Option to write exports to jsr.json

README.md

@@ -461,6 +461,21 @@ With this addition, `zshy` will add the `"my-source"` condition to the generated
 }
 ```
 
+### JSR
+
+For packages that also publish to [JSR](https://jsr.io/), you can have `zshy` copy your configured exports to `jsr.json`, making your `zshy` configuration the single source of truth for exports:
+
+```jsonc
+{
+  "zshy": {
+    "exports": { ... },
+    "jsr": true
+  }
+}
+```
+
+This will copy over the paths of the source code entrypoints, not the paths to the transpiled code, since JSR supports and encourages publishing TypeScript source code rather than pairs of `.js` + `.d.ts` files.
+
 <br/>
 <br/>
 <br/>
@@ -686,7 +701,7 @@ To learn more, read the ["Masquerading as CJS"](https://github.com/arethetypeswr
 
 ```ts
 function hello() {
-  console.log('hello');
+  console.log("hello");
 }
 
 export default hello;
@@ -696,7 +711,7 @@ export default hello;
 
 ```ts
 function hello() {
-  console.log('hello');
+  console.log("hello");
 }
 exports.default = hello;
 module.exports = exports.default;

src/main.ts

@@ -6,6 +6,8 @@ import { table } from "table";
 import * as ts from "typescript";
 import { type BuildContext, compileProject } from "./compile.js";
 import {
+  detectConfigIndention,
+  findConfigPath,
   formatForLog,
   isSourceFile,
   isTestFile,
@@ -24,6 +26,7 @@ interface RawConfig {
   conditions?: Record<string, "esm" | "cjs" | "src">;
   tsconfig?: string; // optional path to tsconfig.json file
   noEdit?: boolean;
+  jsr?: boolean;
 }
 
 interface NormalizedConfig {
@@ -33,6 +36,7 @@ interface NormalizedConfig {
   cjs: boolean;
   tsconfig: string;
   noEdit: boolean;
+  jsr: boolean;
 }
 
 export async function main(): Promise<void> {
@@ -163,36 +167,15 @@ Examples:
   ///////////////////////////////////
 
   // Find package.json by scanning up the file system
-  let packageJsonPath = "./package.json";
-  let currentDir = process.cwd();
-
-  while (currentDir !== path.dirname(currentDir)) {
-    const candidatePath = path.join(currentDir, "package.json");
-    if (fs.existsSync(candidatePath)) {
-      packageJsonPath = candidatePath;
-      break;
-    }
-    currentDir = path.dirname(currentDir);
-  }
-
-  if (!fs.existsSync(packageJsonPath)) {
-    log.error("❌ package.json not found in current directory or any parent directories");
-    process.exit(1);
-  }
+  const packageJsonPath = findConfigPath("package.json");
 
   // read package.json and extract the "zshy" exports config
   const pkgJsonRaw = fs.readFileSync(packageJsonPath, "utf-8");
   // console.log("📦 Extracting entry points from package.json exports...");
   const pkgJson = JSON.parse(pkgJsonRaw);
 
   // Detect indentation from package.json to preserve it.
-  let indent: string | number = 2; // Default to 2 spaces
-  const indentMatch = pkgJsonRaw.match(/^([ \t]+)/m);
-  if (indentMatch?.[1]) {
-    indent = indentMatch[1];
-  } else if (!pkgJsonRaw.includes("\n")) {
-    indent = 0; // minified
-  }
+  const pkgJsonIndent = detectConfigIndention(pkgJsonRaw);
 
   const pkgJsonDir = path.dirname(packageJsonPath);
   const pkgJsonRelPath = relativePosix(pkgJsonDir, packageJsonPath);
@@ -285,11 +268,14 @@ Examples:
 
   const config = { ...rawConfig } as NormalizedConfig;
 
+  // Normalize boolean options
+  config.noEdit ??= false;
+  config.jsr ??= false;
+
   // Normalize cjs property
   if (config.cjs === undefined) {
     config.cjs = true; // Default to true if not specified
   }
-  config.noEdit ??= false;
 
   // Validate that if cjs is disabled, no conditions are set to "cjs"
   if (config.cjs === false && config.conditions) {
@@ -1045,7 +1031,48 @@ Examples:
       ///////////////////////////////
       log.info("[dryrun] Skipping package.json modification");
     } else {
-      fs.writeFileSync(packageJsonPath, JSON.stringify(pkgJson, null, indent) + "\n");
+      fs.writeFileSync(packageJsonPath, JSON.stringify(pkgJson, null, pkgJsonIndent) + "\n");
+    }
+  }
+
+  //////////////////////////////////
+  ///     write jsr exports      ///
+  //////////////////////////////////
+
+  if (config.jsr) {
+    if (!isSilent) {
+      log.info(`${prefix}Updating jsr.json...`);
+    }
+
+    // Find jsr.json by scanning up the file system
+    const jsrJsonPath = findConfigPath("jsr.json");
+
+    // read jsr.json
+    const jsrJsonRaw = fs.readFileSync(jsrJsonPath, "utf-8");
+    const jsrJson = JSON.parse(jsrJsonRaw);
+
+    // Detect indentation from jsr.json to preserve it.
