Faker Ruby Library

The Faker::Markdown module (available since version 1.8.0) generates various markdown-formatted strings using Lorem Ipsum text. It can produce headers, lists, code blocks, tables, and complex text structures.

# Example of generating a random header
Faker::Markdown.headers

The Faker::HTML module (available since version 3.2.1) provides various methods to generate random HTML snippets, ranging from simple tags to complex structures like tables and lists.

# Example of using the module
Faker::HTML.heading
Faker::HTML.paragraph

By default, Faker does not guarantee unique values. To ensure a generator returns a value that hasn't been used in the current session, prefix the method call with .unique.

Note: If you exhaust the pool of available unique values for a specific generator, Faker will raise a Faker::UniqueGenerator::RetryLimitExceeded exception.

To prevent collisions or reset the uniqueness tracker (e.g., between test runs), you can clear the used values:

• Faker::Name.unique.clear: Clears used values for a specific generator.
• Faker::UniqueGenerator.clear: Clears used values for all generators.

# Return a unique name every time
Faker::Name.unique.name

# Clear used values for Faker::Name
Faker::Name.unique.clear

# Clear used values for all generators
Faker::UniqueGenerator.clear

Each generator implementation contains a @faker.version tag in its source code. You can use this tag to determine the minimum version of the Faker gem required to access that specific method or class. This is useful for debugging compatibility issues or determining if you need to update your gem version.

# Example of how a version tag appears in the source code

# Faker::TvShows::ParksAndRec.character

# @faker.version 1.9.0
def character
  fetch('parks_and_rec.characters')
end

In the faker-ruby/faker project, the English locale data is split across multiple files in the lib/locales/en/ directory to prevent a single en.yml file from becoming too large.

Each file in this directory corresponds to a specific Faker class. For example, the data used by Faker::Internet is stored in internet.yml within this directory.

Faker allows you to seed its pseudo-random number generator (PRNG) to produce the same sequence of data every time. This is useful for reproducible tests. You can set the seed by assigning a new Random object to Faker::Config.random.

# Set a seed for deterministic output
Faker::Config.random = Random.new(42)
Faker::Lorem.word              #=> "velit"
Faker::Lorem.word              #=> "quisquam"

# Re-seeding with the same value produces the same sequence
Faker::Config.random = Random.new(42)
Faker::Lorem.word              #=> "velit"

# Reset to default entropy sources
Faker::Config.random = nil

The Faker::IdNumber.valid and Faker::IdNumber.invalid methods are locale-aware. By setting Faker::Config.locale, these generic methods will return valid or invalid identification numbers specific to that region.

For example, setting the locale to en-GB will cause .valid to return a British National Insurance number.

Faker::Config.locale = 'fr-FR'
Faker::IdNumber.valid #=> "22510589696868"

Use the Faker::Games::WorldOfWarcraft module to generate randomized data related to the World of Warcraft universe, including hero names, character classes, races, and quotes.

# Generate a random character from World of Warcraft
Faker::Games::WorldOfWarcraft.hero #=> "Uther the Lightbringer"

# Generate a random class name from World of Warcraft
Faker::Games::WorldOfWarcraft.class_name #=> "Druid"

# Generate a random race from World of Warcraft
Faker::Games::WorldOfWarcraft.race #=> "Night elf"

# Generate a random quote from World of Warcraft
Faker::Games::WorldOfWarcraft.quote #=> "These are dark times indeed."

Use the Faker::Movies::HarryPotter module to generate random data related to the Harry Potter franchise, including characters, locations, quotes, books, houses, and spells. This module has been available since version 1.7.3.

Faker::Movies::HarryPotter.character #=> "Harry Potter"
Faker::Movies::HarryPotter.location #=> "Hogwarts"
Faker::Movies::HarryPotter.quote #=> "I solemnly swear that I am up to no good."
Faker::Movies::HarryPotter.book #=> "Harry Potter and the Chamber of Secrets"
Faker::Movies::HarryPotter.house #=> "Gryffindor"
Faker::Movies::HarryPotter.spell #=> "Reparo"

The Faker::TvShows::Simpsons module allows you to generate random data related to The Simpsons TV show, including characters, locations, and quotes. This module has been available since version 1.8.0.

Faker::TvShows::Simpsons.character #=> "Charles Montgomery Burns"

Faker::TvShows::Simpsons.location  #=> "Moe's Tavern"

Faker::TvShows::Simpsons.quote     #=> "It takes two to lie: one to lie and one to listen."