ReplService.evalCode does not contribute to TypeScript's view of the scope

[abextm]

Expected Behavior

Executing code with evalCode to be equivalent to typing some code into the REPL's stdin

Actual Behavior

The REPL believes any declared variables are simultaneously not declared and already declared

Steps to reproduce the problem

const tsNode = require("ts-node");

let repl = tsNode.createRepl();
let service = tsNode.create({...repl.evalAwarePartialHost});
repl.setService(service);
repl.start();

repl.evalCode(`let foo = "bar"; console.log(foo);`);

Observe the code has been executed as bar is printed to stdout.

Enter foo into stdin, incorrectly giving
<repl>.ts:5:1 - error TS2304: Cannot find name 'foo'.
(should print bar)

Enter let foo = "baz"; into stdin giving the correct error, but with the wrong source text

<repl>.ts:1
"use strict"; void 0;
^

Uncaught SyntaxError: Identifier 'foo' has already been declared

Specifications

ts-node v10.7.0
node v18.1.0
compiler v4.6.4

• Operating system and version:
  Arch Linux

[cspotcode]

Thanks for reporting this and for including a minimal reproduction.

I think I've tracked this down:

ts-node/src/repl.ts

Line 536 in 78d103f

const isCompletion = !/\n$/.test(input);

ts-node/src/repl.ts

Lines 588 to 589 in 78d103f

	if (isCompletion) {
	undo();

The good news for you is that you have a workaround until ts-node is able to release a proper fix: be sure the string you pass to evalCode ends in a newline.