### Initial `let_it_be` Example

Source: https://test-prof.evilmartians.io/llms-full.txt

Illustrates the initial setup with `let!` for creating test data, which is then improved by `let_it_be`.

```ruby
describe BeatleWeightedSearchQuery do
  let!(:paul) { create(:beatle, name: "Paul") }
  let!(:ringo) { create(:beatle, name: "Ringo") }
  let!(:george) { create(:beatle, name: "George") }
  let!(:john) { create(:beatle, name: "John") }

  specify { expect(subject.call("john")).to contain_exactly(john) }

  # and more examples here
end
```

--------------------------------

### RSpec before_all setup with TestProf

Source: https://test-prof.evilmartians.io/llms-full.txt

This demonstrates the recommended `before_all` usage with TestProf in RSpec. It runs setup code once per example group within a transaction.

```ruby
describe BeatleWeightedSearchQuery do
  before_all do
    @paul = create(:beatle, name: "Paul")
    # ...
  end

  # ...
end
```

--------------------------------

### RSpec before(:all) setup

Source: https://test-prof.evilmartians.io/llms-full.txt

Using `before(:all)` in RSpec for setup. Be aware that this requires careful database cleaning as transactions are not automatically rolled back per example.

```ruby
describe BeatleWeightedSearchQuery do
  before(:all) do
    @paul = create(:beatle, name: "Paul")
    # ...
  end

  # ...
end
```

--------------------------------

### Basic before(:each) setup in RSpec

Source: https://test-prof.evilmartians.io/llms-full.txt

This is a standard RSpec setup using `before(:each)` to create instances before each test. It's less efficient for common setup across many tests.

```ruby
describe BeatleWeightedSearchQuery do
  before(:each) do
    @paul = create(:beatle, name: "Paul")
    @ringo = create(:beatle, name: "Ringo")
    @george = create(:beatle, name: "George")
    @john = create(:beatle, name: "John")
  end

  # and about 15 examples here
end
```

--------------------------------

### Measure Reusable Setup Time

Source: https://test-prof.evilmartians.io/llms-full.txt

Use `RD_PROF=1` to measure time spent in `let`/`before` compared to actual example time using RSpecDissect.

```sh
RD_PROF=1 bin/rspec
```

--------------------------------

### Configure EventProf with Environment Variable for Examples

Source: https://test-prof.evilmartians.io/llms-full.txt

Alternatively, set the EVENT_PROF_EXAMPLES=1 environment variable to profile individual test examples.

```sh
EVENT_PROF_EXAMPLES=1
```

--------------------------------

### MemoryProf Example Output

Source: https://test-prof.evilmartians.io/llms-full.txt

Example output of MemoryProf showing RSS usage for groups and examples.

```sh
[TEST PROF INFO] MemoryProf results

Final RSS: 673KB

Top 5 groups (by RSS):

AnswersController (./spec/controllers/answers_controller_spec.rb:3) – +80KB (13.50%)
QuestionsController (./spec/controllers/questions_controller_spec.rb:3) – +32KB  (9.08%)
CommentsController (./spec/controllers/comments_controller_spec.rb:3) – +16KB (3.27%)

Top 5 examples (by RSS):

destroys question (./spec/controllers/questions_controller_spec.rb:38) – +144KB (24.38%)
change comments count (./spec/controllers/comments_controller_spec.rb:7) – +120KB (20.00%)
change Votes count (./spec/shared_examples/controllers/voted_examples.rb:23) – +90KB (16.36%)
change Votes count (./spec/shared_examples/controllers/voted_examples.rb:23) – +64KB (12.86%)
fails (./spec/shared_examples/controllers/invalid_examples.rb:3) – +32KB (5.00%)
```

--------------------------------

### FactoryDoctor Report Example

Source: https://test-prof.evilmartians.io/llms-full.txt

An example output from FactoryDoctor, highlighting potentially inefficient test examples and the time wasted.

```sh
[TEST PROF INFO] FactoryDoctor report

Total (potentially) bad examples: 2
Total wasted time: 00:13.165

User (./spec/models/user_spec.rb:3) (3 records created, 00:00.628)
  validates name (./spec/user_spec.rb:8) – 1 record created, 00:00.114
  validates email (./spec/user_spec.rb:8) – 2 records created, 00:00.514
```

--------------------------------

### Example RSpecDissect Output

Source: https://test-prof.evilmartians.io/llms-full.txt

This output shows the total time spent in `before(:each)` hooks and `let` declarations, along with the top slowest example groups and `let` usage within those groups.

```sh
[TEST PROF INFO] RSpecDissect enabled

Total time: 25:14.870
Total `before(:each)` time: 14:36.482
Total `let` time: 19:20.259

Top 5 slowest suites (by `before(:each)` time):

Webhooks::DispatchTransition (./spec/services/webhooks/dispatch_transition_spec.rb:3) – 00:29.895 of 00:33.706 (327)
FunnelsController (./spec/controllers/funnels_controller_spec.rb:3) – 00:22.117 of 00:43.649 (133)
ApplicantsController (./spec/controllers/applicants_controller_spec.rb:3) – 00:21.220 of 00:41.407 (222)
BookedSlotsController (./spec/controllers/booked_slots_controller_spec.rb:3) – 00:15.729 of 00:27.893 (50)
Analytics::Wor...rsion::Summary (./spec/services/analytics/workflow_conversion/summary_spec.rb:3) – 00:15.383 of 00:15.914 (12)


Top 5 slowest suites (by `let` time):

FunnelsController (./spec/controllers/funnels_controller_spec.rb:3) – 00:38.532 of 00:43.649 (133)
 ↳ user – 3
 ↳ funnel – 2
ApplicantsController (./spec/controllers/applicants_controller_spec.rb:3) – 00:33.252 of 00:41.407 (222)
 ↳ user – 10
 ↳ funnel – 5
 ↳ applicant – 2
Webhooks::DispatchTransition (./spec/services/webhooks/dispatch_transition_spec.rb:3) – 00:30.320 of 00:33.706 (327)
 ↳ user – 30
BookedSlotsController (./spec/controllers/booked_slots_controller_spec.rb:3) – 00:25.710 of 00:27.893 e(50)
 ↳ user – 21
 ↳ stage – 14
AvailableSlotsController (./spec/controllers/available_slots_controller_spec.rb:3) – 00:18.481 of 00:23.366 (85)
 ↳ user – 15
 ↳ stage – 10

