Execute(TypeScript completions responses should be parsed correctly):
  AssertEqual [],
  \ ale#completion#ParseTSServerCompletions({
  \ 'body': [],
  \})
  AssertEqual ['foo', 'bar', 'baz'],
  \ ale#completion#ParseTSServerCompletions({
  \ 'body': [
  \   {'name': 'foo'},
  \   {'name': 'bar'},
  \   {'name': 'baz'},
  \ ],
  \})

Execute(TypeScript completion details responses should be parsed correctly):
  AssertEqual
  \ [
  \   {
  \     'word': 'abc',
  \     'menu': '(property) Foo.abc: number',
  \     'info': '',
  \     'kind': 'f'
  \   },
  \   {
  \     'word': 'def',
  \     'menu': '(property) Foo.def: number',
  \     'info': 'foo bar baz',
  \     'kind': 'f'
  \   },
  \ ],
  \ ale#completion#ParseTSServerCompletionEntryDetails({
  \ 'body': [
  \   {
  \     'name': 'abc',
  \     'kind': 'parameterName',
  \     'displayParts': [
  \       {'text': '('},
  \       {'text': 'property'},
  \       {'text': ')'},
  \       {'text': ' '},
  \       {'text': 'Foo'},
  \       {'text': '.'},
  \       {'text': 'abc'},
  \       {'text': ':'},
  \       {'text': ' '},
  \       {'text': 'number'},
  \     ],
  \   },
  \   {
  \     'name': 'def',
  \     'kind': 'parameterName',
  \     'displayParts': [
  \       {'text': '('},
  \       {'text': 'property'},
  \       {'text': ')'},
  \       {'text': ' '},
  \       {'text': 'Foo'},
  \       {'text': '.'},
  \       {'text': 'def'},
  \       {'text': ':'},
  \       {'text': ' '},
  \       {'text': 'number'},
  \     ],
  \     'documentation': [
  \       {'text': 'foo'},
  \       {'text': ' '},
  \       {'text': 'bar'},
  \       {'text': ' '},
  \       {'text': 'baz'},
  \     ],
  \   },
  \ ],
  \})

Given typescript():
  let abc = y.
  let foo = ab
  let foo = (ab)

Execute(Completion should be done after dots in TypeScript):
  AssertEqual '.', ale#completion#GetPrefix(&filetype, 1, 13)

Execute(Completion should be done after words in TypeScript):
  AssertEqual 'ab', ale#completion#GetPrefix(&filetype, 2, 13)

Execute(Completion should be done after words in parens in TypeScript):
  AssertEqual 'ab', ale#completion#GetPrefix(&filetype, 3, 14)

Execute(Completion should not be done after parens in TypeScript):
  AssertEqual '', ale#completion#GetPrefix(&filetype, 3, 15)