We didn’t want to leave front-end developers in the dark when their Javascript throws errors, so we’ve...
Run your Jasmine specs without a browser
...execute browser-less, console-based, javascript + DOM code right from within your Rails test suite...
Johnson wraps JavaScript in a loving Ruby embrace. It embeds the Mozilla SpiderMonkey JavaScript runtime as a C extension...
Here are a few common patterns that will probably lead to flaky specs. If you notice them in your specs, please make sure that you have not introduced a flaky...
Using Capybara RSpec matchers One rule of thumb I try to follow in capybara tests is using capybara matchers and not plain rspec matchers. One example: visit(some_page...
...can use ETags to allow clients to use cached responses, if your application would send the same contents as before. Besides what "actually" defines your response's contents, your application...
...probably also considers "global" conditions, like which user is signed in: class ApplicationController < ActionController::Base etag { current_user&.id } etag { current_user&.updated_at } end Under the hood, Rails generates...
...the new way to do it, and it's great, especially in combination with Sprockets (or Propshaft on Rails 7). You might be missing some convenience features, though.
...cover one specific issue: Once you have started your development Rails server and esbuild with the --watch option (if you used jsbundling-rails to set up, you probably use bin/dev...
...record/replay cassettes for any RSpec example tagged as :vcr or vcr: true. If a spec is not tagged with :vcr, VCR will complain about any attempted HTTP request. This is...
...this off temporarily, e.g. to communicate with an actual API while writing a new spec, simply add the line c.allow_http_connections_when_no_cassette = true to the VCR.configure-block...
...Plotting graphs in Ruby with Gruff, which comes handy for many uses cases, you sometimes might need configuration for more advanced plots, e.g. for academic concerns. Then using Gnuplot, the...
...first academic open source plotting software, might be a good option. There are several wrappers for Ruby available and I mainly looked at one of the two most frequently used...
When ending a Selenium test Capybara resets the browser state by closing the tab, clearing cookies, localStorage, etc. It may be a good idea to wait for all in-flight...
...AJAX requests to finish before ending a scenario: You may have client-side JavaScript that freaks out when the tab closure kills their pending requests. If that JavaScript opens an...
expect(page).to have_field('Username') { |field| field[:class].blank? } Limitations Using execute_script, evaluate_script or evaluate_async_script within a filter block will crash with a timeout...
...Selenium::WebDriver::Error::ScriptTimeoutError Exception: script timeout This is due to Capybara using a zero timeout while calling the filter block. A workaround is to temporarily set a different timeout...
...build) on a relation, the newly created record inherits values from the relation’s scoped attributes: # User(id: integer, name: string) user = User.where(name: "hello").create user.name # => "hello"
...works if the scope condition is a hash with scalar values, that materialize as equality comparisons. If your scope uses an SQL snippet, or any operator other than equality, the...
GoodJob and ActiveJob rescue exceptions internally, preventing exception_notification from triggering. This can cause silent job failures.To get notified, subscribe to ActiveJob events and configure GoodJob's on_thread_error...
...job failures, as they are handled internally by ActiveJob/GoodJob. ActiveSupport::Notifications.subscribe(/(enqueue_retry|retry_stopped|discard)\.active_job/) do |event_name, *, payload| exception = payload[:error] job = payload[:job]
...updates all your gems at once. Given that many gems don't care about stable APIs, this might break your application in a million ways. To stay sane, update your...
...This ensures that your libraries are up-to-date while it's easy to spot major version bumps which may break the app. Projects that have not been updated in...
...not be observable by non-jQuery code. This is currently a WONTFIX for jQuery (see closed issues #2476, #3347). Native events always work for everyone Note that if you trigger...
...listeners using jQuery's trigger(). Note that you might use third-party libraries like select2 that use trigger(). If your entire app is written in jQuery and you don't...
...is a gem for working with daytimes. That's a tuple of (hour, minute second) without a day, month or year. Another additional gem? Thus SQL has a time datatype...
...for storing time of day in the format hh:mm:ss, neither Ruby nor Rails themselves offer an elegant way to deal with day times. Time and DateTime both handle...
PostgreSQL's Common Table Expressions (CTEs) can be used to extract sub-queries from bulky SQL statements into a temporary table to be referenced instead. This is most useful to...
...avoid ugly joins or sub-selects. CTEs can be used for SELECT, INSERT, UPDATE or DELETE. Example From the PostgreSQL docs: WITH regional_sales AS ( SELECT region, SUM(amount) AS...
...block evaluates to true. first_post_with_image = posts.find do |post| post.image end However, sometimes it's not the item you're interested in, but some value depening on it...
...image).find(&:present?).url If the mapping is a costly operation or has undesirable side effects, you need to do it in a single iteration instead. Single iteration solution with...
You have uncommited changes (you can always check by using git status), which you want to discard. Context Now there are several options to discard these depending on...
...your exact situation. The headlines will differentiate the cases whether the files are staged or unstaged. Staged and unstaged changes Staged changes Unstaged Changes Staged and unstaged changes
...the commit which was deployed. If you want to know the currently deployed release, simply SSH to a server and view that file. $ cat /var/www/my-project/current/REVISION cf8734ece3938fc67262ad5e0d4336f820689307 Capistrano task
...application is deployed to multiple servers, you probably want to see a result for all of them. Here is a Capistrano task that checks all servers with the :app role...
Sometimes you need to remove high Unicode characters from a string, so all characters have a code point between 0 and 127. The remaining 7-bit-encoded characters ("Low-ASCII...
...can be transported in most strings where escaping is impossible or would be visually jarrring. Note Transliteration this will change the string. If you need to preserve the exact string...
...want to be in there. In order to reduce the chance to accidentally commit something you didn't intend, review your changes before committing. My preferred way of doing this...
...paths (including new files), but not their contents git add -p Git will now show you all your changes in small chunks and ask you in an interactive mode whether...
min-width is known as a CSS property that can be set to define a least width for an element. Surprisingly, it can also be used to set something that...
...it is more like "auto". This can make block elements take up much more space than desired, even stretching their container beyond the screen edge on small screens.
...just barely wider than the container it should fit into, and it wraps a single word to a new line and it's not really pretty? Cry no more, for...
When browsers encounter a text-wrapping element with text-wrap: balance style, they will try breaking to a new line sooner, if it balances out the width...