```

--------------------------------

### Add StackProf Gem

Source: https://test-prof.evilmartians.io/llms-full.txt

Install the `stackprof` gem, which is recommended for general profiling.

```sh
bundle add stackprof
```

--------------------------------

### Install Profiling Gems

Source: https://test-prof.evilmartians.io/llms-full.txt

Install StackProf or Vernier gems using Bundler. These are recommended for general profiling of Ruby applications.

```sh
bundle add stackprof
```

```sh
# or
bundle add vernier
```

--------------------------------

### Using `before_all` for Test Data Setup

Source: https://test-prof.evilmartians.io/llms-full.txt

An alternative approach using `before_all` to set up shared test data, which requires using instance variables and defining all data at once.

```ruby
describe BeatleWeightedSearchQuery do
  before_all do
    @paul = create(:beatle, name: "Paul")
    # ...
  end

  specify { expect(subject.call("joh")).to contain_exactly(@john) }

  # ...
end
```

--------------------------------

### AnyFixture DSL Setup for Minitest

Source: https://test-prof.evilmartians.io/llms-full.txt

Include the AnyFixture DSL in a base Minitest class to use the `fixture` method and callbacks.

```ruby
require "test_prof/any_fixture/dsl"

class MyBaseTestCase < Minitest::Test
  include TestProf::AnyFixture::DSL
end
```

--------------------------------

### Minitest integration with TestProf BeforeAll

Source: https://test-prof.evilmartians.io/llms-full.txt

This example shows how to integrate `before_all` with Minitest. It requires including `TestProf::BeforeAll::Minitest` and defining the `before_all` block.

```ruby
require "test_prof/recipes/minitest/before_all"

class MyBeatlesTest < Minitest::Test
  include TestProf::BeforeAll::Minitest

  before_all do
    @paul = create(:beatle, name: "Paul")
    @ringo = create(:beatle, name: "Ringo")
    @george = create(:beatle, name: "George")
    @john = create(:beatle, name: "John")
  end

  # define tests which could access the object defined within `before_all`
end
```

--------------------------------

### TagProf Output Example (with SQL events)

Source: https://test-prof.evilmartians.io/llms-full.txt

Example output of TagProf report when profiling SQL events, showing time spent on 'sql.active_record' per type.

```sh
[TEST PROF INFO] TagProf report for type

       type          time   sql.active_record  total  %total   %time           avg

    request     00:04.808           00:01.402     42   33.87   54.70     00:00.114
 controller     00:02.855           00:00.921     42   33.87   32.48     00:00.067
      model     00:01.127           00:00.446     40   32.26   12.82     00:00.028
```

--------------------------------

### Factory Stack Example

Source: https://test-prof.evilmartians.io/llms-full.txt

Illustrates a sequence of factory creation calls and their resulting stack. Wider columns indicate higher frequency of a stack's appearance.

```ruby
factory :comment do
  answer
  author
end

factory :answer do
  question
  author
end

factory :question do
  author
end

create(:comment) #=> creates 5 records

# And the corresponding stack is:
# [:comment, :answer, :question, :author, :author, :author]
```

--------------------------------

### Minitest Setup for AnyFixture

Source: https://test-prof.evilmartians.io/llms-full.txt

Require AnyFixture and ensure database cleanup after each test run by calling TestProf::AnyFixture.clean at exit.

```ruby
require "test_prof/any_fixture"

at_exit { TestProf::AnyFixture.clean }
```

--------------------------------

### Using Fixture Callbacks

Source: https://test-prof.evilmartians.io/llms-full.txt

Define callbacks to run before or after fixtures are reset, useful for custom cleanup or setup.

```ruby
before_fixtures_reset { Post.delete_all }
after_fixtures_reset { Post.delete_all }
```

--------------------------------

### TagProf Output Example (Basic)

Source: https://test-prof.evilmartians.io/llms-full.txt

Example output of TagProf report showing test statistics grouped by type, including time, count, and average.

```sh
[TEST PROF INFO] TagProf report for type

       type          time   total  %total   %time           avg

    request     00:04.808      42   33.87   54.70     00:00.114
 controller     00:02.855      42   33.87   32.48     00:00.067
      model     00:01.127      40   32.26   12.82     00:00.028
```

--------------------------------

### Enable Per-Example Profiling in EventProf

Source: https://test-prof.evilmartians.io/llms-full.txt

Set `config.per_example = true` to profile individual examples instead of just top-level groups. Alternatively, use the `EVENT_PROF_EXAMPLES=1` environment variable.

```ruby
TestProf::EventProf.configure do |config|
  config.per_example = true
end
```

--------------------------------

### Run FactoryDoctor with FactoryAllStub Stamp

Source: https://test-prof.evilmartians.io/llms-full.txt

Use this command to run FactoryDoctor and automatically mark all problematic examples with the `factory:stub` stamp, facilitating quick fixes.

```sh
# Run FactoryDoctor and mark all offensive examples with factory:stub
FDOC=1 FDOC_STAMP=factory:stub rspec ./spec/models

```

--------------------------------

### Register Dump with Before Hook for Tenant Creation

Source: https://test-prof.evilmartians.io/llms-full.txt

Use a 'before' hook to perform actions like creating a tenant before a fixture dump is processed. This example ensures a 'test' tenant exists.

```ruby
TestProf::AnyFixture.register_dump(
  "account",
  before: proc do
    begin
      Apartment::Tenant.create("test")
    rescue
      nil
    end
    Apartment::Tenant.create("test")
  end
) do
  # ...
end
```

