When relatively importing a `.d.ts` file in a declaration file, TypeScript loads a `.ts` file instead

🔎 Search Terms

• module resolution
• probing

🕗 Version & Regression Information

TypeScript 5.4.3

⏯ Playground Link

No response

💻 Code

// package.json
{
  "name": "test4",
  "dependencies": {
    "@std/fs": "npm:@jsr/std__fs@^0.224.0"
  }
}

// package-lock.json
{
  "name": "test4",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "dependencies": {
        "@std/fs": "npm:@jsr/std__fs@^0.224.0"
      }
    },
    "node_modules/@jsr/std__assert": {
      "version": "0.224.0",
      "resolved": "https://npm.jsr.io/~/8/@jsr/std__assert/0.224.0.tgz",
      "integrity": "sha512-2JTYGKyQ9Rb9NEalTJIN3LZ5NaDuoOpHesqP1+5sjjTXVYkzLgDoykjaFwWBJ+70YIg2Tctkj1xoaG0ga7tzsg==",
      "dependencies": {
        "@jsr/std__fmt": "^0.224.0",
        "@jsr/std__internal": "^0.224.0"
      }
    },
    "node_modules/@jsr/std__fmt": {
      "version": "0.224.0",
      "resolved": "https://npm.jsr.io/~/8/@jsr/std__fmt/0.224.0.tgz",
      "integrity": "sha512-rj0m00LslTlQJyXmkWe114v9aSbK81B33VcgIrYaaRuE7DTiFe6cebkNGQdAPQemLC4vRqiQMOZ247GdFFhk4g=="
    },
    "node_modules/@jsr/std__internal": {
      "version": "0.224.0",
      "resolved": "https://npm.jsr.io/~/8/@jsr/std__internal/0.224.0.tgz",
      "integrity": "sha512-pinRPGlSqi0qgFGDs1LUJ8vIe0p1jh6SIt2b02266a4OIO7RSTQiZNd21PV9UIFuJbaNTsskhGzqlN2ePvPU0Q==",
      "dependencies": {
        "@jsr/std__fmt": "^0.224.0"
      }
    },
    "node_modules/@jsr/std__path": {
      "version": "0.224.0",
      "resolved": "https://npm.jsr.io/~/8/@jsr/std__path/0.224.0.tgz",
      "integrity": "sha512-E8Nyv8dox8vR5wbA4FS7wMlSctZ6L1CVwshMrNLgFUqcCOE3VCvjKokgXs43sJEcq3w8aIY62j/mDxeFIOvwvA==",
      "dependencies": {
        "@jsr/std__assert": "^0.224.0"
      }
    },
    "node_modules/@std/fs": {
      "name": "@jsr/std__fs",
      "version": "0.224.0",
      "resolved": "https://npm.jsr.io/~/8/@jsr/std__fs/0.224.0.tgz",
      "integrity": "sha512-z7dnRgqDlgqnm9P0oJYiur0uFmKoQ5zOujbm5X+KwbJb6cnmpw7PrzMroq3PWy0kNOkGMLb0AU3IlENa+cVmTA==",
      "dependencies": {
        "@jsr/std__assert": "^0.224.0",
        "@jsr/std__path": "^0.224.0"
      }
    }
  }
}

$ npm i

// tsconfig.json
{
  "compilerOptions": {
    "module": "esnext",
    "moduleResolution": "bundler"
  }
}

// index.ts
import { walk } from "@std/fs/walk";

🙁 Actual behavior

$ tsc --explainFiles
node_modules/@std/fs/_create_walk_entry.ts:12:36 - error TS2503: Cannot find namespace 'Deno'.

12 export interface WalkEntry extends Deno.DirEntry {
                                      ~~~~

node_modules/@std/fs/_create_walk_entry.ts:22:16 - error TS2304: Cannot find name 'Deno'.

22   const info = Deno.statSync(path);
                  ~~~~

node_modules/@std/fs/_create_walk_entry.ts:25:5 - error TS2353: Object literal may only specify known properties, and 'name' does not exist in type 'WalkEntry'.

25     name,
       ~~~~

node_modules/@std/fs/_create_walk_entry.ts:33:60 - error TS2705: An async function or method in ES5/ES3 requires the 'Promise' constructor.  Make sure you have a declaration for the 'Promise' constructor or include 'ES2015' in your '--lib' option.

33 export async function createWalkEntry(path: string | URL): Promise<WalkEntry> {
                                                              ~~~~~~~~~~~~~~~~~~

node_modules/@std/fs/_create_walk_entry.ts:37:22 - error TS2304: Cannot find name 'Deno'.

37   const info = await Deno.stat(path);
                        ~~~~

node_modules/@std/fs/_create_walk_entry.ts:40:5 - error TS2353: Object literal may only specify known properties, and 'name' does not exist in type 'WalkEntry'.

