Converting jest test to typescript: SyntaxError: Cannot use import statement outside a module

I was following the simple and well-written docs from jest, and I got this test working properly:

const { spawnSync } = require('child_process');

const ls = spawnSync('ls', ['-lh', '/usr']);
const unexistent = spawnSync('thiscommandshouldnotexist', ['-lh', '/']);

test('spawnSync1', () => {
    expect(ls.error).toBe(undefined);
});
test('spawnSync2', () => {
    expect(unexistent.error).not.toBe(undefined);
});

Now, I wanted to switch to typescript, so I renamed the above file to have .ts extension, invoked yarn add --dev ts-jest (because I prefer to not use Babel) in the command line, and added this import as advised in the docs: import {describe, expect, test} from '@jest/globals';

However, after doing the above, I get this error message when calling yarn jest:

/Users/knocte/Documents/Code/myrepo/somefilename.test.ts:1 ({"Object.":function(module,exports,require,__dirname,__filename,jest){import { describe, expect, test } from '@jest/globals'; SyntaxError: Cannot use import statement outside a module at Runtime.createScriptFromCode (node_modules/jest-runtime/build/index.js:1678:14)

Am I following the guide in a wrong way? Did I miss any step? In the guide, there's no module defined in the code snippet.

UPDATE: I've tried running the commands yarn add --dev ts-node and yarn jest --init, to no avail, yielding this new error message:

% yarn jest
yarn run v1.22.19
$ /Users/knocte/Documents/Code/myrepo/node_modules/.bin/jest
Error: Jest: Failed to parse the TypeScript config file /Users/knocte/Documents/Code/myrepo/jest.config.ts
  Error: Cannot find module 'typescript'
Require stack:
- /Users/knocte/Documents/Code/myrepo/node_modules/ts-node/dist/util.js
- /Users/knocte/Documents/Code/myrepo/node_modules/ts-node/dist/index.js
    at readConfigFileAndSetRootDir (/Users/knocte/Documents/Code/myrepo/node_modules/jest-config/build/readConfigFileAndSetRootDir.js:136:13)
    at async readConfig (/Users/knocte/Documents/Code/myrepo/node_modules/jest-config/build/index.js:216:18)
    at async readConfigs (/Users/knocte/Documents/Code/myrepo/node_modules/jest-config/build/index.js:404:26)
    at async runCLI (/Users/knocte/Documents/Code/myrepo/node_modules/@jest/core/build/cli/index.js:182:59)
    at async Object.run (/Users/knocte/Documents/Code/myrepo/node_modules/jest-cli/build/cli/index.js:155:37)
error Command failed with exit code 1.
info Visit https://yarnpkg.com/en/docs/cli/run for documentation about this command.