assert-enhanced

✨ An enhanced Node.js assert module.

IMPORTANT: This module is an improvement from joyent/node-assert-plus module with added assertions registration methods.

Installation:

npm install assert-enhanced

For types definitions:

npm install AshLePoney/node-assert-enhanced-types --save-dev

Example:

const assert = require('assert-enhanced');

function example (stdout, chunk, next) {
  assert.writable(stdout, 'stdout');
  assert.object(chunk, 'chunk');
  assert.string(chunk.id, 'chunk.id');
  assert.buffer(chunk.buffer, 'chunk.buffer');
  assert.func(next, 'next');

  // ...

  stdout.write(chunk);
}

Or to add a new assertion set

const assert = require('assert-enhanced');

const definition = {
  custom: {
    check: (arg) => (arg instanceof Custom),
    operator: 'instanceof',
    actual: (arg) => Object.prototype.toString.call(arg).slice(8, -1)
  }
};

assert.register(null, definitions, { arrayOf: false, optionalArrayOf: false });

// Register to assert-enhanced:
// assert.custom
// assert.optionalCustom
// assert.arrayOfCustom         (generation disabled by options).
// assert.optionalArrayOfCustom (generation disabled by options).

API:

The added assertions methods take two arguments, the value tested first and then the name of the checked parameter.

assert.bool(myBoolArg, 'myBoolArg');
assert.optionalBool(myBoolArg, 'myBoolArg');
assert.arrayOfbool(myBoolArg, 'myBoolArg');
assert.optionalArrayOfBool(myBoolArg, 'myBoolArg');

On bad assertion it will throw an EnhancedAssertionError:

AssertionError [ERR_ASSERTION]: myBoolArg (bool) is required.
    at Object.<anonymous> (/home/user/projects/test-assert-enhanced/test.js:3:8)
    at Module._compile (internal/modules/cjs/loader.js:1147:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:1167:10)
    at Module.load (internal/modules/cjs/loader.js:996:32)
    at Function.Module._load (internal/modules/cjs/loader.js:896:14)
    at Function.executeUserEntryPoint [as runMain] (internal/modules/run_main.js:71:12)
    at internal/main/run_main_module.js:17:47

Enhanced:

• assert.EnhancedAssertionError
• assert.bool
• assert.number
• assert.string
• assert.symbol
• assert.object
• assert.func
• assert.array
• assert.asyncFunc
• assert.promise
• assert.date
• assert.regexp
• assert.buffer
• assert.stream
• assert.readable
• assert.writable
• assert.duplex
• assert.optionalBool
• assert.optionalNumber
• assert.optionalString
• assert.optionalSymbol
• assert.optionalObject
• assert.optionalFunc
• assert.optionalArray
• assert.optionalAsyncFunction
• assert.optionalPromise
• assert.optionalDate
• assert.optionalRegexp
• assert.optionalBuffer
• assert.optionalStream
• assert.optionalReadable
• assert.optionalWritable
• assert.optionalDuplex
• assert.arrayOfBool
• assert.arrayOfNumber
• assert.arrayOfString
• assert.arrayOfSymbol
• assert.arrayOfObject
• assert.arrayOfFunc
• assert.arrayOfArray
• assert.arrayOfAsyncFunc
• assert.arrayOfPromise
• assert.arrayOfDate
• assert.arrayOfRegexp
• assert.arrayOfBuffer
• assert.arrayOfStream
• assert.arrayOfReadable
• assert.arrayOfWritable
• assert.arrayOfDuplex
• assert.optionalArrayOfBool
• assert.optionalArrayOfNumber
• assert.optionalArrayOfString
• assert.optionalArrayOfSymbol
• assert.optionalArrayOfObject
• assert.optionalArrayOfFunc
• assert.optionalArrayOfArray
• assert.optionalArrayOfAsyncFunc
• assert.optionalArrayOfPromise
• assert.optionalArrayOfDate
• assert.optionalArrayOfRegexp
• assert.optionalArrayOfBuffer
• assert.optionalArrayOfStream
• assert.optionalArrayOfReadable
• assert.optionalArrayOfWritable
• assert.optionalArrayOfDuplex