+    const jsrJsonIndent = detectConfigIndention(jsrJsonRaw);
+
+    const jsrJsonDir = path.dirname(jsrJsonPath);
+    const jsrJsonRelPath = relativePosix(jsrJsonDir, jsrJsonPath);
+
+    if (!isSilent) {
+      log.info(`Reading jsr.json from ./${jsrJsonRelPath}`);
+    }
+
+    // Copy exports from zshy config to jsr.json exports
+    const jsrExports = config.exports;
+    jsrJson.exports = jsrExports;
+    if (isVerbose) {
+      log.info(`Setting "exports": ${formatForLog(jsrExports)}`);
+    }
+
+    // Write jsr json
+    if (isDryRun) {
+      log.info("[dryrun] Skipping jsr.json modification");
+    } else {
+      fs.writeFileSync(jsrJsonPath, JSON.stringify(jsrJson, null, jsrJsonIndent) + "\n");
     }
   }
 

src/utils.ts

@@ -1,3 +1,4 @@
+import * as fs from "node:fs";
 import * as path from "node:path";
 import * as ts from "typescript";
 
@@ -132,3 +133,37 @@ export function isTestFile(filePath: string): boolean {
 
   return false;
 }
+
+export function findConfigPath(fileName: string): string {
+  let resultPath = `./${fileName}`;
+  let currentDir = process.cwd();
+
+  while (currentDir !== path.dirname(currentDir)) {
+    const candidatePath = path.join(currentDir, fileName);
+    if (fs.existsSync(candidatePath)) {
+      resultPath = candidatePath;
+      break;
+    }
+    currentDir = path.dirname(currentDir);
+  }
+
+  if (!fs.existsSync(resultPath)) {
+    log.error(`❌ ${fileName} not found in current directory or any parent directories`);
+    process.exit(1);
+  }
+
+  return resultPath;
+}
+
+export function detectConfigIndention(fileContents: string): string | number {
+  let indent: string | number = 2; // Default to 2 spaces
+  const indentMatch = fileContents.match(/^([ \t]+)/m);
+
+  if (indentMatch?.[1]) {
+    indent = indentMatch[1];
+  } else if (!fileContents.includes("\n")) {
+    indent = 0; // minified
+  }
+
+  return indent;
+}

test/__snapshots__/zshy.test.ts.snap

@@ -1,5 +1,109 @@
 // Vitest Snapshot v1, https://vitest.dev/guide/snapshot.html
 
+exports[`zshy with different tsconfig configurations > should copy exports to jsr.json when jsr is true 1`] = `
+{
+  "exitCode": 0,
+  "stderr": "",
+  "stdout": "╔═══════════════════════════════════════════════╗
+   ║ zshy » the bundler-free TypeScript build tool ║
+   ╚═══════════════════════════════════════════════╝
+»  Starting build...
+»  Verbose mode enabled
+»  Detected package manager: <pm>
+»  Build will fail only on errors (default)
+»  Detected project root: <root>/test/jsr
+»  Reading package.json from ./package.json
+»  Parsed zshy config: {
+     "exports": {
+       ".": "./src/index.ts"
+     },
+     "jsr": true
+   }
+»  Reading tsconfig from ./tsconfig.json
+»  Determining entrypoints...
