External images in emails can fail in some clients; inline attachments with Rails and attachments.inline keep images visible, but turn messages into multipart emails and use content IDs.

Rails constantize and safe_constantize turn strings into constants, but untrusted input can resolve dangerous classes; validate with an allowlist first.

Side effects are necessary but make Ruby code harder to test and reason about; isolating them reduces coupling and keeps core logic predictable.

Sometimes you inherit a non Rails or non Rack based web app such as PHP, Perl, Java / JEE, etc. I like using cucumber for functional testing so I put together this project structure to use as a starting point for testing non Ruby web based applications.

jqueryElement.is(':checked')

In this article we’ve listed 7 fresh and simple tools for cross-browser compatibility testing, tools that actually make this stuff pretty easy. Not only that, but every single one of these tools can be used for free.

Celerity is a JRuby wrapper around HtmlUnit – a headless Java browser with JavaScript support. It provides a simple API for programmatic navigation through web applications. Celerity aims at being API compatible with Watir.

What do we expect from the custom finder? We expect that it should find assets A, B, C and should not find assets D, E, F. And sometimes the order is important: it should find A, B C with exact order.

Quickly serve a local folder for testing, or boot a Rack app, with one-line commands in Ruby, Python, Passenger, or Puma; HTTPS is possible too.

Web apps fail on devices, browsers, slow networks, large data, and printing when responsive design, loading states, image handling, and metadata are neglected.

html_safe marks strings for unescaped insertion in Rails views, but does not unescape content; misusing it on user input can enable XSS.

RubyMine keyboard shortcuts speed navigation, multi-caret editing, refactoring, and file handling for everyday Ruby development tasks.

YAML.safe_load and YAML.safe_load_file can deep-freeze parsed YAML with freeze: true, keeping configuration data fully immutable; ... .freeze leaves nested objects mutable.

Mailer previews often break when mailer code changes, and automated checks can catch missing updates before they reach development workflows.

AJAX errors in Unpoly can hide the full better_errors page in Rails development. A fallback full-page reload restores the interactive error view and CSS.

Rails-friendly Middleman setup for live reload, asset pipeline, i18n, environment-specific config, browser testing, and Capistrano deployment.

Migrating a larger Rails app from Bootstrap 3 to 4 often breaks styles, components and helper gems; planning library upgrades and rebuilding variables reduces the pain.

Browser defaults are shifting toward SameSite=Lax, making cross-site cookie behavior stricter and exposing iframe, API, and non-GET request flows that need SameSite=None or Strict.

N+1 queries and excessive eager loading can be caught by asserting exact database query counts in specs with the make_database_queries RSpec matcher.

RubyMine Finder searches can return huge result sets; file masks, directory limits, regex, and other filters narrow matches and speed up locating the right code.

Transparent apple-touch-icon images on iOS turn black in Safari, so solid backgrounds prevent ugly home-screen and bookmark icons.

Running one RSpec example without line numbers avoids fragile file-position matches when specs change. Example ids, also called nesting indexes, target the example tree directly.