feat!: named exports instead of default exports

It also removes the `Codec` class and exports a plain object
instead. This has consequences for imports.

BREAKING CHANGE:

Only use names exports as default exports don't play well with
CommonJS + Typescript typing.

This means that when you use ESM imports, e.g. the raw codec is
no longer imported as

```js
import raw from 'multiformats/codecs/raw'
```

but as

```js
import * as raw from 'multiformats/codecs/raw'
```

The CJS import for codecs don't change, it's still `const raw = require('multiformats/codecs/raw`.

Though other imports change, so

```js
import CID from 'multiformats/cid'
const CID = require('multiformats/cid')
```

is now

```js
import { CID } from 'multiformats/cid'
const { CID } = require ('multiformats/cid')
```

Author: vmx

README.md

@@ -9,8 +9,8 @@ Library provides implementations for most basics and many others can be found in
 ## Interfaces
 
 ```js
-import CID from 'multiformats/cid'
-import json from 'multiformats/codecs/json'
+import { CID } from 'multiformats/cid'
+import * as json from 'multiformats/codecs/json'
 import { sha256 } from 'multiformats/hashes/sha2'
 
 const bytes = json.encode({ hello: 'world' })

src/basics.js

@@ -4,8 +4,8 @@ import * as base32 from './bases/base32.js'
 import * as base58 from './bases/base58.js'
 import * as sha2 from './hashes/sha2.js'
 
-import raw from './codecs/raw.js'
-import json from './codecs/json.js'
+import * as raw from './codecs/raw.js'
+import * as json from './codecs/json.js'
 
 import { CID, hasher, digest, varint, bytes } from './index.js'
 

src/cid.js

@@ -18,7 +18,7 @@ import { coerce } from './bytes.js'
  * @typedef {import('./bases/interface').MultibaseDecoder<Prefix>} MultibaseDecoder
  */
 
-export default class CID {
+export class CID {
   /**
    * @param {0|1} version
    * @param {number} code

src/codecs/codec.js

@@ -11,8 +11,12 @@
  * @param {(data:T) => Uint8Array} options.encode
  * @param {(bytes:Uint8Array) => T} options.decode
  */
-export const codec = ({ name, code, decode, encode }) =>
-  new Codec(name, code, encode, decode)
+export const codec = ({ name, code, decode, encode }) => {
+  const decoder = new Decoder(name, code, decode)
+  const encoder = new Encoder(name, code, encode)
+
+  return { name, code, decode, encode, decoder, encoder }
+}
 
 /**
  * @template {number} Code
@@ -64,45 +68,3 @@ export class Decoder {
     this.decode = decode
   }
 }
-
-/**
- * @template {number} Code
- * @template T
- * @typedef {import('./interface').BlockCodec<Code, T>} BlockCodec
- */
-
-/**
- * @class
- * @template {string} Name
- * @template {number} Code
- * @template T
- * @implements {BlockCodec<Code, T>}
- */
-export class Codec {
-  /**
-   * @param {Name} name
-   * @param {Code} code
-   * @param {(data:T) => Uint8Array} encode
-   * @param {(bytes:Uint8Array) => T} decode
-   */
-  constructor (name, code, encode, decode) {
-    this.name = name
-    this.code = code
-    this.encode = encode
-    this.decode = decode
-  }
-
-  get decoder () {
-    const { name, code, decode } = this
-    const decoder = new Decoder(name, code, decode)
-    Object.defineProperty(this, 'decoder', { value: decoder })
-    return decoder
-  }
-
-  get encoder () {
-    const { name, code, encode } = this
-    const encoder = new Encoder(name, code, encode)
-    Object.defineProperty(this, 'encoder', { value: encoder })
-    return encoder
-  }
-}

src/codecs/json.js

@@ -2,7 +2,7 @@
 
 import { codec } from './codec.js'
 
-export default codec({
+export const { name, code, decode, encode, decoder, encoder } = codec({
   name: 'json',
   code: 0x0200,
   encode: json => new TextEncoder().encode(JSON.stringify(json)),

src/codecs/raw.js

@@ -7,11 +7,11 @@ import { codec } from './codec.js'