Enhanced registration methods:

• assert.register
• assert.registerStandardAssertion
• assert.registerOptionalAssertion
• assert.registerArrayOfAssertion
• assert.registerOptionalArrayOfAssertion
• assert.getClassname
• assert.getTypeof

Node.js assert module:

See more on Node.js assert module: https://nodejs.org/api/assert.html

• assert
• assert.AssertionError
• assert.fail
• assert.ok
• assert.equal (deprecated)
• assert.notEqual (deprecated)
• assert.deepEqual (deprecated)
• assert.notDeepEqual (deprecated)
• assert.strictEqual
• assert.notStrictEqual
• assert.deepStrictEqual
• assert.notDeepStrictEqual
• assert.ifError
• assert.throws (>= v10.0.0)
• assert.rejects (>= v10.0.0)
• assert.doesNotThrow (>= v10.0.0)
• assert.doesNotReject (>= v10.0.0)
• assert.match (>= v13.6.0)
• assert.doesNotMatch (>= v13.6.0)

assert.register(target, definitions, options)->target

Register assertions sets.

argument	type	details
target	Object or Function	The target where to save the generated assertion methods. If it's null or undefined then registration is processed on the exported module.
definitions	Object	The definitions object will wrap the definitions of the different assertions that need to be added.
options	Object (optional)	The options object will store the states to know if we should cancel the generation of methods by types. Any registration type can be disabled using options ({ [type]: false }).

Example:

const definitions = {
  custom: {
    check: (arg) => (arg instanceof Custom),
    operator: 'instanceof',
    actual: assert.getClassname
  }
};

assert.register(null, definitions, { optionalArrayOf: false });

// Register [standard, optional, arrayOf]

assert.registerStandardAssertion(target, name, definition)->target

Register standard assertion.

argument	type	details
target	Object or Function	The target where to save the generated assertion methods. If it's null or undefined then registration is processed on the exported module.
name	String	The assertion method name.
definition	Object	The definitions object.

Example:

assert.registerStandardAssert(null, 'custom', {
  check: (arg) => (arg instanceof Custom),
  operator: 'instanceof',
  actual: assert.getClassname
});

assert.registerOptionalAssertion(target, name, definition)->target

Register optional assertion.

argument	type	details
target	Object or Function	The target where to save the generated assertion methods. If it's null or undefined then registration is processed on the exported module.
name	String	The assertion method name.
definition	Object	The definitions object.

Example:

assert.registerOptionalAssertion(null, 'custom', {
  check: (arg) => (arg instanceof Custom),
  operator: 'instanceof',
  actual: assert.getClassname
});

assert.registerArrayOfAssertion(target, name, definition)->target

Register arrayOf assertion.

argument	type	details
target	Object or Function	The target where to save the generated assertion methods. If it's null or undefined then registration is processed on the exported module.
name	String	The assertion method name.
definition	Object	The definitions object.

Example:

assert.registerArrayOfAssertion(null, 'custom', {
  check: (arg) => (arg instanceof Custom),
  operator: 'instanceof',
  actual: assert.getClassname
});

assert.registerOptionalArrayOfAssertion(target, name, definition)->target

Register optional arrayOf assertion.

argument	type	details
target	Object or Function	The target where to save the generated assertion methods. If it's null or undefined then registration is processed on the exported module.
name	String	The assertion method name.
definition	Object	The definitions object.

Example:

assert.registerOptionalArrayOfAssertion(null, 'custom', {
  check: (arg) => (arg instanceof Custom),
  operator: 'instanceof',
  actual: assert.getClassname
});

assert.getClassname(arg)->string

Get an object classname, it's used to seed the actual property from the definitions.

argument	type	details
arg	any

assert.getTypeof(arg)->string

Get a typeof, it's used to seed the actual property from the definitions.

argument	type	details
arg	any