Warning or error when importing files from a project's own outDir

Search Terms

import, outDir, composit, TS5055

Suggestion

Add a specific warning/error when trying to import something from the projects own outDir.

Use Cases

Help track down files that are wrongly importing from it's own dist directory.
I don't know if there are valid use cases where you would want to do this but I can only think of (refactor) errors.

Examples

In a big refactor I moved a class from a project to a shared directory (compiled with composite: true, imported into projects with "references").
I made the following change without thinking because it satisfied the compiler.

- import mongoose from "../../shared/dist/mongo";
+ import mongoose from "../dist/mongo";

Everything seemed to work fine (no error was shown in vscode on the import line itself, and the now shared class worked) until the next week I notice the following errors when compiling the shared dir:

error TS5055: Cannot write file '.../shared/dist/interfaces/branch.d.ts' because it would overwrite input file.
error TS5055: Cannot write ...

I did not notice these errors while doing the refactor itself because the tsc -w for the shared directory was running in a forgotten terminal tab. A warning or error on the import line itself when doing something like this would save a lot of debugging time.

Checklist

My suggestion meets these guidelines: (this is my guess, don't know exactly what the change would entail)

• This wouldn't be a breaking change in existing TypeScript/JavaScript code
• This wouldn't change the runtime behavior of existing JavaScript code
• This could be implemented without emitting different JS based on the types of the expressions
• This isn't a runtime feature (e.g. library functionality, non-ECMAScript syntax with JavaScript output, etc.)
• This feature would agree with the rest of TypeScript's Design Goals.

Das Issue nennt keine Quelldateien, Tests oder Compiler-Einstiegspunkte. Reproduziere den composite-project-Fall, indem du aus dem eigenen outDir des Projekts importierst, und verfolge dann, wie die Modulauflösung und die Diagnostik diesen Import behandeln. Erledigt ist die Aufgabe, wenn eine spezifische Warnung oder ein spezifischer Fehler auf den problematischen Import verweist und eine Regressionstestabdeckung vorhanden ist.