feat: initial implementation

.eslintrc.json

@@ -15,6 +15,13 @@
     "project": ["./tsconfig.json"]
   },
   "ignorePatterns": ["/coverage/", "/dist/"],
+  "rules": {
+    "@typescript-eslint/naming-convention": "off",
+    "@typescript-eslint/restrict-plus-operands": "off",
+    "@typescript-eslint/no-unsafe-return": "off",
+    "functional/functional-parameters": "off",
+    "import/extensions": "off"
+  },
   "overrides": [
     {
       "files": ["**/*.test.ts"],

package.json

@@ -25,12 +25,14 @@
   "type": "module",
   "exports": {
     ".": {
+      "default": "./src/base/index.ts",
       "types": {
         "import": "./dist/index.d.mts",
         "require": "./dist/index.d.cts"
       }
     },
     "./functions": {
+      "default": "./src/functions/index.ts",
       "types": {
         "import": "./dist/functions.d.mts",
         "require": "./dist/functions.d.cts"
@@ -39,6 +41,7 @@
       "require": "./dist/functions.cjs"
     },
     "./functions/higher-order": {
+      "default": "./src/functions-ho/index.ts",
       "types": {
         "import": "./dist/functions-ho.d.mts",
         "require": "./dist/functions-ho.d.cts"
@@ -47,12 +50,14 @@
       "require": "./dist/functions-ho.cjs"
     },
     "./si-units": {
+      "default": "./src/si-units/index.ts",
       "types": {
         "import": "./dist/si-units.d.mts",
         "require": "./dist/si-units.d.cts"
       }
     },
     "./si-units/converters": {
+      "default": "./src/si-units/converters/index.ts",
       "types": {
         "import": "./dist/si-units-converters.d.mts",
         "require": "./dist/si-units-converters.d.cts"
@@ -82,7 +87,9 @@
     "lint:prettier-fix": "prettier \"**/*\" --ignore-unknown --write",
     "lint:spelling": "cspell \"**\" \".github/**/*\"",
     "prepare": "husky install",
-    "release": "semantic-release",
+    "release": "pnpm run release:pre && pnpm run release:semantic",
+    "release:pre": "node --no-warnings=ExperimentalWarning --loader=ts-paths-esm-loader/transpile-only --experimental-specifier-resolution=node ./scripts/pre-release.ts",
+    "release:semantic": "semantic-release",
     "test": "pnpm run test:js",
     "test:js": "c8 ava",
     "type-check": "tsc --noEmit"

rollup.config.ts

@@ -1,3 +1,6 @@
+import assert from "node:assert/strict";
+import path from "node:path";
+
 import rollupPluginNodeResolve from "@rollup/plugin-node-resolve";
 import rollupPluginTypescript from "@rollup/plugin-typescript";
 import { defineConfig, type Plugin } from "rollup";
@@ -6,20 +9,39 @@ import rollupPluginDts from "rollup-plugin-dts";
 
 import pkg from "./package.json" assert { type: "json" };
 
-const entries = [
-  ["src/base/index.ts", pkg.exports["."]],
-  ["src/functions/index.ts", pkg.exports["./functions"]],
-  ["src/functions-ho/index.ts", pkg.exports["./functions/higher-order"]],
-  ["src/si-units/index.ts", pkg.exports["./si-units"]],
-  ["src/si-units/converters/index.ts", pkg.exports["./si-units/converters"]],
-] as const;
-
 const common = defineConfig({
   output: {
     sourcemap: false,
   },
 
