Configure ESLint RuleTester to use Typescript Parser - eslint

Question

I am trying to write some custom ESLint rules for my typescript based project. In my project I am using eslint/typescript for linting.
I have already written a custom eslint plugin which validates a custom rule. Now I want to write the unit tests for that custom rule. My test file looks like this:
/**
* #fileoverview This rule verifies that logic can only depend on other logic
* #author Dayem Siddiqui
*/
"use strict";
//------------------------------------------------------------------------------
// Requirements
//------------------------------------------------------------------------------
const typescriptParser = require('#typescript-eslint/parser')
var rule = require("../../../lib/rules/logic-dependency"),
RuleTester = require("eslint").RuleTester;
//------------------------------------------------------------------------------
// Tests
//------------------------------------------------------------------------------
typescriptParser.parseForESLint()
var ruleTester = new RuleTester({ parserOptions: {} });
ruleTester.run("logic-dependency", rule, {
valid: [
`class DeleteLogic {
}
class CreateLogic {
constructor(private deleteLogic: DeleteLogic) {}
}`
],
invalid: [
{
code: `class ExternalClient {
}
class UpdateLogic {
constructor(private externalClient: ExternalClient) {}
}`,
errors: [
{
message: "Logic cannot have a dependency on client",
type: "MethodDefinition"
}
]
}
]
});
Right now my tests a failing because by default eslint only understand plain Javascript code. I understand that I need to somehow configure it to use a custom parser that allows it to understand/parse typescript code. However I am unable to find a good example online on how to do that

Answer 1

The RuleTester constructor takes eslint's parser options that allow for configuring the parser itself. So pass it in like this and Bob's your uncle:
const ruleTester = new RuleTester({
parser: '#typescript-eslint/parser',
});
typescript-eslint's own rule tests (e.g. this one) use exactly this.
(Was searching for an answer to this question and kept up ending here, so I posted the solution I found here in the hope it'll be useful.)
eslint 6.0+
Incorporating #Sonata's comment:
Eslint 6.0+ requires an absolute path to the parser (see 6.0 migration guide):
const ruleTester = new RuleTester({
parser: require.resolve('#typescript-eslint/parser'),
});

Answer 2

Use a package such as the typescript-eslint/parser. I can't provide much more than a link in this case. If you need help using it, let me know.