--------------------------------

### Use FactoryAllStub with RSpec Examples

Source: https://test-prof.evilmartians.io/llms-full.txt

Mark specific RSpec examples or groups with `factory: :stub` to enforce the `build_stubbed` strategy, overriding the default `create` behavior.

```ruby
describe "User" do
  let(:user) { create(:user) }

  it "is valid", factory: :stub do
    # use `build_stubbed` instead of `create`
    expect(user).to be_valid
  end
end

```

--------------------------------

### TagProf Minitest Unknown Grouping Example

Source: https://test-prof.evilmartians.io/llms-full.txt

Example output for Minitest when TagProf cannot determine test file locations, showing an '__unknown__' group.

```sh
[TEST PROF INFO] TagProf report for type

       type          time   sql.active_record  total  %total   %time           avg

__unknown__     00:04.808           00:01.402     42   33.87   54.70     00:00.114
 controller     00:02.855           00:00.921     42   33.87   32.48     00:00.067
      model     00:01.127           00:00.446     40   32.26   12.82     00:00.028
```

--------------------------------

### Profile Individual Examples with StackProf

Source: https://test-prof.evilmartians.io/llms-full.txt

Use the :sprof metadata tag in RSpec examples to profile them individually. Note that this does not work when global (per-suite) profiling is active.

```ruby
it "is doing heavy stuff", :sprof do
  # ...
end
```

--------------------------------

### Define Factories with Associations

Source: https://test-prof.evilmartians.io/llms-full.txt

Example of defining factories with associations using FactoryBot.

```ruby
factory :account do
end

factory :user do
  account
end

factory :project do
  account
  user
end

factory :task do
  account
  project
  user
end
```

--------------------------------

### Basic `let_it_be` Usage in Tests

Source: https://test-prof.evilmartians.io/llms-full.txt

Example of using `let_it_be` within a test suite after requiring the recipe.

```ruby
describe MySuperDryService do
  let_it_be(:user) { create(:user) }

  # ...
end
```

--------------------------------

### Set Factory Default Methods

Source: https://test-prof.evilmartians.io/llms-full.txt

Examples of using `set_factory_default` to define default records for factories.

```ruby
let(:user) { create(:user) }

before { FactoryBot.set_factory_default(:user, user) }

# You can also set the default factory with traits
FactoryBot.set_factory_default([:user, :admin], admin)

# Or (since v1.4)
FactoryBot.set_factory_default(:user, :admin, admin)

# You can also register a default record for specific attribute overrides
Fabricate.set_fabricate_default(:post, post, state: "draft")
```

--------------------------------

### Define Factories with Fabrication

Source: https://test-prof.evilmartians.io/llms-full.txt

Example of defining factories with associations using Fabrication.

```ruby
Fabricator(:account) do
end

Fabricator(:user) do
  account
end
```

--------------------------------

### Collect SQL Queries with EventProf (Minitest)

Source: https://test-prof.evilmartians.io/llms-full.txt

Use the EVENT_PROF environment variable to collect SQL query statistics for every suite and example when running Minitest.

```sh
EVENT_PROF='sql.active_record' rake test
```

--------------------------------

### Minitest Setup for AnyFixture

Source: https://test-prof.evilmartians.io/llms-full.txt

When using AnyFixture with Minitest, ensure you manually clean the database after each test run by calling `TestProf::AnyFixture.clean` at exit.

```ruby
# test_helper.rb

require "test_prof/any_fixture"

at_exit { TestProf::AnyFixture.clean }
```

--------------------------------

### AnyFixture DSL Setup for RSpec

Source: https://test-prof.evilmartians.io/llms-full.txt

Include the AnyFixture DSL in RSpec configuration to use the `fixture` method and callbacks.

```ruby
require "test_prof/any_fixture/dsl"

RSpec.configure do |config|
  config.include TestProf::AnyFixture::DSL
end
```

--------------------------------

### Integrate EventProf with RSpecStamp

Source: https://test-prof.evilmartians.io/llms-full.txt

Use `EVENT_PROF` and `EVENT_PROF_STAMP` environment variables to mark slow examples with custom tags. This example marks slow SQL events.

```sh
EVENT_PROF="sql.active_record" EVENT_PROF_STAMP="slow:sql" rspec ...
```

--------------------------------

### Ensuring multiple database connections are loaded

Source: https://test-prof.evilmartians.io/llms-full.txt

To use `before_all` with multiple database connections, ensure all relevant connection classes are loaded before tests run. This example shows loading `ApplicationRecord` and `AccountsRecord`.

```ruby
class Users < AccountsRecord
  # ...
end

class Articles < ApplicationRecord
  # ...
end
```

```ruby
# Ensure connection classes are loaded
ApplicationRecord
AccountsRecord
```

--------------------------------

### Explicitly Tagging for Frost Mode

Source: https://test-prof.evilmartians.io/llms-full.txt

You can tag individual contexts or examples with `:let_it_be_frost` to enable the frost mode for that specific scope.

```ruby
context "with frost mode enabled", let_it_be_frost: true do
  # ...
end
```

--------------------------------

### Register a Fixture with ActiveRecord

Source: https://test-prof.evilmartians.io/llms-full.txt

Register a fixture named 'account' using plain ActiveRecord to create the data. This demonstrates direct database manipulation for fixture setup.

```ruby
TestProf::AnyFixture.register(:account) do
  # ...
  # or with plain old AR
  Account.create!(name: "test")
end
```

