  \         "endline": 0,
  \         "start": 1,
  \         "end": 0
  \       },
  \       {
  \         "context": "function parseArguments(lexer: Lexer<*>): Array<ArgumentNode> {",
  \         "descr": "array type",
  \         "type": "Blame",
  \         "loc": {
  \           "source": "/home/w0rp/Downloads/graphql-js/src/language/parser.js",
  \           "type": "SourceFile",
  \           "start": {
  \             "line": 416,
  \             "column": 43,
  \             "offset": 9472
  \           },
  \           "end": {
  \             "line": 416,
  \             "column": 61,
  \             "offset": 9491
  \           }
  \         },
  \         "path": "/home/w0rp/Downloads/graphql-js/src/language/parser.js",
  \         "line": 416,
  \         "endline": 416,
  \         "start": 43,
  \         "end": 61
  \       }
  \     ]
  \   },
  \   {
  \     "kind": "infer",
  \     "level": "warning",
  \     "message": [
  \       {
  \         "context": "  return peek(lexer, TokenKind.PAREN_L) ?",
  \         "descr": "unreachable code",
  \         "type": "Blame",
  \         "loc": {
  \           "source": "/home/w0rp/Downloads/graphql-js/src/language/parser.js",
  \           "type": "SourceFile",
  \           "start": {
  \             "line": 419,
  \             "column": 3,
  \             "offset": 9508
  \           },
  \           "end": {
  \             "line": 421,
  \             "column": 7,
  \             "offset": 9626
  \           }
  \         },
  \         "path": "/home/w0rp/Downloads/graphql-js/src/language/parser.js",
  \         "line": 419,
  \         "endline": 421,
  \         "start": 3,
  \         "end": 7
  \       }
  \     ]
  \   }
  \ ],
  \ "passed": v:false
  \}

  runtime ale_linters/javascript/flow.vim

After:
  unlet! g:flow_output
  unlet! g:expected
  unlet! g:actual
  call ale#linter#Reset()

Execute(The flow handler should process errors correctly.):
  let g:actual = ale_linters#javascript#flow#Handle(347, [json_encode(g:flow_output)])
  let g:expected = [
  \ {
  \   'lnum': 417,
  \   'bufnr': 347,
  \   'vcol': 0,
  \   'type': 'E',
  \   'col': 10,
  \   'text': 'number: This type is incompatible with the expected return type of array type',
  \ },
  \ {
  \   'lnum': 419,
  \   'bufnr': 347,
  \   'vcol': 0,
  \   'type': 'W',
  \   'col': 3,
  \   'text': 'unreachable code:',
  \ },
  \]

  AssertEqual g:expected, g:actual