giljr

Rails + Tmux + Vim Quick Commands

Sym	Command	Description
🆕	tmux new -t rails	Create and attach a new tmux session named rails
⬆️	vim Gemfile	Open the Gemfile using Vim
⬇️	:tabe spec/rails_helper.rb	Open Rails configuration file in a new Vim tab
⬇️	:tabe spec/rspec_helper.rb	Open RSpec configuration file in a new Vim tab
⌨️	gt	Switch between open Vim tabs
⌨️	Ctrl + b, then Ctrl + Shift + %	Split tmux window into right panel (side-by-side)
⌨️	Ctrl + b → →	Move focus to the **rig

giljr

Concept	Meaning
Chained method	A sub-method added to a custom matcher with chain
Purpose	Extend matcher behavior with extra options or context
Example	expect(user).to have_error_message("can't be blank").on_field(:name)
Config effect	include_chain_clauses_in_custom_matcher_descriptions = true makes RSpec include .on_field(:name) in failure messages

giljr

Line	Meaning
require 'spec_helper'	Loads the basic RSpec configuration.
ENV['RAILS_ENV']	Ensures Rails runs in the test environment.
require_relative '../config/environment'	Loads the Rails application environment.
`abort("The Rails environmen

giljr

Category	👍	💬 Notes
Bundler & vendor	✅	/vendor/* and .bundle correctly ignored.
Environment files	✅	You’re ignoring .env and .env.* — good for security.
Logs & tempfiles	✅	Includes .keep exceptions — perfect for Rails conventions.
PID & storage dirs	✅	Very clean setup for /tmp/pids and /storage.
Public assets	✅	/public/assets is safely ignored — prevents committing precompiled assets.
Credentials	✅	`/config/maste

giljr

Line	Meaning
RSpec.configure do	Opens the RSpec configuration block — all settings go inside this.
config.expect_with :rspec do	Configures how expectations (expect) work.
expectations.include_..._descriptions = true	Improves custom matcher messages by including chained conditions for clearer failure output.
config.mock_with :rspec do	Configures RSpec’s mocking framework.

giljr

Controller Output	Expectation Type	Result
Array of hashes	Array of strings	❌ Fail (structural mismatch)
Array of strings	Array of strings	✅ Pass (matches your current code)

giljr

Form	Example	When to Use
New (symbol)	{ status: 'ok' }	✅ Rails default & preferred
Old (rocket)	{ 'status' => 'ok' }	When keys aren’t symbols (like strings or variables)

giljr

Controller Hash → JSON → RSpec Test

Step	Controller Code Example	JSON Output	RSpec Expectation json = JSON.parse(response.body) (*)json = JSON.parse(response.body, symbolize_names: true)
1. Symbol keys	render json: { status: :ok, code: 200 }	{'status':'ok','code':200}	expect(json['status']).to eq('ok')
2. String keys

giljr

Aspect	Benefit	Possible Drawback
Memory use	Fewer objects	None significant
Performance	Faster for literal-heavy code	Slower if code needs to mutate
Code safety	Prevents accidental mutation	Breaks mutation-based logic
Compatibility	Works fine in modern code	May break older gems
Predictability	Immutable by default	Surprising when global, invisible switch

giljr

Aspect	Effect
Performance	Slightly improved (fewer allocations).
Memory usage	Reduced.
Safety	More immutable code, fewer side effects.
Compatibility	Might break older gems or DSLs relying on mutable strings.
Rails core	Generally safe, but not guaranteed for all gems.