Switch from TSLint to typescript-eslint

[JoshuaKGoldberg]

This repository still uses TSLint, which is being deprecated: palantir/tslint#4534. It'd be great to move it over to typescript-eslint to no longer use deprecated packages.

Protip: tslint-to-eslint-config is the recommended package to do so!

[arvidboivie]

I'm having a go at this!

[arvidboivie]

I'm having issues running verify on the project, even without any changes. I'm probably missing something easy, and don't want to go making changes to get this working. The tests are failing, here's the output:

 FAIL  src/shared/NameGenerator.test.ts
  ● Test suite failed to run

    Jest encountered an unexpected token

    This usually means that you are trying to import a file which Jest cannot parse, e.g. it's not plain JavaScript.

    By default, if Jest sees a Babel config, it will use that to transform your files, ignoring "node_modules".

    Here's what you can do:
     • To have some of your "node_modules" files transformed, you can specify a custom "transformIgnorePatterns" in your config.
     • If you need a custom transformation specify a "transform" option in your config.
     • If you simply want to mock your non-JS modules (e.g. binary assets) you can stub them out with the "moduleNameMapper" config option.

    You'll find more details and examples of these config options in the docs:
    https://jestjs.io/docs/en/configuration.html

    Details:

    /Users/arbo/repos/hacktoberfest/TypeStat/src/shared/NameGenerator.ts:12
      countsPerBase = new Map();
                    ^

    SyntaxError: Unexpected token =

    > 1 | import { NameGenerator } from "./NameGenerator";
        | ^
      2 |
      3 | describe("NameGenerator", () => {
      4 |     it("creates a basic name when the base portion hasn't been requested yet", () => {

      at ScriptTransformer._transformAndBuildScript (node_modules/@jest/transform/build/ScriptTransformer.js:537:17)
      at ScriptTransformer.transform (node_modules/@jest/transform/build/ScriptTransformer.js:579:25)
      at Object.<anonymous> (src/shared/NameGenerator.test.ts:1:1)

 FAIL  src/cli/runCli.test.ts
  ● Test suite failed to run

    Jest encountered an unexpected token

    This usually means that you are trying to import a file which Jest cannot parse, e.g. it's not plain JavaScript.

    By default, if Jest sees a Babel config, it will use that to transform your files, ignoring "node_modules".

    Here's what you can do:
     • To have some of your "node_modules" files transformed, you can specify a custom "transformIgnorePatterns" in your config.
     • If you need a custom transformation specify a "transform" option in your config.
     • If you simply want to mock your non-JS modules (e.g. binary assets) you can stub them out with the "moduleNameMapper" config option.

    You'll find more details and examples of these config options in the docs:
    https://jestjs.io/docs/en/configuration.html

    Details:

    /Users/arbo/repos/hacktoberfest/TypeStat/src/shared/FileInfoCache.ts:17
      nodeReferences = new Map();
                     ^

    SyntaxError: Unexpected token =

      4 | import { TypeStatOptions } from "../../options/types";
      5 | import { LazyCache } from "../../services/LazyCache";
    > 6 | import { FileInfoCache } from "../../shared/FileInfoCache";
        | ^
      7 | import { convertMapToObject, Dictionary } from "../../shared/maps";
      8 | import { NameGenerator } from "../../shared/NameGenerator";
      9 | import { collectFilteredNodes } from "../collectFilteredNodes";

      at ScriptTransformer._transformAndBuildScript (node_modules/@jest/transform/build/ScriptTransformer.js:537:17)
      at ScriptTransformer.transform (node_modules/@jest/transform/build/ScriptTransformer.js:579:25)
      at Object.<anonymous> (src/runtime/providers/createCoreMutationsProvider.ts:6:1)

[JoshuaKGoldberg]

Oh 😦 I don't get those errors locally on a fresh clone @arvidboivie, working on Windows. Maybe the issue is Mac/*nix specific?

Anyway, you can ignore them - you shouldn't need to run yarn run verify for this issue. Just running yarn run eslint after it's created should be sufficient. Does that help?

[arvidboivie]

@JoshuaKGoldberg You're right, I skipped looking at those errors. Probably Mac related. Tried my hand at replacing the rules, PR up now.

[JoshuaKGoldberg]

Fixed by #371.