40     name,
       ~~~~

node_modules/@std/fs/walk.d.ts:1:32 - error TS2846: A declaration file cannot be imported without 'import type'. Did you mean to import an implementation file './_create_walk_entry.js' instead?

1 import { type WalkEntry } from "./_create_walk_entry.d.ts";
                                 ~~~~~~~~~~~~~~~~~~~~~~~~~~~

node_modules/@std/fs/walk.d.ts:99:73 - error TS2583: Cannot find name 'AsyncIterableIterator'. Do you need to change your target library? Try changing the 'lib' compiler option to 'es2018' or later.

99  */ export declare function walk(root: string | URL, {}?: WalkOptions): AsyncIterableIterator<WalkEntry>;
                                                                           ~~~~~~~~~~~~~~~~~~~~~

node_modules/@std/fs/walk.d.ts:100:130 - error TS2304: Cannot find name 'IterableIterator'.

100 /** Same as {@linkcode walk} but uses synchronous ops */ export declare function walkSync(root: string | URL, {}?: WalkOptions): IterableIterator<WalkEntry>;
                                                                                                                                     ~~~~~~~~~~~~~~~~

../../../../.config/yarn/global/node_modules/typescript/lib/lib.d.ts
  Default library for target 'es5'
../../../../.config/yarn/global/node_modules/typescript/lib/lib.es5.d.ts
  Library referenced via 'es5' from file '../../../../.config/yarn/global/node_modules/typescript/lib/lib.d.ts'
../../../../.config/yarn/global/node_modules/typescript/lib/lib.dom.d.ts
  Library referenced via 'dom' from file '../../../../.config/yarn/global/node_modules/typescript/lib/lib.d.ts'
../../../../.config/yarn/global/node_modules/typescript/lib/lib.webworker.importscripts.d.ts
  Library referenced via 'webworker.importscripts' from file '../../../../.config/yarn/global/node_modules/typescript/lib/lib.d.ts'
../../../../.config/yarn/global/node_modules/typescript/lib/lib.scripthost.d.ts
  Library referenced via 'scripthost' from file '../../../../.config/yarn/global/node_modules/typescript/lib/lib.d.ts'
../../../../.config/yarn/global/node_modules/typescript/lib/lib.decorators.d.ts
  Library referenced via 'decorators' from file '../../../../.config/yarn/global/node_modules/typescript/lib/lib.es5.d.ts'
../../../../.config/yarn/global/node_modules/typescript/lib/lib.decorators.legacy.d.ts
  Library referenced via 'decorators.legacy' from file '../../../../.config/yarn/global/node_modules/typescript/lib/lib.es5.d.ts'
node_modules/@jsr/std__path/basename.d.ts
  Imported via "@jsr/std__path/basename" from file 'node_modules/@std/fs/_create_walk_entry.ts' with packageId '@jsr/std__path/basename.d.ts@0.224.0'
node_modules/@jsr/std__path/normalize.d.ts
  Imported via "@jsr/std__path/normalize" from file 'node_modules/@std/fs/_create_walk_entry.ts' with packageId '@jsr/std__path/normalize.d.ts@0.224.0'
node_modules/@jsr/std__path/from_file_url.d.ts
  Imported via "@jsr/std__path/from-file-url" from file 'node_modules/@std/fs/_to_path_string.ts' with packageId '@jsr/std__path/from_file_url.d.ts@0.224.0'
node_modules/@std/fs/_to_path_string.ts
  Imported via "./_to_path_string.js" from file 'node_modules/@std/fs/_create_walk_entry.ts' with packageId '@jsr/std__fs/_to_path_string.ts@0.224.0'
node_modules/@std/fs/_create_walk_entry.ts
  Imported via "./_create_walk_entry.d.ts" from file 'node_modules/@std/fs/walk.d.ts' with packageId '@jsr/std__fs/_create_walk_entry.ts@0.224.0'
node_modules/@std/fs/walk.d.ts
  Imported via "@std/fs/walk" from file 'index.ts' with packageId '@jsr/std__fs/walk.d.ts@0.224.0'
index.ts
  Matched by default include pattern '**/*'

Found 9 errors in 2 files.

Errors  Files
     6  node_modules/@std/fs/_create_walk_entry.ts:12
     3  node_modules/@std/fs/walk.d.ts:1

From the walk.d.ts file (referenced specified in package.json "types" conditional export), a type is imported from ./_create_walk_entry.d.ts. TypeScript however does not load ./_create_walk_entry.d.ts, but instead loads ./_create_walk_entry.ts (and then tries to check it) even though ./_create_walk_entry.d.ts exists. Why?

The .ts files are included in the published package to enable "Go to source definition" for users. Is it really necessary to place all generated files into a separate directory?

🙂 Expected behavior

No .ts file to be loaded, because all specifiers (both in conditional exports, and in declaration files) reference .d.ts files.

This is especially the case because when declaration: true is specified, TypeScript will by default place .js and .d.ts directly next to the .ts code. If you publish this to npm, it will not work.

Additional information about the issue

No response