Source code transpiles, but emitted declarations filled with errors

I apologize if I shouldn’t be opening an issue about this.

I asked about debugging long compile times before in another issue, #24435

This issue right now is related to that but in a different way.

The typed-orm project transpiles quickly now, after an unintuitive solution, but the emitted declarations appear “unusable” by other projects (at least according to tsc).

ts-node and VS code don’t seem to have a problem with the emitted declarations and seem to run just fine.

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TypeScript Version: 2.9.1

Search Terms: emit declarations incorrect

Code

import * as o from "typed-orm";
o;

And then run tsc --noEmit --diagnostics

A repo that reproduces the problem can be found here

Expected behavior:

Success after about 17 seconds

Actual behavior:

Errors after about 37s

The list of errors is… Rather large.

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I have a different project that is using typed-orm and ts-node seems to run it fine. VS code also seems to do some type checking fine (seems to, maybe it skips some more involved checks, or does incremental checking, I have no idea).

However, when I try to run tsc (checking types/transpiling), node just runs out of memory, even after giving it 8GB of RAM.

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I tried to debug what was wrong. The typed-orm project itself transpiles very quickly, now. I figured there must be something wrong with that project. However, after removing a lot of code, I still got out-of-memory exceptions.

In the end, I created an entirely new project, wrote that snippet above, and saw that even though the source code for typed-orm transpiles, the transpiled declarations seem to have errors.

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Link to example: here

Link to typed-orm: here

Related Issues: #24435

[weswigham]

Actually, I’m pretty sure those paths are the expected and desired output when baseUrl is set, given that baseUrl is for multiproject/application scenarios (so you say baseUrl is your workspace root, then use nonrelative paths for each workspace folder). Why do you have baseUrl set in your tsconfig; with a quick look I can’t find any paths in your application that should rely on it to work?

[AnyhowStep]

Random question; are these types the same? (They seem to be)

X extends Y ? Extract<X, Y> : never

And

Extract<X, Y>