--------------------------------

### FactoryBot: Validate Name Presence (Good)

Source: https://test-prof.evilmartians.io/llms-full.txt

This example demonstrates an optimized test using FactoryBot's `build_stubbed` method, avoiding unnecessary database writes.

```ruby
# with FactoryBot/FactoryGirl
it "validates name presence" do
  user = build_stubbed(:user)
  user.name = ""
  expect(user).not_to be_valid
end
```

--------------------------------

### Configure Strict Mode Thresholds

Source: https://test-prof.evilmartians.io/llms-full.txt

In strict mode, configure environment variables to set thresholds for failing builds. These include maximum examples, maximum time, and minimum TPS.

```sh
TPS_PROF=strict TPS_PROF_MAX_EXAMPLES=50 rspec
```

```sh
TPS_PROF=strict TPS_PROF_MAX_TIME=30 rspec
```

```sh
TPS_PROF=strict TPS_PROF_MIN_TPS=5 rspec
```

```sh
TPS_PROF=strict TPS_PROF_MIN_TPS=5 TPS_PROF_MAX_TIME=30 rspec
```

--------------------------------

### Generate StackProf Reports with Suffixes

Source: https://test-prof.evilmartians.io/llms-full.txt

Use the TEST_PROF_REPORT environment variable to add custom suffixes to report filenames, useful for comparing different test setups. This example shows generating reports with and without 'bootsnap'.

```sh
# Generate first report using `-with-bootsnap` suffix
$ TEST_STACK_PROF=boot TEST_PROF_REPORT=with-bootsnap bundle exec rake
$ #=> StackProf report generated: tmp/test_prof/stack-prof-report-wall-raw-boot-with-bootsnap.dump

# Assume that you disabled bootsnap and want to generate a new report
$ TEST_STACK_PROF=boot TEST_PROF_REPORT=no-bootsnap bundle exec rake
$ #=> StackProf report generated: tmp/test_prof/stack-prof-report-wall-raw-boot-no-bootsnap.dump
```

--------------------------------

### Configure EventProf Ranking

Source: https://test-prof.evilmartians.io/llms-full.txt

Use the `EVENT_PROF_RANK` environment variable to sort profiling statistics by event count or time spent. Example shown for sorting by count.

```sh
EVENT_PROF_RANK=count EVENT_PROF='instantiation.active_record' be rspec
```

--------------------------------

### Show EventProf CLI Help

Source: https://test-prof.evilmartians.io/llms-full.txt

Display the list of possible command-line options for EventProf.

```sh
ruby test/my_super_test.rb --help
```

--------------------------------

### Display Minitest Help with EventProf Options

Source: https://test-prof.evilmartians.io/llms-full.txt

To see a list of available options for EventProf when running Minitest, use the `--help` flag.

```sh
# Show the list of possible options:
ruby test/my_super_test.rb --help
```

--------------------------------

### Enable Global StackProf Profiling

Source: https://test-prof.evilmartians.io/llms-full.txt

Activate StackProf profiling for your entire test suite by setting the TEST_STACK_PROF environment variable. This is a simple way to start profiling.

```sh
TEST_STACK_PROF=1 bundle exec rake test
```

--------------------------------

### Implement Custom Database Adapter for BeforeAll

Source: https://test-prof.evilmartians.io/llms-full.txt

Create a custom adapter by implementing `begin_transaction` and `rollback_transaction` methods. Configure BeforeAll to use your custom adapter.

```ruby
class MyDBAdapter
  # before_all adapters must implement two methods:
  # - begin_transaction
  # - rollback_transaction
  def begin_transaction
    # ...
  end

  def rollback_transaction
    # ...
  end
end

# And then set adapter for `BeforeAll` module
TestProf::BeforeAll.adapter = MyDBAdapter.new
```

--------------------------------

### Profile Individual RSpec Examples with RubyProf

Source: https://test-prof.evilmartians.io/llms-full.txt

Profile specific RSpec examples by adding the :rprof tag to the example. Note that per-example profiling is not compatible with global profiling.

```ruby
it "is doing heavy stuff", :rprof do
  # ...
end
```

--------------------------------

### Tag Slow Factory Tests with EventProf and EVEN_PROF_STAMP

Source: https://test-prof.evilmartians.io/llms-full.txt

Automatically tag the slowest examples based on factory creation time. Use EVENT_PROF=factory.create and EVEN_PROF_STAMP=slow:factory to mark these tests for further analysis.

```sh
EVENT_PROF=factory.create EVEN_PROF_STAMP=slow:factory bin/rspec spec/models
```

--------------------------------

### Mark Slowest Examples with Custom Tag

Source: https://test-prof.evilmartians.io/llms-full.txt

Automatically mark the slowest examples with a custom tag like `slow:factory` in RSpec.

```sh
EVENT_PROF=factory.create EVENT_PROF_STAMP=slow:factory bin/rspec spec/models
```

--------------------------------

### Registering SQL Dump for Test Data

Source: https://test-prof.evilmartians.io/llms-full.txt

Use `register_dump` to optimize test data setup by generating an SQL dump. This is useful for large datasets or performance-critical tests. The block is executed only if the SQL dump is missing, and subsequent runs restore data from the dump.

```ruby
RSpec.shared_context "account", account: true do
  # You should call AnyFixture outside of transaction to re-use the same
  # data between examples
  before(:all) do
    # The block is called once per test run (similary to #register)
    TestProf::AnyFixture.register_dump("account") do
      # Do anything here, AnyFixture keeps track of affected DB tables
      # For example, you can use factories here
      account = FactoryGirl.create(:account, name: "test")

      # or with Fabrication
      account = Fabricate(:account, name: "test")

      # or with plain old AR
      account = Account.create!(name: "test")

      # updates are also tracked
      account.update!(tag: "sql-dump")
    end
  end

 # Here, we MUST use a custom way to retrieve a record: since we restore the data
 # from a plain SQL dump, we have no knowledge of Ruby objects
  let(:account) { Account.find_by!(name: "test") }
end
```

