Merge pull request #28272 from rails/add-iso8601-and-rfc3339-parsing

Add iso8601 and rfc3339 parsing to timezones

8 files changed, 398 insertions, 0 deletions

diff --git a/activesupport/CHANGELOG.md b/activesupport/CHANGELOG.md
index 6ca227f40a..58956ad0e8 100644
--- a/activesupport/CHANGELOG.md
+++ b/activesupport/CHANGELOG.md
@@ -1,3 +1,81 @@
+*   Add `rfc3339` aliases to `xmlschema` for `Time` and `ActiveSupport::TimeWithZone`
+
+    For naming consistency when using the RFC 3339 profile of ISO 8601 in applications.
+
+    *Andrew White*
+
+*   Add `Time.rfc3339` parsing method
+
+    The `Time.xmlschema` and consequently its alias `iso8601` accepts timestamps
+    without a offset in contravention of the RFC 3339 standard. This method
+    enforces that constraint and raises an `ArgumentError` if it doesn't.
+
+    *Andrew White*
+
+*   Add `ActiveSupport::TimeZone.rfc3339` parsing method
+
+    Previously there was no way to get a RFC 3339 timestamp into a specific
+    timezone without either using `parse` or chaining methods. The new method
+    allows parsing directly into the timezone, e.g:
+
+        >> Time.zone = "Hawaii"
+        => "Hawaii"
+        >> Time.zone.rfc3339("1999-12-31T14:00:00Z")
+        => Fri, 31 Dec 1999 14:00:00 HST -10:00
+
+    This new method has stricter semantics than the current `parse` method
+    and will raise an `ArgumentError` instead of returning nil, e.g:
+
+        >> Time.zone = "Hawaii"
+        => "Hawaii"
+        >> Time.zone.rfc3339("foobar")
+        ArgumentError: invalid date
+        >> Time.zone.parse("foobar")
+        => nil
+
+    It will also raise an `ArgumentError` when either the time or offset
+    components are missing, e.g:
+
+        >> Time.zone = "Hawaii"
+        => "Hawaii"
+        >> Time.zone.rfc3339("1999-12-31")
+        ArgumentError: invalid date
+        >> Time.zone.rfc3339("1999-12-31T14:00:00")
+        ArgumentError: invalid date
+
+    *Andrew White*
+
+*   Add `ActiveSupport::TimeZone.iso8601` parsing method
+
+    Previously there was no way to get a ISO 8601 timestamp into a specific
+    timezone without either using `parse` or chaining methods. The new method
+    allows parsing directly into the timezone, e.g:
+
+        >> Time.zone = "Hawaii"
+        => "Hawaii"
+        >> Time.zone.iso8601("1999-12-31T14:00:00Z")
+        => Fri, 31 Dec 1999 14:00:00 HST -10:00
+
+    If the timestamp is a ISO 8601 date (YYYY-MM-DD) then the time is set
+    to midnight, e.g:
+
+        >> Time.zone = "Hawaii"
+        => "Hawaii"
+        >> Time.zone.iso8601("1999-12-31")
+        => Fri, 31 Dec 1999 00:00:00 HST -10:00
+
+    This new method has stricter semantics than the current `parse` method
+    and will raise an `ArgumentError` instead of returning nil, e.g:
+
+        >> Time.zone = "Hawaii"
+        => "Hawaii"
+        >> Time.zone.iso8601("foobar")
+        ArgumentError: invalid date
+        >> Time.zone.parse("foobar")
+        => nil
+
+    *Andrew White*
+
 *   Deprecate implicit coercion of `ActiveSupport::Duration`
 
