chore: update README.md

README.md

@@ -1,32 +1,164 @@
-# ts-node-template
+# repro-y18n-default-export-broken
 
-[![standard-readme compliant](https://img.shields.io/badge/standard--readme-OK-green.svg)](https://github.com/RichardLitt/standard-readme)
+minimal reproduction of \_ .
 
-> Template project for ts-node
+## Summary
 
-## Table of Contents
+In the [`package.json`](https://github.com/yargs/y18n/blob/ad1a31b730a5034218b546e8542bb691b84992b2/package.json), the files specified in `module` and `exports` are mismatched.
 
-- [Install](#install)
-- [Usage](#usage)
-- [Contribute](#contribute)
-- [License](#license)
+- Referring `exports`, `import("y18n")` refers `./index.mjs` of y18n.
+- Referring `module`, `import("y18n")` refers `./build/lib/index.js` of y18n.
 
-## Install
+```json
+{
+  "exports": {
+    ".": [
+      {
+        "import": "./index.mjs",
+        "require": "./build/index.cjs"
+      },
+      "./build/index.cjs"
+    ]
+  },
+  "type": "module",
+  "module": "./build/lib/index.js"
+}
+```
+
+As a result, some bundler which doesn't support the `exports` field fails to build with yargs as a dependency.
+
+That's because yargs uses the default export of y18n on [`lib/platform-shims/esm.mjs`](https://github.com/yargs/yargs/blob/f37ee6f7da386a1244bf0a0c21b9572f2bb3131b/lib/platform-shims/esm.mjs),
+and [`./build/lib/index.js`](https://github.com/yargs/y18n/blob/ad1a31b730a5034218b546e8542bb691b84992b2/lib/index.ts) on y18n doesn't provide the default export.
+
+## Reproduction
 
-```bash
-$ yarn
+I created the minimum reproduction in https://github.com/tasshi-playground/repro-y18n-default-export-broken .
+
+```shell
+$ git clone [email protected]:tasshi-playground/repro-y18n-default-export-broken
+$ cd repro-y18n-default-export-broken
+$ npm install
+$ npm run build
 ```
 
-## Usage
+I examined rollup.js and Vite.
+rollup supports `exports` of package.json, and Vite doesn't support due to the bug of https://github.com/vitejs/vite/issues/11676 .
+
+- rollup refers `node_modules/y18n/index.mjs` via `exports`.
+- vite refers `node_modules/y18n/build/lib/index.js` via `module`.
+
+<details>
+<summary>Log (click to expand)</summary>
+
+### rollup.js tried to build the code `import y18n from "y18n"` (succeeded)
+
+```shell
+$ npm run build:rollup:import-default-export-of-y18n
+
+> [email protected] build:rollup:import-default-export-of-y18n
+> rollup --config ./rollup.config.default-export.mjs
+
+
+src/importing-default-export.mjs → dist...
+created dist in 49ms
 
-```bash
-$ yarn start
 ```
 
-## Contribute
+### rollup.js tried to build the code `import { y18n } from "y18n"` (failed)
 