--------------------------------

### Using FactoryDefault with `let_it_be`

Source: https://test-prof.evilmartians.io/llms-full.txt

Defaults created within `before_all` and `let_it_be` are not reset after each example, but only at the end of the corresponding example group. RSpec only.

```ruby
# Using with `before_all` / `let_it_be`

# Defaults created within `before_all` and `let_it_be` are not reset after each example, but only at the end of the corresponding example group. So, it's possible to call `create_default` within `let_it_be` without any additional configuration. **RSpec only**

**IMPORTANT:** You must load FactoryDefault after loading BeforeAll to make this feature work.

**NOTE**. Regular `before(:all)` callbacks are not supported.
```

--------------------------------

### Profile Application Boot with StackProf

Source: https://test-prof.evilmartians.io/llms-full.txt

Profile the application boot process by setting TEST_STACK_PROF to 'boot' and specifying a test file. This helps identify performance bottlenecks during application initialization.

```sh
# pick some random spec (1 is enough)
$ TEST_STACK_PROF=boot bundle exec rspec ./spec/some_spec.rb
```

--------------------------------

### Configure Factory Logging

Source: https://test-prof.evilmartians.io/llms-full.txt

Use `factory.create` report to narrow down scope to top files when using factories.

```sh
EVENT_PROF=factory.create bin/rspec spec/models
```

--------------------------------

### Minitest: Ignore Specific Example

Source: https://test-prof.evilmartians.io/llms-full.txt

Shows how to ignore a Minitest example from FactoryDoctor's analysis using the `fd_ignore` method within the test.

```ruby
# won't be reported as offense
it "is ignored" do
  fd_ignore

  @user.name = ""
  refute @user.valid?
end
```

--------------------------------

### Initialize FactoryAllStub

Source: https://test-prof.evilmartians.io/llms-full.txt

Call this method to initialize FactoryAllStub, injecting its custom logic into the FactoryBot generator. This is required for manual control.

```ruby
TestProf::FactoryAllStub.init

```

--------------------------------

### Profile Individual Examples with Vernier

Source: https://test-prof.evilmartians.io/llms-full.txt

Use the :vernier metadata tag in RSpec examples to profile them individually. This feature is not available when global profiling is active.

```ruby
it "is doing heavy stuff", :vernier do
  # ...
end
```

--------------------------------

### RSpec Example with Aggregate Failures

Source: https://test-prof.evilmartians.io/llms-full.txt

This RSpec example demonstrates how to use `:aggregate_failures` to collect all failures within a test. It also shows how to explicitly check headers and status codes.

```ruby
it "returns the second page", :aggregate_failures do
  is_expected.to be_success
  is_expected.to have_header("X-TOTAL-PAGES", 10)
  is_expected.to have_header("X-NEXT-PAGE", 2)
  expect(subject.status).to eq(200)
end
```

--------------------------------

### Create Default Shortcut

Source: https://test-prof.evilmartians.io/llms-full.txt

Using `create_default` as a shortcut for `create` and `set_factory_default`.

```ruby
# FactoryBot#create_default(...) / Fabricate.create_default(...)
# is a shortcut for `create` + `set_factory_default`.
```

--------------------------------

### FactoryDefault Cleanup Behavior

Source: https://test-prof.evilmartians.io/llms-full.txt

Defaults are cleaned up after each example by default when using `test_prof/recipes/rspec/factory_default`.

```ruby
# IMPORTANT: Defaults are **cleaned up after each example** by default (i.e., when using `test_prof/recipes/rspec/factory_default`).
```

--------------------------------

### Using FactoryDefault for Associations

Source: https://test-prof.evilmartians.io/llms-full.txt

Demonstrates using `create_default` to simplify association creation with FactoryDefault.

```ruby
describe "PATCH #update" do
  let(:account) { create_default(:account) }
  let(:project) { create_default(:project) }
  let(:task) { create(:task) }

  # and if we need more projects, users, tasks with the same parent record,
  # we just write
  let(:another_project) { create(:project) } # uses the same account
  let(:another_task) { create(:task) } # uses the same account

  it "works" do
    patch :update, id: task.id, task: {completed: "t"}
    expect(response).to be_success
  end
end
```

--------------------------------

### Configure Global Before and After Dump Hooks

Source: https://test-prof.evilmartians.io/llms-full.txt

Set up global hooks that execute before or after dump operations. The 'before_dump' hook receives dump information and an import flag, while 'after_dump' also provides dump details and can check for success.

```ruby
TestProf::AnyFixture.configure do |config|
  config.before_dump do |dump:, import:|
    # dump is an object containing information about the dump (e.g., dump.digest)
    # import is true if we're restoring a dump and false otherwise
    # do something
  end

  config.after_dump do |dump:, import:|
    # ...
  end
end
```

--------------------------------

### Run Specific File with EventProf CLI (Minitest)

Source: https://test-prof.evilmartians.io/llms-full.txt

Execute a specific test file using the --event-prof CLI option to collect SQL query statistics.

```sh
ruby test/my_super_test.rb --event-prof=sql.active_record
```

--------------------------------

### Get Factory Default Method

Source: https://test-prof.evilmartians.io/llms-full.txt

Retrieving the default value for a factory using `get_factory_default`.

```ruby
# FactoryBot#get_factory_default(factory) / Fabricate.get_fabricate_default(factory) – retrieves the default value for `factory` (since v1.4).

# This method also supports traits
admin = FactoryBot.get_factory_default(:user, :admin)
```

--------------------------------

### Minitest MemoryProf CLI Configuration Top Count

Source: https://test-prof.evilmartians.io/llms-full.txt

Configure the number of top examples/groups to display for Minitest using CLI options.

```sh
# Run a specific file using CLI option
ruby test/my_super_test.rb --mem-prof=rs --mem-prof-top-count=10
```

