emit-error

emit-error

Emit error if callback is executed with a truthy 1st argument

example

var EventEmitter = require('events').EventEmitter,
    emitError    = require('emit-error')

var emitter = new EventEmitter().on('error', function (err) {
    console.error(err)
})

function fail (cb) {
    cb(new Error('failed'))
}

function succeed (cb) {
    cb(null, 'success')
}

fail(emitError(emitter, function (status) {
    console.log('will not see this')
}))

fail(emitError(emitter, {alwaysCall: true}, function (err, status) {
    // When always call specified, err is passed
    console.log('will see this')
}))

succeed(emitError(emitter, function (status) {
    // Gets called with status of success
    console.log(status)
}))

api

emitError

var emitError = require('emit-error')

var wrappedCb = emitError(emitter [, options, cb])

Returns a function that when called with a truthy first argument, will emit that value as an error event on the supplied event emitter. If the option alwaysCall is defined, the provided cb will be executed in all cases with all arguments supplied to wrappedCb, otherwise if the 1st argument to wrappedCb is falsey, the supplied cb will be executed with all but the 1st argument supplied to wrappedCb.

If no callback cb is provided, then the generated callback will simply emit error events when called with a non-falsey 1st argument.

options:

• alwaysCall: true or false - if true, the provided callback cb will always be called (and include the 1st argument), otherwise it will only be called when a the first argument is falsey (and without the 1st argument)

testing

npm test [--dot | --spec] [--coverage]

options

• --dot - output test results as dots instead of tap
• --spec - output test results as spec instead of tap
• --coverage - display text cover report
• --testling - run tests in browser via testling (cannot be used with --coverage and expects both browserify and testling to be installed globally)

patterns

Only run test files matching a certain pattern by prefixing the test command with grep=pattern. Example:

grep=connect npm test --dot

html coverage report

Open it with npm run view-cover or npm run vc