SmarterDates

Natural-language date and datetime attribute parsing for Ruby and Rails.

Date/datetime attributes ending in _d, _on, _dt, or _at are parsed from human-friendly strings ("yesterday", "noon march 15") into proper Date or DateTime values. Works with ActiveRecord, plain Ruby objects, ActiveModel attributes, or as a standalone parser.

gem "smarter_dates"

The suffix on the attribute name decides what type is produced:

class Activity < ActiveRecord::Base
  include SmarterDates::ActiveRecordIntegration
end

a = Activity.new
a.birth_d = "22 April 1976"  # => stored as Date
a.meeting_dt = "next friday at noon"  # => stored as DateTime
a.created_on = "one week ago"
a.updated_at = "yesterday"

The legacy mixin still works:

class Activity < ActiveRecord::Base
  include SmarterDates  # auto-detects AR base class
end

class Reminder
  attr_accessor :due_on, :remind_at
  include SmarterDates::PlainIntegration
end

r = Reminder.new
r.due_on = "next monday"
r.remind_at = "in 30 minutes"

class Draft
  include ActiveModel::Attributes
  attribute :start_on, :chronic_date
  attribute :remind_at, :chronic_datetime
end

With Rails, :chronic_date and :chronic_datetime register automatically via the Railtie.

class Activity < ActiveRecord::Base
  validates :birth_d, chronic_parsable: true
  validates :meeting_dt, chronic_parsable: { datetime: true }
end

SmarterDates::Parser.to_date("yesterday")        # => #<Date: 2026-05-24>
SmarterDates::Parser.to_datetime("in 2 hours")   # => #<DateTime: ...>
SmarterDates::Parser.parsable?("noon march 15")  # => true

Lexically scoped — no global monkey-patching.

require "smarter_dates/core_ext"
using SmarterDates::CoreExt

"yesterday".to_chronic_date
"noon march 15".to_chronic_datetime
"now".to_chronic_time

The parser tries Chronic.parse first (when gitlab-chronic or the original chronic gem is loaded), then falls back to DateTime.parse and Date.parse from the stdlib. Unparseable input returns nil.

gitlab-chronic is the actively-maintained Chronic fork. The original mojombo/chronic is unmaintained but remains API-compatible — both work as drop-in runtime dependencies.

• Ruby >= 3.2.0
• ActiveModel >= 7.2 (for the validator and custom types)
• ActiveRecord >= 7.2 (for the AR integration)

Tested matrix: Ruby 3.4 + 4.0 × ActiveRecord 7.2 + 8.1.

Version 1.0 is a clean rewrite. Breaking changes:

• String#to_chronic_* is no longer a global monkey-patch. Use using SmarterDates::CoreExt to opt in per-file.
• include SmarterDates still works, but routes through ActiveRecordIntegration or PlainIntegration.
• The Configuration.for("smarter_dates") install generator and initializer template were removed (the option was never wired to anything).
• Minimum Ruby is 3.2; minimum ActiveRecord is 7.2.

MIT — see LICENSE.