--------------------------------

### Initializing FactoryAllStub

Source: https://test-prof.evilmartians.io/llms-full.txt

Code to initialize FactoryAllStub, which injects custom logic into FactoryBot's generator to enable all-stub mode.

```ruby
TestProf::FactoryAllStub.init
```

--------------------------------

### Handling Traits with FactoryDefault

Source: https://test-prof.evilmartians.io/llms-full.txt

Demonstrates how FactoryDefault interacts with traits and how to configure it to preserve traits.

```ruby
factory :comment do
  user
end

factory :post do
  association :user, factory: %i[user able_to_post]
end

factory :view do
  association :user, factory: %i[user unable_to_post_only_view]
end

# If there is a default value for the `user` factory, it's gonna be used independently of traits. This may break your logic.
# To prevent this, configure FactoryDefault to preserve traits:

# Globally
TestProf::FactoryDefault.configure do |config|
  config.preserve_traits = true
end

# or in-place
create_default(:user, preserve_traits: true)

# Creating a default with trait works as follows:

# Create a default with trait
user = create_default(:user_poster, :able_to_post)

# When an association has no traits specified, the default with trait is used
create(:comment).user == user #=> true
# When an association has the matching trait specified, the default is used, too
create(:post).user == user #=> true
```

--------------------------------

### Activate FactoryProf with Variations and Limit

Source: https://test-prof.evilmartians.io/llms-full.txt

Run FactoryProf with variations enabled and a limit on the number of variations displayed by setting FPROF=1 and FPROF_VARIATIONS_LIMIT=N environment variables.

```sh
FPROF=1 FPROF_VARIATIONS_LIMIT=5 rspec
```

```sh
FPROF=1 FPROF_VARIATIONS_LIMIT=5 bundle exec rake test
```

--------------------------------

### Integrating FactoryDoctor with RSpecStamp

Source: https://test-prof.evilmartians.io/llms-full.txt

Example of using FactoryDoctor with RSpecStamp to automatically tag potentially bad test cases with a custom tag.

```sh
FDOC=1 FDOC_STAMP="fdoc:consider" rspec ...
```

--------------------------------

### Enabling AnyFixture DSL with Refinement

Source: https://test-prof.evilmartians.io/llms-full.txt

Use `using TestProf::AnyFixture::DSL` to enable syntactic sugar for defining fixtures and callbacks, allowing the use of `fixture` and `before_fixtures_reset`/`after_fixtures_reset` methods.

```ruby
require "test_prof/any_fixture/dsl"

# Enable DSL
using TestProf::AnyFixture::DSL

# and then you can use `fixture` method (which is just an alias for `TestProf::AnyFixture.register`)
before(:all) { fixture(:account) }

# You can also use it to fetch the record (instead of storing it in instance variable)
let(:account) { fixture(:account) }

# You can just use `before_fixtures_reset` or `after_fixtures_reset` callbacks
before_fixtures_reset { Post.delete_all }
after_fixtures_reset { Post.delete_all }
```

--------------------------------

### Fabrication: Ignore Specific Example

Source: https://test-prof.evilmartians.io/llms-full.txt

Demonstrates how to ignore a specific test case from FactoryDoctor's analysis by adding the `:fd_ignore` tag.

```ruby
# won't be reported as offense
it "is ignored", :fd_ignore do
  user = create(:user)
  user.name = ""
  expect(user).not_to be_valid
end
```

--------------------------------

### Add ruby-prof to Gemfile

Source: https://test-prof.evilmartians.io/llms-full.txt

Ensure the ruby-prof gem is installed by adding it to your Gemfile. It's recommended to require it only for development and test environments.

```ruby
# Gemfile
group :development, :test do
  gem "ruby-prof", ">= 1.4.0", require: false
end
```

--------------------------------

### AnyFixture DSL for Fixture Definition

Source: https://test-prof.evilmartians.io/llms-full.txt

Use the optional DSL for a more concise way to define fixtures. Enable the DSL using `using TestProf::AnyFixture::DSL` and then use the `fixture` method as an alias for `TestProf::AnyFixture.register`.

```ruby
require "test_prof/any_fixture/dsl"

# Enable DSL
using TestProf::AnyFixture::DSL

# and then you can use `fixture` method (which is just an alias for `TestProf::AnyFixture.register`)
before(:all) { fixture(:account) }

# You can also use it to fetch the record (instead of storing it in instance variable)
let(:account) { fixture(:account) }
```

--------------------------------

### Ignore Groups or Examples with TPSProf

Source: https://test-prof.evilmartians.io/llms-full.txt

Exclude specific RSpec groups from TPSProf tracking by adding the `tps_prof: :ignore` metadata to the group definition.

```ruby
RSpec.describe "SlowButOk", tps_prof: :ignore do
  # ...
end
```

--------------------------------

### Create Default Factory Object

Source: https://test-prof.evilmartians.io/llms-full.txt

Use `create_default` as a shortcut for `create` and `set_factory_default`.

```ruby
create_default(:user)
```

--------------------------------

### Configure AnyFixture CLI Import

Source: https://test-prof.evilmartians.io/llms-full.txt

Determine whether AnyFixture should attempt to use command-line tools (like psql or sqlite3) for restoring dumps, or use ActiveRecord instead. Using CLI tools prevents tracking affected tables for cleanup.

```ruby
TestProf::AnyFixture.configure do |config|
  # ...
  # Whether to try using CLI tools such as psql or sqlite3 to restore dumps or not (and use ActiveRecord instead)
  config.import_dump_via_cli = false
end
```

--------------------------------

### Use Refind Modifier with LetItBe

Source: https://test-prof.evilmartians.io/llms-full.txt

Employ the `refind: true` modifier to hard-reload records, ensuring they are fetched from the database in their pristine state for each example.

```ruby
# You can also specify refind: true option to hard-reload the record
let_it_be(:user, refind: true) { create(:user) }

# it is almost equal to
before_all { @user = create(:user) }
let(:user) { User.find(@user.id) }
```

