Initial import with skill sheet working

node_modules/level-transcoder/lib/formats.js

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+'use strict'
+
+const { Buffer } = require('buffer') || {}
+const { Encoding } = require('./encoding')
+const textEndec = require('./text-endec')
+
+/**
+ * @template TIn, TOut
+ * @extends {Encoding<TIn,Buffer,TOut>}
+ */
+class BufferFormat extends Encoding {
+  /**
+   * @param {Omit<IEncoding<TIn, Buffer, TOut>, 'format'>} options
+   */
+  constructor (options) {
+    super({ ...options, format: 'buffer' })
+  }
+
+  /** @override */
+  createViewTranscoder () {
+    return new ViewFormat({
+      encode: this.encode, // Buffer is a view (UInt8Array)
+      decode: (data) => this.decode(
+        Buffer.from(data.buffer, data.byteOffset, data.byteLength)
+      ),
+      name: `${this.name}+view`
+    })
+  }
+
+  /** @override */
+  createBufferTranscoder () {
+    return this
+  }
+}
+
+/**
+ * @extends {Encoding<TIn,Uint8Array,TOut>}
+ * @template TIn, TOut
+ */
+class ViewFormat extends Encoding {
+  /**
+   * @param {Omit<IEncoding<TIn, Uint8Array, TOut>, 'format'>} options
+   */
+  constructor (options) {
+    super({ ...options, format: 'view' })
+  }
+
+  /** @override */
+  createBufferTranscoder () {
+    return new BufferFormat({
+      encode: (data) => {
+        const view = this.encode(data)
+        return Buffer.from(view.buffer, view.byteOffset, view.byteLength)
+      },
+      decode: this.decode, // Buffer is a view (UInt8Array)
+      name: `${this.name}+buffer`
+    })
+  }
+
+  /** @override */
+  createViewTranscoder () {
+    return this
+  }
+}
+
+/**
+ * @extends {Encoding<TIn,string,TOut>}
+ * @template TIn, TOut
+ */
+class UTF8Format extends Encoding {
+  /**
+   * @param {Omit<IEncoding<TIn, string, TOut>, 'format'>} options
+   */
+  constructor (options) {
+    super({ ...options, format: 'utf8' })
+  }
+
+  /** @override */
+  createBufferTranscoder () {
+    return new BufferFormat({
+      encode: (data) => Buffer.from(this.encode(data), 'utf8'),
+      decode: (data) => this.decode(data.toString('utf8')),
+      name: `${this.name}+buffer`
+    })
+  }
+
+  /** @override */
+  createViewTranscoder () {
+    const { textEncoder, textDecoder } = textEndec()
+
+    return new ViewFormat({
+      encode: (data) => textEncoder.encode(this.encode(data)),
+      decode: (data) => this.decode(textDecoder.decode(data)),
+      name: `${this.name}+view`
+    })
+  }
+
+  /** @override */
+  createUTF8Transcoder () {
+    return this
+  }
+}
+
+exports.BufferFormat = BufferFormat
+exports.ViewFormat = ViewFormat
+exports.UTF8Format = UTF8Format
+
+/**
+ * @typedef {import('./encoding').IEncoding<TIn,TFormat,TOut>} IEncoding
+ * @template TIn, TFormat, TOut
+ */