+   ╔══════════╤════════════════╗
+   ║ Subpath  │ Entrypoint     ║
+   ╟──────────┼────────────────╢
+   ║ "my-pkg" │ ./src/index.ts ║
+   ╚══════════╧════════════════╝
+»  Resolved build paths:
+   ╔══════════╤═══════════════╗
+   ║ Location │ Resolved path ║
+   ╟──────────┼───────────────╢
+   ║ rootDir  │ ./src         ║
+   ║ outDir   │ ./dist        ║
+   ╚══════════╧═══════════════╝
+»  Package is an ES module (package.json#/type is "module")
+»  Cleaning up outDir...
+»  Cleaning up declarationDir...
+»  Resolved entrypoints: [
+     "./src/index.ts"
+   ]
+»  Resolved compilerOptions: {
+     "lib": [
+       "lib.esnext.d.ts"
+     ],
+     "target": "ES2020",
+     "module": "ESNext",
+     "moduleResolution": "Bundler",
+     "moduleDetection": 2,
+     "allowJs": true,
+     "declaration": true,
+     "jsx": 4,
+     "allowImportingTsExtensions": true,
+     "rewriteRelativeImportExtensions": true,
+     "verbatimModuleSyntax": false,
+     "noEmit": false,
+     "strict": true,
+     "skipLibCheck": true,
+     "noFallthroughCasesInSwitch": true,
+     "noUncheckedIndexedAccess": true,
+     "esModuleInterop": true,
+     "forceConsistentCasingInFileNames": true,
+     "noUnusedLocals": true,
+     "noUnusedParameters": false,
+     "noPropertyAccessFromIndexSignature": false,
+     "sourceMap": true,
+     "declarationMap": true,
+     "resolveJsonModule": true,
+     "noImplicitOverride": true,
+     "noImplicitThis": true,
+     "outDir": "<root>/test/jsr/dist",
+     "emitDeclarationOnly": false,
+     "composite": false
+   }
+»  Building CJS... (rewriting .ts -> .cjs/.d.cts)
+»  Enabling CJS interop transform...
+»  Building ESM...
+»  Writing files (8 total)...
+     ./dist/index.cjs
+     ./dist/index.cjs.map
+     ./dist/index.d.cts
+     ./dist/index.d.cts.map
+     ./dist/index.d.ts
+     ./dist/index.d.ts.map
+     ./dist/index.js
+     ./dist/index.js.map
+»  Updating package.json...
+»  Setting "main": "./dist/index.cjs"
+»  Setting "module": "./dist/index.js"
+»  Setting "types": "./dist/index.d.cts"
+»  Setting "exports": {
+     ".": {
+       "types": "./dist/index.d.cts",
+       "import": "./dist/index.js",
+       "require": "./dist/index.cjs"
+     }
+   }
+»  Updating jsr.json...
+»  Reading jsr.json from ./jsr.json
+»  Setting "exports": {
+     ".": "./src/index.ts"
+   }
+»  Build complete!",
+}
+`;
+
 exports[`zshy with different tsconfig configurations > should not edit package.json when noEdit is true 1`] = `
 {
   "exitCode": 0,

test/jsr/dist/index.cjs

@@ -0,0 +1,10 @@
+"use strict";
+Object.defineProperty(exports, "__esModule", { value: true });
+exports.hi = hi;
+/**
+ * Main entry point for the test library
+ */
+function hi() {
+    console.log("hi");
+}
+//# sourceMappingURL=index.js.map

test/jsr/dist/index.d.cts

@@ -0,0 +1,5 @@
+/**
+ * Main entry point for the test library
+ */
+export declare function hi(): void;
+//# sourceMappingURL=index.d.ts.map

test/jsr/dist/index.d.ts

@@ -0,0 +1,5 @@
+/**
+ * Main entry point for the test library
+ */
+export declare function hi(): void;
+//# sourceMappingURL=index.d.ts.map

test/jsr/jsr.json

@@ -0,0 +1,8 @@
+{
+	"$schema": "https://jsr.io/schema/config-file.v1.json",
+	"name": "@jsr/my-pkg",
+	"version": "1.0.0",
+	"exports": {
+		".": "./src/index.ts"
+	}
+}