--------------------------------

### Configuring AnyFixture Dumps Directory and Import Behavior

Source: https://test-prof.evilmartians.io/llms-full.txt

Customize AnyFixture's behavior by setting the dumps directory, configuring which queries to include in dumps, and choosing whether to use CLI tools for restoring dumps.

```ruby
TestProf::AnyFixture.configure do |config|
  # Where to store dumps (by default, TestProf.artifact_path + '/any_dumps')
  config.dumps_dir = "any_dumps"
  # Include mathing queries into a dump (in addition to INSERT/UPDATE/DELETE queries)
  config.dump_matching_queries = /^$/
  # Whether to try using CLI tools such as psql or sqlite3 to restore dumps or not (and use ActiveRecord instead)
  config.import_dump_via_cli = false
end
```

--------------------------------

### FactoryBot: Validate Name Presence (Bad)

Source: https://test-prof.evilmartians.io/llms-full.txt

This example shows an inefficient test using FactoryBot where a user record is created in the database unnecessarily.

```ruby
# with FactoryBot/FactoryGirl
it "validates name presence" do
  user = create(:user)
  user.name = ""
  expect(user).not_to be_valid
end
```

--------------------------------

### Enable Rails Fixtures in BeforeAll Hooks

Source: https://test-prof.evilmartians.io/llms-full.txt

Opt-in to using fixtures within `before_all` hooks by setting `setup_fixture: true` or globally via `TestProf::BeforeAll.configure`.

```ruby
before_all(setup_fixtures: true) do
  @user = users(:john)
  @post = create(:post, user: user)
end
```

```ruby
TestProf::BeforeAll.configure do |config|
  config.setup_fixtures = true
end
```

--------------------------------

### Fabrication: Validate Name Presence (Bad)

Source: https://test-prof.evilmartians.io/llms-full.txt

This example demonstrates an inefficient test using Fabrication where a user record is created in the database unnecessarily.

```ruby
it "validates name presence" do
  user = Fabricate.build(:user)
  user.name = ""
  expect(user).not_to be_valid
end
```

--------------------------------

### Manually Enable/Disable Shared Connection

Source: https://test-prof.evilmartians.io/llms-full.txt

Use these methods to programmatically control the shared connection mode. This is useful for specific test setups or debugging.

```ruby
TestProf::ActiveRecordSharedConnection.enable!
```

```ruby
TestProf::ActiveRecordSharedConnection.disable!
```

--------------------------------

### Profile Application Boot with Vernier

Source: https://test-prof.evilmartians.io/llms-full.txt

Profile the application boot process with Vernier by setting TEST_VERNIER to 'boot' and specifying a test file. This is useful for diagnosing startup performance issues.

```sh
# pick some random spec (1 is enough)
TEST_VERNIER=boot bundle exec rspec ./spec/some_spec.rb
```

--------------------------------

### Configure FactoryDefault to Report Summary

Source: https://test-prof.evilmartians.io/llms-full.txt

Enable the reporting of FactoryDefault usage statistics globally. This helps in understanding how often default factories are being utilized.

```ruby
TestProf::FactoryDefault.configure do |config|
  config.report_summary = true
  # Report stats prints the detailed usage information (including summary)
  config.report_stats = true
end
```

--------------------------------

### Enable Transactional Fixtures in RSpec Rails

Source: https://test-prof.evilmartians.io/llms-full.txt

To ensure database rollback between RSpec examples, enable `use_transactional_fixtures` in your `spec/rails_helper.rb`. This is crucial for isolated test runs.

```ruby
RSpec.configure do |config|
  config.use_transactional_fixtures = true # RSpec takes care to use `use_transactional_tests` or `use_transactional_fixtures` depending on the Rails version used
end
```

--------------------------------

### Use RSpecDissect with RSpecStamp

Source: https://test-prof.evilmartians.io/llms-full.txt

Integrate RSpecDissect with RSpecStamp to automatically tag slow examples. Set `RD_PROF_STAMP` to a desired tag name when running RSpec with `RD_PROF=1`.

```sh
RD_PROF=1 RD_PROF_STAMP="slow" rspec ...

```

--------------------------------

### Activate EventProf with Minitest

Source: https://test-prof.evilmartians.io/llms-full.txt

For Minitest 6+, first load the TestProf plugin in your test helper. Then, use the `EVENT_PROF` environment variable set to the event name to collect profiling data.

```sh
# Collect SQL queries stats for every suite and example
EVENT_PROF='sql.active_record' rake test
```

--------------------------------

### Run Sampling Tests

Source: https://test-prof.evilmartians.io/llms-full.txt

Run multiple subsets of tests with `SAMPLE=100` to reveal application-wide problems and analyze the obtained flamegraphs.

```sh
SAMPLE=100 bin/rails test
```

--------------------------------

### Use Reload Modifier with LetItBe

Source: https://test-prof.evilmartians.io/llms-full.txt

Utilize the `reload: true` modifier to ensure objects are re-initialized for each example, preventing state leakage. This is useful for ActiveRecord instances.

```ruby
# Use reload: true option to reload user object (assuming it's an instance of ActiveRecord)
# for every example
let_it_be(:user, reload: true) { create(:user) }

# it is almost equal to
before_all { @user = create(:user) }
let(:user) { @user.reload }
```

--------------------------------

### Configure TestProf Global Settings

Source: https://test-prof.evilmartians.io/llms-full.txt

Set the directory for artifacts, enable unique filenames and color output, and specify where logs should be written. You can also provide a custom logger instance.

```ruby
TestProf.configure do |config|
  # the directory to put artifacts (reports) in ('tmp/test_prof' by default)
  config.output_dir = "tmp/test_prof"

  # use unique filenames for reports (by simply appending current timestamp)
  config.timestamps = true

  # color output
  config.color = true

  # where to write logs (defaults)
  config.output = $stdout

  # alternatively, you can specify a custom logger instance
  config.logger = MyLogger.new
end
```

