Tsconfig option to disable .tsx extension lookup in module resolution

Suggestion

Running tsc --traceResolution in my project I found that Typescript was looking up .tsx files for every module resolution. That's very inconvenient, first because .tsx extension serves a very specific domain, second because by elliminating hundreds or maybe thousands of (think of a really big project) unecessary stat() syscalls the build time would probably speed up a bit, or maybe considerably.

🔍 Search Terms

• tsx
• module resolution

✅ Viability Checklist

My suggestion meets these guidelines:

• 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, new syntax sugar for JS, etc.)
• This feature would agree with the rest of TypeScript's Design Goals.

Start with tsc --traceResolution to observe the current module-resolution probes for .tsx files. Trace the module-resolution entry points and determine how a tsconfig option would control those probes without changing existing defaults. Done means the option suppresses .tsx lookup when enabled while normal resolution remains unchanged otherwise.