-  external: [],
+  external: (
+    source: string,
+    importer: string | undefined,
+    isResolved: boolean,
+  ) => {
+    if (!isResolved || importer === undefined) {
+      return null;
+    }
+
+    assert(path.isAbsolute(source));
+    const relativeSource = path.relative(process.cwd(), source);
+    const relativeImporter = path.relative(process.cwd(), importer);
+
+    if (!relativeSource.startsWith("src/")) {
+      return null;
+    }
+
+    const sourceSubproject = relativeSource.slice(
+      4,
+      Math.max(0, relativeSource.indexOf("/", 4)),
+    );
+    const importerSubproject = relativeImporter.slice(
+      4,
+      Math.max(0, relativeImporter.indexOf("/", 4)),
+    );
+
+    return sourceSubproject !== importerSubproject;
+  },
 
   treeshake: {
     annotations: true,
@@ -52,20 +74,20 @@ const types = defineConfig({
   ] as Plugin[],
 });
 
-export default entries
-  .flatMap(([entry, output]) => [
-    "import" in output
+export default Object.values(pkg.exports)
+  .flatMap((pkgExports) => [
+    "import" in pkgExports
       ? {
           ...runtimes,
-          input: entry,
+          input: pkgExports.default,
           output: [
             {
-              file: output.import,
+              file: pkgExports.import,
               format: "esm",
               sourcemap: false,
             },
             {
-              file: output.require,
+              file: pkgExports.require,
               format: "cjs",
               sourcemap: false,
             },
@@ -74,15 +96,15 @@ export default entries
       : null,
     {
       ...types,
-      input: entry,
+      input: pkgExports.default,
       output: [
         {
-          file: output.types.import,
+          file: pkgExports.types.import,
           format: "esm",
           sourcemap: false,
         },
         {
-          file: output.types.require,
+          file: pkgExports.types.require,
           format: "cjs",
           sourcemap: false,
         },

scripts/pre-release.ts

@@ -0,0 +1,42 @@
+import childProcess from "node:child_process";
+import fs from "node:fs/promises";
+import util from "node:util";
+
+import pkg from "../package.json" assert { type: "json" };
+
+const exec = util.promisify(childProcess.exec);
+
+if (
+  process.env["CI"] === undefined ||
+  process.env["CI"] === "" ||
+  process.env["CI"] === "0"
+) {
+  throw new Error("Not in CI Environment");
+}
+
+const releasePkg = Object.fromEntries(
+  Object.entries(pkg).map(([key, value]): [string, unknown] => {
+    if (key === "exports") {
+      return [
+        key,
+        Object.fromEntries(
+          Object.entries(value).map(
+            ([exportsKey, exportsValue]): [string, unknown] => {
+              const { default: _, ...updatedExportsValue } = exportsValue;
+              return [exportsKey, updatedExportsValue];
+            },
+          ),
+        ),
+      ];
+    }
+
+    return [key, value];
+  }),
+);
+
+await fs.writeFile("./package.json", JSON.stringify(releasePkg, undefined, 2), {
+  encoding: "utf8",
+});
+
+await exec("git add package.json");
+await exec('git commit -m "build: package.json"');

src/base/core.ts

@@ -0,0 +1,27 @@
+import { type BrandUnit } from "./utils";
+
+export type Exponent = -6 | -5 | -4 | -3 | -2 | -1 | 0 | 1 | 2 | 3 | 4 | 5 | 6;
+
+export type UnitFull<T extends Record<string, UnitValue>> = number &
+  Readonly<BrandUnit<T>>;
+
+export type UnitValue = { exponent: Exponent } & Record<string, Exponent>;
+
+/**
+ * A unit of measurement.
+ */
+export type Unit<T extends Record<string, Exponent | UnitValue>> = UnitFull<{
+  [K in keyof T]: T[K] extends Exponent
+    ? {
+        exponent: T[K];
+      }
+    : T[K] extends UnitValue
+    ? T[K]
+    : never;
+}>;
+
+export type UnknownUnit = number &
+  Readonly<{
+    __exactKeys: string;
+    __uom_types: Record<string, {}>;
+  }>;

src/base/index.ts

@@ -1,3 +1,2 @@
-/* eslint-disable unicorn/no-empty-file */
-
-// Write me
+export type { Unit, UnknownUnit } from "./core";
+export type { Multiply, Divide, Inverse } from "./utils";