--------------------------------

### Measure Factory Default Summary

Source: https://test-prof.evilmartians.io/llms-full.txt

Use `FACTORY_DEFAULT_SUMMARY=1` to measure the impact of adding `create_default` and observe the summary of hits and misses.

```sh
FACTORY_DEFAULT_SUMMARY=1 bin/rspec --tag slow:factory
```

--------------------------------

### Activating FactoryDoctor with Minitest CLI

Source: https://test-prof.evilmartians.io/llms-full.txt

Demonstrates how to activate FactoryDoctor for Minitest using the command-line option `--factory-doctor`.

```sh
ruby ... --factory-doctor
```

--------------------------------

### Minitest MemoryProf CLI Option

Source: https://test-prof.evilmartians.io/llms-full.txt

Run a specific Minitest file using the --mem-prof CLI option.

```sh
# Run a specific file using CLI option
ruby test/my_super_test.rb --mem-prof=rss
```

--------------------------------

### Collect SQL Queries with EventProf (RSpec)

Source: https://test-prof.evilmartians.io/llms-full.txt

Use the EVENT_PROF environment variable to collect SQL query statistics for every suite and example when running RSpec.

```sh
EVENT_PROF='sql.active_record' rspec ...
```

--------------------------------

### Configure BeforeAll Transaction Hooks

Source: https://test-prof.evilmartians.io/llms-full.txt

Register callbacks to execute before or after a transaction begins or is rolled back. Use the `configure` block to define these hooks.

```ruby
TestProf::BeforeAll.configure do |config|
  config.before(:begin) do
    # do something before transaction opens
  end
  # after(:begin) is also available

  config.after(:rollback) do
    # do something after transaction closes
  end
  # before(:rollback) is also available
end
```

--------------------------------

### Registering and Using Fixtures with DSL

Source: https://test-prof.evilmartians.io/llms-full.txt

Use the `fixture` method to register a fixture with a block that creates the record. It can also be used to fetch the registered fixture.

```ruby
before(:all) { fixture(:account) { create(:account) } }

let(:account) { fixture(:account) }
```

--------------------------------

### Modifying objects in before_all

Source: https://test-prof.evilmartians.io/llms-full.txt

When objects created in `before_all` are modified in tests, their state can become dependent on the test order. Reloading the record for every example can solve this.

```ruby
before_all do
  @user = create(:user)
end

let(:user) { @user }

it "when user is admin" do
  # we modified our object in-place!
  user.update!(role: 1)
  expect(user).to be_admin
end

it "when user is regular" do
  # now @user's state depends on the order of specs!
  expect(user).not_to be_admin
end
```

```ruby
before_all do
  @user = create(:user)
end

# Note, that @user.reload may not be enough,
# 'cause it doesn't reset associations
let(:user) { User.find(@user.id) }
```

```ruby
# or with Minitest
def setup
  @user = User.find(@user.id)
end
```

--------------------------------

### Bad Practice: Unnecessary Database Creation

Source: https://test-prof.evilmartians.io/llms-full.txt

Demonstrates an inefficient test pattern using `create` which performs database operations and callbacks when only validation is needed.

```ruby
# with FactoryBot/FactoryGirl
it "validates name presence" do
  user = create(:user)
  user.name = ""
  expect(user).not_to be_valid
end

# with Fabrication
it "validates name presence" do
  user = Fabricate(:user)
  user.name = ""
  expect(user).not_to be_valid
end
```

--------------------------------

### Disable 'let' Stats in RSpecDissect

Source: https://test-prof.evilmartians.io/llms-full.txt

To disable the collection and display of `let` statistics, configure `TestProf::RSpecDissect` within your RSpec setup to set `let_stats_enabled` to `false`.

```ruby
TestProf::RSpecDissect.configure do |config|
  config.let_stats_enabled = false
end

```

--------------------------------

### Run Minitest with EventProf CLI Option

Source: https://test-prof.evilmartians.io/llms-full.txt

Alternatively, you can use CLI options with Minitest to activate EventProf. This allows specifying the event to profile directly when running tests.

```sh
# Run a specific file using CLI option
ruby test/my_super_test.rb --event-prof=sql.active_record
```

--------------------------------

### Enable Per-Example Logging with RSpec Tag

Source: https://test-prof.evilmartians.io/llms-full.txt

Activate verbose logging for a specific RSpec example or group by adding the ':log' tag. This is useful for debugging individual tests.

```ruby
# Add the tag and you will see a lot of interesting stuff in your console
it "does smthng weird", :log do
  # ...
end

# or for the group
describe "GET #index", :log do
  # ...
end
```

--------------------------------

### Integrate RSpecDissect with RSpecStamp

Source: https://test-prof.evilmartians.io/llms-full.txt

Combine RSpecDissect with RSpecStamp to automatically tag slow example groups. Set `RD_PROF_STAMP` to a desired tag name to mark the slowest groups.

```sh
RD_PROF=1 RD_PROF_STAMP="slow" rspec ...
```

--------------------------------

### Require FactoryAllStub in RSpec

Source: https://test-prof.evilmartians.io/llms-full.txt

Include this line in your `spec_helper.rb` or `rails_helper.rb` to automatically initialize FactoryAllStub and enable the `factory: :stub` shared context.

```ruby
require "test_prof/recipes/rspec/factory_all_stub"

```

--------------------------------

### Activate EventProf with RSpec

Source: https://test-prof.evilmartians.io/llms-full.txt

To activate EventProf for RSpec, set the `EVENT_PROF` environment variable to the desired event name. This will collect statistics for all suites and examples related to that event.

```sh
# Collect SQL queries stats for every suite and example
EVENT_PROF='sql.active_record' rspec ...
```