build: setup library building task

Author: shine1594

.eslintignore

@@ -1 +1,3 @@
-node_modules
+node_modules
+dist
+lib

.gitignore

@@ -1,4 +1,5 @@
-node_modules
 .idea
 .DS_Store
 .vscode
+node_modules/
+dist/

.prettierignore

@@ -1 +1,3 @@
-node_modules
+node_modules
+dist
+lib

babel.config.cjs

@@ -0,0 +1,33 @@
+module.exports = (api) => {
+  api.cache(true);
+  const targets = { ie: 11 };
+
+  const plugins = [
+    [
+      "@babel/plugin-transform-runtime",
+      {
+        corejs: 3,
+      },
+    ],
+  ];
+
+  return {
+    presets: [
+      [
+        "@babel/preset-typescript",
+        {
+          onlyRemoveTypeImports: true,
+        },
+      ],
+      [
+        "@babel/preset-env",
+        {
+          targets,
+        },
+      ],
+    ],
+    plugins,
+    comments: false,
+    sourceMaps: true,
+  };
+};

build/Awaited4-2.ts

@@ -0,0 +1,9 @@
+type Awaited<T> = T extends null | undefined
+  ? T // special case for `null | undefined` when not in `--strictNullChecks` mode
+  : T extends object & { then(onfulfilled: infer F): any } // `await` only unwraps object types with a callable `then`. Non-object types are not unwrapped
+  ? F extends (value: infer V) => any // if the argument to `then` is callable, extracts the argument
+    ? Awaited<V> // recursively unwrap the value
+    : never // the argument to `then` was not callable
+  : T; // non-object or non-thenable
+
+export default Awaited;

build/compile-types.sh

@@ -0,0 +1,12 @@
+#!/bin/sh
+mv ./src/types/Awaited.ts ./build/Awaited4-5.ts
+mv ./build/Awaited4-2.ts ./src/types/Awaited.ts
+
+npm i [email protected] -D --legacy-peer-deps
+npm run compile:types4-2
+
+mv ./src/types/Awaited.ts ./build/Awaited4-2.ts
+mv ./build/Awaited4-5.ts ./src/types/Awaited.ts
+
+npm i typescript@beta -D --legacy-peer-deps
+npm run compile:types4-5

build/generateExports.ts

@@ -0,0 +1,100 @@
+import glob from "glob";
+import { readFile, writeFile } from "fs/promises";
+import { drop, map, not, pipe, reduce } from "../src/index";
+
+const SOURCE_DIR = "./src";
+const OUTPUT_DIR = "./dist";
+const CJS_ROOT_DIR = `${OUTPUT_DIR}/cjs`;
+const ESM_ROOT_DIR = `${OUTPUT_DIR}/esm`;
+const ESM5_ROOT_DIR = `${OUTPUT_DIR}/esm5`;
+
+const conditionalRootIndex = {
+  import: `${ESM_ROOT_DIR}/index.js`,
+  require: `${CJS_ROOT_DIR}/index.js`,
+};
+
+const conditionalRootIndexLazy = {
+  import: `${ESM_ROOT_DIR}/Lazy/index.js`,
+  require: `${CJS_ROOT_DIR}/Lazy/index.js`,
+};
+
+const defaultSubPathExports = {
+  "./package.json": "./package.json",
+  ".": conditionalRootIndex,
+  "./index": conditionalRootIndex,
+  "./index.js": conditionalRootIndex,
+  "./Lazy": conditionalRootIndexLazy,
+  "./Lazy/index": conditionalRootIndexLazy,
+  "./Lazy/index.js": conditionalRootIndexLazy,
+  "./esm5": `${ESM5_ROOT_DIR}/index.js`,
+  "./esm5/index": `${ESM5_ROOT_DIR}/index.js`,
+  "./esm5/index.js": `${ESM5_ROOT_DIR}/index.js`,
+  "./esm5/Lazy": `${ESM5_ROOT_DIR}/Lazy/index.js`,
+  "./esm5/Lazy/index": `${ESM5_ROOT_DIR}/Lazy/index.js`,
+  "./esm5/Lazy/index.js": `${ESM5_ROOT_DIR}/Lazy/index.js`,
+};
+
+const searchFiles = (pattern: string): Promise<string[]> =>
+  new Promise((resolve, reject) => {
+    glob(pattern, function (err, files) {
+      if (err) reject(err);
+      else resolve(files);
+    });
+  });
+
+async function generateExports() {
+  const fileNames = await Promise.all([
+    searchFiles(`${SOURCE_DIR}/*.ts`),
+    searchFiles(`${SOURCE_DIR}/_internal/*.ts`),
+    searchFiles(`${SOURCE_DIR}/Lazy/*.ts`),
+  ]).then((lists) =>
+    lists
+      .flat()
+      .filter((a) => not(a.endsWith("index.ts")))
+      .map((fileName) =>
+        [...drop(2, fileName.split("/"))].join("/").replace(".ts", ""),
+      ),
+  );
+
+  const subPathExports = pipe(
+    fileNames,
+    map((name) => {
+      const conditionalSubPaths = {
+        import: `${ESM_ROOT_DIR}/${name}.js`,
+        require: `${CJS_ROOT_DIR}/${name}.js`,
+      };
+      return {
+        [`./${name}`]: conditionalSubPaths,
+        [`./${name}.js`]: conditionalSubPaths,
+        [`./esm5/${name}`]: `${ESM5_ROOT_DIR}/${name}.js`,
+        [`./esm5/${name}.js`]: `${ESM5_ROOT_DIR}/${name}.js`,
+      };
+    }),
+    (iter) => reduce((acc, field) => Object.assign(acc, field), {}, iter),
+  );
+
+  const packageJsonObject = JSON.parse(
+    String(await readFile("./package.json")),
+  );
+
+  await writeFile(
+    "./package.json",
+    JSON.stringify(
+      Object.assign(packageJsonObject, {
+        exports: {
+          ...defaultSubPathExports,
+          ...subPathExports,
+        },
+      }),
+    ),
+  );
+}
+
+(async function main() {
+  await Promise.all([
+    // Add package.json file to cjs directory
+    writeFile(`${CJS_ROOT_DIR}/package.json`, '{ "type": "commonjs" }'),
+    // Generate and add 'exports' field to root package.json
+    generateExports(),
+  ]);
+})();