index.js 1.5 KB

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  1. 'use strict';
  2. var test = require('tape');
  3. var isString = require('../');
  4. var hasToStringTag = require('has-tostringtag/shams')();
  5. test('not Strings', function (t) {
  6. // @ts-expect-error
  7. t.notOk(isString(), 'undefined is not String');
  8. t.notOk(isString(null), 'null is not String');
  9. t.notOk(isString(false), 'false is not String');
  10. t.notOk(isString(true), 'true is not String');
  11. t.notOk(isString([]), 'array is not String');
  12. t.notOk(isString({}), 'object is not String');
  13. t.notOk(isString(function () {}), 'function is not String');
  14. t.notOk(isString(/a/g), 'regex literal is not String');
  15. t.notOk(isString(new RegExp('a', 'g')), 'regex object is not String');
  16. t.notOk(isString(new Date()), 'new Date() is not String');
  17. t.notOk(isString(42), 'number is not String');
  18. t.notOk(isString(Object(42)), 'number object is not String');
  19. t.notOk(isString(NaN), 'NaN is not String');
  20. t.notOk(isString(Infinity), 'Infinity is not String');
  21. t.end();
  22. });
  23. test('@@toStringTag', { skip: !hasToStringTag }, function (t) {
  24. /** @type {{ toString(): unknown; valueOf(): unknown; [Symbol.toStringTag]?: string; }} */
  25. var fakeString = {
  26. toString: function () { return '7'; },
  27. valueOf: function () { return '42'; }
  28. };
  29. fakeString[Symbol.toStringTag] = 'String';
  30. t.notOk(isString(fakeString), 'fake String with @@toStringTag "String" is not String');
  31. t.end();
  32. });
  33. test('Strings', function (t) {
  34. t.ok(isString('foo'), 'string primitive is String');
  35. t.ok(isString(Object('foo')), 'string object is String');
  36. t.end();
  37. });