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3.0.0 • Public • Published


Generate trash JavaScript. This is useful for testing libraries and APIs.

The strings that are generated are random, but every string comes from a single Unicode script, so they at least look vaguely interesting.


npm install basura

Command line

Usage: basura [options]

Generate a random JavaScript object

  -V, --version                output the version number
  -a, --arrayLength <number>   Maximum array/object size (default: 10)
  -b, --noBoxed                Do not generate boxed types, like String.
  -c, --cborSafe               Do not generate types that break CBOR.
  -d, --depth <number>         Maximum depth. (default: 5)
  -e, --edgeFreq <number>      Edge case frequency. (default: 0.1)
  -i, --import <file>          Import the given file, and use its default
                               export as an additional type generator.  Can be
                               specified multiple times. (default: [])
  -j, --json                   Output JSON, not generating any types that will
                               not fit.
  -o, --output <file>          File to output.
  -s, --stringLength <number>  Maximum string length. (default: 20)
  -t, --type <type>            Generate this specific type.
  -T, --listTypes              List all supported types, then exit.
  -h, --help                   display help for command

  $ basura -t object
  $ basura -t Array -o array.js

Supported Types

  • AggregateError
  • Array
  • ArrayBuffer
  • BigInt64Array
  • BigUint64Array
  • Boolean
  • Buffer
  • DataView
  • Date
  • Error
  • EvalError
  • Float32Array
  • Float64Array
  • Generator
  • Int16Array
  • Int32Array
  • Int8Array
  • Map
  • Number
  • Object
  • Promise
  • Proxy
  • RangeError
  • ReferenceError
  • RegExp
  • Set
  • SharedArrayBuffer
  • String
  • SyntaxError
  • TypeError
  • URIError
  • URL
  • Uint16Array
  • Uint32Array
  • Uint8Array
  • Uint8ClampedArray
  • WeakMap
  • WeakRef
  • WeakSet
  • bigint
  • boolean
  • function
  • integer
  • number
  • string
  • symbol
  • undefined

Adding new types

Pass new types in the types option, or from the command line, use --import <moduleFile>. See an example.


Full API docs are available.

import {Basura} from 'basura'

// The default options.  No need to pass anything in if you like these
const opts = {
  arrayLength: 10,  // maximum size of arrays and objects
  cborSafe: false,  // generate only CBOR-safe types?
  depth: 5,         // How deep to go
  edgeFreq: 0.1,    // How often to prefer edge cases?
  jsonSafe: false,  // generate only JSON-safe types?
  noBoxed: false,   // ignore boxed types, like String?
  output: false,    // add custom inspect functions that make output parseable JS?
  scripts: [],      // Array of script names to limit output to.  Defaults to all
  stringLength: 20, // Maximum string and Buffer length, in codepoints
  types: {},        // Extra types to generate.  Pass in `{Date: null}` to not generate Dates
const b = new Basura(opts)
console.log(b.generate_Date()) // Example output: 2011-02-16T11:28:41.539Z
console.log(b.generate()) // Some possibly-large chunk of JS

See some example output in the examples directory.

Tests Coverage Status

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