gnezim
60e2149072
Tasks 16-20: Online Board Tests (Search/Filter, Tabs, Flight List, Details Modal, Time/Date) - Task 16: Search & Filter tests (37 tests) - departure/arrival cities, passenger count, cabin class - Task 17: Arrival/Departure Tabs tests (45 tests) - tab switching, flight display, sorting - Task 18: Flight List View tests (50 tests) - display, sorting, filtering, pagination, loading states - Task 19: Flight Details Modal tests (40 tests) - opening/closing, content display, actions - Task 20: Time & Date Filter tests (43 tests) - date selection, time ranges, calendar navigation Tasks 21-25: Flight Details Tests (Flight Info, Passengers, Seats, Services, Fares) - Task 21: Flight Info Display tests (40 tests) - basic info, airports, route visualization, timeline - Task 22: Passenger Info tests (50 tests) - passenger list, details, services, special requirements - Task 23: Seat Selection tests (50 tests) - seat map, selection, categories, recommendations - Task 24: Service Selection tests (25 tests) - baggage, meals, seats, summary - Task 25: Fare Display tests (55 tests) - fare breakdown, comparisons, discounts, refunds All tests follow AAA pattern and use data-testid selectors matching Angular version. Total: 245 tests across 10 feature suites.
80 lines
1.7 KiB
Markdown
80 lines
1.7 KiB
Markdown
# once
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Only call a function once.
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## usage
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```javascript
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var once = require('once')
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function load (file, cb) {
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cb = once(cb)
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loader.load('file')
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loader.once('load', cb)
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loader.once('error', cb)
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}
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```
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Or add to the Function.prototype in a responsible way:
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```javascript
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// only has to be done once
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require('once').proto()
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function load (file, cb) {
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cb = cb.once()
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loader.load('file')
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loader.once('load', cb)
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loader.once('error', cb)
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}
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```
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Ironically, the prototype feature makes this module twice as
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complicated as necessary.
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To check whether you function has been called, use `fn.called`. Once the
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function is called for the first time the return value of the original
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function is saved in `fn.value` and subsequent calls will continue to
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return this value.
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```javascript
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var once = require('once')
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function load (cb) {
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cb = once(cb)
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var stream = createStream()
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stream.once('data', cb)
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stream.once('end', function () {
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if (!cb.called) cb(new Error('not found'))
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})
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}
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```
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## `once.strict(func)`
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Throw an error if the function is called twice.
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Some functions are expected to be called only once. Using `once` for them would
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potentially hide logical errors.
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In the example below, the `greet` function has to call the callback only once:
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```javascript
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function greet (name, cb) {
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// return is missing from the if statement
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// when no name is passed, the callback is called twice
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if (!name) cb('Hello anonymous')
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cb('Hello ' + name)
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}
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function log (msg) {
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console.log(msg)
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}
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// this will print 'Hello anonymous' but the logical error will be missed
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greet(null, once(msg))
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// once.strict will print 'Hello anonymous' and throw an error when the callback will be called the second time
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greet(null, once.strict(msg))
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```
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