-PRs accepted.
+```shell
+$ npm run build:rollup:import-named-export-of-y18n
+
+> [email protected] build:rollup:import-named-export-of-y18n
+> rollup --config ./rollup.config.named-export.mjs
+
+
+src/importing-named-export.mjs → dist...
+[!] RollupError: "y18n" is not exported by "node_modules/y18n/index.mjs", imported by "src/importing-named-export.mjs".
+https://rollupjs.org/guide/en/#error-name-is-not-exported-by-module
+src/importing-named-export.mjs (1:9)
+1: import { y18n } from "y18n";
+            ^
+2:
+3: console.log(y18n);
+    at error (/Users/tasshi/git/mshrtsr/repro-y18n-default-export-broken/node_modules/rollup/dist/shared/rollup.js:210:30)
+    at Module.error (/Users/tasshi/git/mshrtsr/repro-y18n-default-export-broken/node_modules/rollup/dist/shared/rollup.js:13578:16)
+    at Module.traceVariable (/Users/tasshi/git/mshrtsr/repro-y18n-default-export-broken/node_modules/rollup/dist/shared/rollup.js:13961:29)
+    at ModuleScope.findVariable (/Users/tasshi/git/mshrtsr/repro-y18n-default-export-broken/node_modules/rollup/dist/shared/rollup.js:12442:39)
+    at Identifier.bind (/Users/tasshi/git/mshrtsr/repro-y18n-default-export-broken/node_modules/rollup/dist/shared/rollup.js:8371:40)
+    at CallExpression.bind (/Users/tasshi/git/mshrtsr/repro-y18n-default-export-broken/node_modules/rollup/dist/shared/rollup.js:6165:28)
+    at CallExpression.bind (/Users/tasshi/git/mshrtsr/repro-y18n-default-export-broken/node_modules/rollup/dist/shared/rollup.js:9888:15)
+    at ExpressionStatement.bind (/Users/tasshi/git/mshrtsr/repro-y18n-default-export-broken/node_modules/rollup/dist/shared/rollup.js:6169:23)
+    at Program.bind (/Users/tasshi/git/mshrtsr/repro-y18n-default-export-broken/node_modules/rollup/dist/shared/rollup.js:6165:28)
+    at Module.bindReferences (/Users/tasshi/git/mshrtsr/repro-y18n-default-export-broken/node_modules/rollup/dist/shared/rollup.js:13574:18)
+```
+
+### Vite tried to build the code `import y18n from "y18n"` (failed)
+
+```shell
+$ npm run build:vite:import-default-export-of-y18n
+
+> [email protected] build:vite:import-default-export-of-y18n
+> vite build --config ./vite.config.default-export.mjs
+
+vite v4.0.4 building for production...
+✓ 2 modules transformed.
+"default" is not exported by "node_modules/y18n/build/lib/index.js", imported by "src/importing-default-export.mjs".
+file: /Users/tasshi/git/mshrtsr/repro-y18n-default-export-broken/src/importing-default-export.mjs:1:7
+1: import y18n from "y18n";
+          ^
+2:
+3: console.log(y18n);
+error during build:
+RollupError: "default" is not exported by "node_modules/y18n/build/lib/index.js", imported by "src/importing-default-export.mjs".
+    at error (file:///Users/tasshi/git/mshrtsr/repro-y18n-default-export-broken/node_modules/rollup/dist/es/shared/rollup.js:2041:30)
+    at Module.error (file:///Users/tasshi/git/mshrtsr/repro-y18n-default-export-broken/node_modules/rollup/dist/es/shared/rollup.js:13062:16)
+    at Module.traceVariable (file:///Users/tasshi/git/mshrtsr/repro-y18n-default-export-broken/node_modules/rollup/dist/es/shared/rollup.js:13445:29)
+    at ModuleScope.findVariable (file:///Users/tasshi/git/mshrtsr/repro-y18n-default-export-broken/node_modules/rollup/dist/es/shared/rollup.js:11926:39)
+    at Identifier.bind (file:///Users/tasshi/git/mshrtsr/repro-y18n-default-export-broken/node_modules/rollup/dist/es/shared/rollup.js:7855:40)
+    at CallExpression.bind (file:///Users/tasshi/git/mshrtsr/repro-y18n-default-export-broken/node_modules/rollup/dist/es/shared/rollup.js:5649:28)
+    at CallExpression.bind (file:///Users/tasshi/git/mshrtsr/repro-y18n-default-export-broken/node_modules/rollup/dist/es/shared/rollup.js:9372:15)
+    at ExpressionStatement.bind (file:///Users/tasshi/git/mshrtsr/repro-y18n-default-export-broken/node_modules/rollup/dist/es/shared/rollup.js:5653:23)
+    at Program.bind (file:///Users/tasshi/git/mshrtsr/repro-y18n-default-export-broken/node_modules/rollup/dist/es/shared/rollup.js:5649:28)
+    at Module.bindReferences (file:///Users/tasshi/git/mshrtsr/repro-y18n-default-export-broken/node_modules/rollup/dist/es/shared/rollup.js:13058:18)
+```
+
+### Vite tried to build the code `import { y18n } from "y18n"` (succeeded)
+
+```shell
+$ npm run build:vite:import-named-export-of-y18n
+
+> [email protected] build:vite:import-named-export-of-y18n
+> vite build --config ./vite.config.named-export.mjs
+
+vite v4.0.4 building for production...
+✓ 2 modules transformed.
+dist/importing-named-export.vite.cjs  2.84 kB │ gzip: 1.10 kB
+```
+
+</details>
+
+## Idea
+
+The file specified in the `module` field should be the same as `exports`.
+
+```diff
+{
+  "exports": {
+    ".": [
+      {
+        "import": "./index.mjs",
+        "require": "./build/index.cjs"
+      },
+      "./build/index.cjs"
+    ]
+  },
+  "type": "module",
+-   "module": "./build/lib/index.js",
++   "module": "./index.mjs",
+}
+```
 
-## License
+## Lisence
 
-MIT © mshrtsr
+This project is licensed under the [MIT license.](./LICENSE)

package.json

@@ -1,8 +1,8 @@
 {
-  "name": "ts-node-template",
+  "name": "repro-y18n-default-export-broken",
   "version": "1.0.0",
-  "main": "src/index.ts",
-  "repository": "https://[email protected]/mshrtsr/ts-node-template.git",
+  "main": "src/index.js",
+  "repository": "https://[email protected]/tasshi-playground/repro-y18n-default-export-broken.git",
   "author": "Masaharu TASHIRO <[email protected]>",
   "license": "MIT",
   "private": "true",
@@ -12,16 +12,16 @@
   "scripts": {
     "prebuild": "run-s clean",
     "build": "run-s -l -c build:rollup:* build:vite:*",
-    "build:rollup:default-export": "rollup --config ./rollup.config.default-export.mjs",
-    "build:rollup:named-export": "rollup --config ./rollup.config.named-export.mjs",
-    "build:vite:default-export": "vite build --config ./vite.config.default-export.mjs",
-    "build:vite:named-export": "vite build --config ./vite.config.named-export.mjs",
+    "build:rollup:import-default-export-of-y18n": "rollup --config ./rollup.config.default-export.mjs",
+    "build:rollup:import-named-export-of-y18n": "rollup --config ./rollup.config.named-export.mjs",
+    "build:vite:import-default-export-of-y18n": "vite build --config ./vite.config.default-export.mjs",
+    "build:vite:import-named-export-of-y18n": "vite build --config ./vite.config.named-export.mjs",
     "lint": "run-p lint:eslint lint:prettier",
     "lint:eslint": "eslint --ext .js,.mjs,.cjs,.ts,.mts,.cts ./",
     "lint:prettier": "prettier --check ./**/*.md",
     "fix": "run-s fix:eslint fix:prettier",
-    "fix:eslint": "yarn lint:eslint --fix",
-    "fix:prettier": "yarn lint:prettier --write",
+    "fix:eslint": "run-s 'lint:eslint -- --fix'",
+    "fix:prettier": "run-s 'lint:prettier -- --write'",
     "test": "echo 'no test'",
     "clean": "rimraf dist"
   },