     Currently `ActiveSupport::Duration` implicitly converts to a seconds
diff --git a/activesupport/lib/active_support/core_ext/time/calculations.rb b/activesupport/lib/active_support/core_ext/time/calculations.rb
index cbdcb86d6d..7b7aeef25a 100644
--- a/activesupport/lib/active_support/core_ext/time/calculations.rb
+++ b/activesupport/lib/active_support/core_ext/time/calculations.rb
@@ -53,6 +53,29 @@ class Time
     end
     alias_method :at_without_coercion, :at
     alias_method :at, :at_with_coercion
+
+    # Creates a +Time+ instance from an RFC 3339 string.
+    #
+    #   Time.rfc3339('1999-12-31T14:00:00-10:00') # => 2000-01-01 00:00:00 -1000
+    #
+    # If the time or offset components are missing then an +ArgumentError+ will be raised.
+    #
+    #   Time.rfc3339('1999-12-31') # => ArgumentError: invalid date
+    def rfc3339(str)
+      parts = Date._rfc3339(str)
+
+      raise ArgumentError, "invalid date" if parts.empty?
+
+      Time.new(
+        parts.fetch(:year),
+        parts.fetch(:mon),
+        parts.fetch(:mday),
+        parts.fetch(:hour),
+        parts.fetch(:min),
+        parts.fetch(:sec) + parts.fetch(:sec_fraction, 0),
+        parts.fetch(:offset)
+      )
+    end
   end
 
   # Returns the number of seconds since 00:00:00.
diff --git a/activesupport/lib/active_support/core_ext/time/conversions.rb b/activesupport/lib/active_support/core_ext/time/conversions.rb
index f2bbe55aa6..595bda6b4f 100644
--- a/activesupport/lib/active_support/core_ext/time/conversions.rb
+++ b/activesupport/lib/active_support/core_ext/time/conversions.rb
@@ -64,4 +64,7 @@ class Time
   def formatted_offset(colon = true, alternate_utc_string = nil)
     utc? && alternate_utc_string || ActiveSupport::TimeZone.seconds_to_utc_offset(utc_offset, colon)
   end
+
+  # Aliased to +xmlschema+ for compatibility with +DateTime+
+  alias_method :rfc3339, :xmlschema
 end
diff --git a/activesupport/lib/active_support/time_with_zone.rb b/activesupport/lib/active_support/time_with_zone.rb
index 857cc1a664..e31983cf26 100644
--- a/activesupport/lib/active_support/time_with_zone.rb
+++ b/activesupport/lib/active_support/time_with_zone.rb
@@ -148,6 +148,7 @@ module ActiveSupport
       "#{time.strftime(PRECISIONS[fraction_digits.to_i])}#{formatted_offset(true, 'Z'.freeze)}"
     end
     alias_method :iso8601, :xmlschema
+    alias_method :rfc3339, :xmlschema
 
     # Coerces time to a string for JSON encoding. The default format is ISO 8601.
     # You can get %Y/%m/%d %H:%M:%S +offset style by setting
diff --git a/activesupport/lib/active_support/values/time_zone.rb b/activesupport/lib/active_support/values/time_zone.rb
index 09cb9cbbe1..18477b9f6b 100644
--- a/activesupport/lib/active_support/values/time_zone.rb
+++ b/activesupport/lib/active_support/values/time_zone.rb
@@ -340,6 +340,41 @@ module ActiveSupport
     end
 
     # Method for creating new ActiveSupport::TimeWithZone instance in time zone
+    # of +self+ from an ISO 8601 string.
+    #
+    #   Time.zone = 'Hawaii'                     # => "Hawaii"
+    #   Time.zone.iso8601('1999-12-31T14:00:00') # => Fri, 31 Dec 1999 14:00:00 HST -10:00
+    #
+    # If the time components are missing then they will be set to zero.
+    #
+    #   Time.zone = 'Hawaii'            # => "Hawaii"
+    #   Time.zone.iso8601('1999-12-31') # => Fri, 31 Dec 1999 00:00:00 HST -10:00
+    #
+    # If the string is invalid then an +ArgumentError+ will be raised unlike +parse+
+    # which returns +nil+ when given an invalid date string.
+    def iso8601(str)
+      parts = Date._iso8601(str)
+
+      raise ArgumentError, "invalid date" if parts.empty?
+
+      time = Time.new(
+        parts.fetch(:year),
+        parts.fetch(:mon),
+        parts.fetch(:mday),
+        parts.fetch(:hour, 0),
+        parts.fetch(:min, 0),
+        parts.fetch(:sec, 0) + parts.fetch(:sec_fraction, 0),
+        parts.fetch(:offset, 0)
+      )
+
+      if parts[:offset]
+        TimeWithZone.new(time.utc, self)
+      else
+        TimeWithZone.new(nil, self, time)
+      end
+    end
+
+    # Method for creating new ActiveSupport::TimeWithZone instance in time zone
     # of +self+ from parsed string.
     #
     #   Time.zone = 'Hawaii'                   # => "Hawaii"
@@ -359,6 +394,36 @@ module ActiveSupport
       parts_to_time(Date._parse(str, false), now)
     end
 
