Basura

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.

Install

npm install basura

Command line

Usage: basura [options]

Generate a random JavaScript object

Options:
  -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

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

API

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
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See some example output in the examples directory.

Development

To recreate lib/data.js:

• Unzip a copy of the Unicode Database into data/ucd
• npm run data

TODO: the IDNA properties are based on Unicode 12.