  * @param {Uint8Array} bytes
  * @returns {Uint8Array}
  */
-const raw = (bytes) => coerce(bytes)
+const rawEncodeDecode = (bytes) => coerce(bytes)
 
-export default codec({
+export const { name, code, decode, encode, decoder, encoder } = codec({
   name: 'raw',
   code: 85,
-  decode: raw,
-  encode: raw
+  decode: rawEncodeDecode,
+  encode: rawEncodeDecode
 })

src/hashes/identity.js

@@ -3,7 +3,7 @@
 import { from } from './hasher.js'
 import { coerce } from '../bytes.js'
 
-export default from({
+export const identity = from({
   name: 'identity',
   code: 0x0,
   encode: (input) => coerce(input)

src/index.js

@@ -1,4 +1,4 @@
-import CID from './cid.js'
+import { CID } from './cid.js'
 import * as varint from './varint.js'
 import * as bytes from './bytes.js'
 import * as hasher from './hashes/hasher.js'

src/legacy.js

@@ -1,7 +1,7 @@
 import OldCID from 'cids'
 import * as bytes from './bytes.js'
 import { Buffer } from 'buffer'
-import CID from './cid.js'
+import { CID } from './cid.js'
 
 /**
  * @template {number} Code
@@ -11,7 +11,7 @@ import CID from './cid.js'
  * @param {Object<string, MultihashHasher>} options.hashes
  */
 
-const legacy = (codec, { hashes }) => {
+export const legacy = (codec, { hashes }) => {
   /**
    * @param {*} obj
    */
@@ -139,7 +139,6 @@ const legacy = (codec, { hashes }) => {
   return { defaultHashAlg, codec: codec.code, util, resolver }
 }
 
-export default legacy
 /**
  * @typedef {import('./hashes/interface').MultihashHasher} MultihashHasher
  */

test/test-block.js

@@ -1,5 +1,5 @@
 /* globals describe, it */
-import codec from 'multiformats/codecs/json'
+import * as codec from 'multiformats/codecs/json'
 import { sha256 as hasher } from 'multiformats/hashes/sha2'
 import * as main from 'multiformats/block'
 import { CID, bytes } from 'multiformats'

test/test-legacy.js

@@ -1,12 +1,12 @@
 /* globals before, describe, it */
 import { Buffer } from 'buffer'
 import assert from 'assert'
-import legacy from 'multiformats/legacy'
-import rawCodec from 'multiformats/codecs/raw'
-import jsonCodec from 'multiformats/codecs/json'
+import { legacy } from 'multiformats/legacy'
+import * as rawCodec from 'multiformats/codecs/raw'
+import * as jsonCodec from 'multiformats/codecs/json'
 import { sha256, sha512 } from 'multiformats/hashes/sha2'
 import { codec } from 'multiformats/codecs/codec'
-import CID from 'multiformats/cid'
+import { CID } from 'multiformats/cid'
 
 const same = assert.deepStrictEqual
 const test = it

test/test-multicodec.js

@@ -1,8 +1,8 @@
 /* globals describe, it */
 import * as bytes from '../src/bytes.js'
 import assert from 'assert'
-import raw from 'multiformats/codecs/raw'
-import json from 'multiformats/codecs/json'
+import * as raw from 'multiformats/codecs/raw'
+import * as json from 'multiformats/codecs/json'
 import { codec } from 'multiformats/codecs/codec'
 const same = assert.deepStrictEqual
 const test = it

test/test-multihash.js

@@ -5,7 +5,7 @@ import valid from './fixtures/valid-multihash.js'
 import invalid from './fixtures/invalid-multihash.js'
 import crypto from 'crypto'
 import { sha256, sha512, __browser } from 'multiformats/hashes/sha2'
-import identity from 'multiformats/hashes/identity'
+import { identity } from 'multiformats/hashes/identity'
 import { decode as decodeDigest, create as createDigest } from 'multiformats/hashes/digest'
 const test = it
 const encode = name => data => coerce(crypto.createHash(name).update(data).digest())

test/ts-use/src/main.ts

@@ -1,6 +1,6 @@
 import * as Block from 'multiformats/block'
 import { sha256 } from 'multiformats/hashes/sha2'
-import json from 'multiformats/codecs/json'
+import * as json from 'multiformats/codecs/json'
 
 const main = async () => {
   const block = await Block.encode({