+    # Method for creating new ActiveSupport::TimeWithZone instance in time zone
+    # of +self+ from an RFC 3339 string.
+    #
+    #   Time.zone = 'Hawaii'                     # => "Hawaii"
+    #   Time.zone.rfc3339('2000-01-01T00:00:00Z') # => Fri, 31 Dec 1999 14:00:00 HST -10:00
+    #
+    # If the time or zone components are missing then an +ArgumentError+ will
+    # be raised. This is much stricter than either +parse+ or +iso8601+ which
+    # allow for missing components.
+    #
+    #   Time.zone = 'Hawaii'            # => "Hawaii"
+    #   Time.zone.rfc3339('1999-12-31') # => ArgumentError: invalid date
+    def rfc3339(str)
+      parts = Date._rfc3339(str)
+
+      raise ArgumentError, "invalid date" if parts.empty?
+
+      time = Time.new(
+        parts.fetch(:year),
+        parts.fetch(:mon),
+        parts.fetch(:mday),
+        parts.fetch(:hour),
+        parts.fetch(:min),
+        parts.fetch(:sec) + parts.fetch(:sec_fraction, 0),
+        parts.fetch(:offset)
+      )
+
+      TimeWithZone.new(time.utc, self)
+    end
+
     # Parses +str+ according to +format+ and returns an ActiveSupport::TimeWithZone.
     #
     # Assumes that +str+ is a time in the time zone +self+,
diff --git a/activesupport/test/core_ext/time_ext_test.rb b/activesupport/test/core_ext/time_ext_test.rb
index a399e36dc9..bd644c8457 100644
--- a/activesupport/test/core_ext/time_ext_test.rb
+++ b/activesupport/test/core_ext/time_ext_test.rb
@@ -569,6 +569,11 @@ class TimeExtCalculationsTest < ActiveSupport::TestCase
     Time::DATE_FORMATS.delete(:custom)
   end
 
+  def test_rfc3339_with_fractional_seconds
+    time = Time.new(1999, 12, 31, 19, 0, Rational(1, 8), -18000)
+    assert_equal "1999-12-31T19:00:00.125-05:00", time.rfc3339(3)
+  end
+
   def test_to_date
     assert_equal Date.new(2005, 2, 21), Time.local(2005, 2, 21, 17, 44, 30).to_date
   end
@@ -910,6 +915,37 @@ class TimeExtCalculationsTest < ActiveSupport::TestCase
   def test_all_year
     assert_equal Time.local(2011, 1, 1, 0, 0, 0)..Time.local(2011, 12, 31, 23, 59, 59, Rational(999999999, 1000)), Time.local(2011, 6, 7, 10, 10, 10).all_year
   end
+
+  def test_rfc3339_parse
+    time = Time.rfc3339("1999-12-31T19:00:00.125-05:00")
+
+    assert_equal 1999, time.year
+    assert_equal 12, time.month
+    assert_equal 31, time.day
+    assert_equal 19, time.hour
+    assert_equal 0, time.min
+    assert_equal 0, time.sec
+    assert_equal 125000, time.usec
+    assert_equal(-18000, time.utc_offset)
+
+    exception = assert_raises(ArgumentError) do
+      Time.rfc3339("1999-12-31")
+    end
+
+    assert_equal "invalid date", exception.message
+
+    exception = assert_raises(ArgumentError) do
+      Time.rfc3339("1999-12-31T19:00:00")
+    end
+
+    assert_equal "invalid date", exception.message
+
+    exception = assert_raises(ArgumentError) do
+      Time.rfc3339("foobar")
+    end
+
+    assert_equal "invalid date", exception.message
+  end
 end
 
 class TimeExtMarshalingTest < ActiveSupport::TestCase
diff --git a/activesupport/test/core_ext/time_with_zone_test.rb b/activesupport/test/core_ext/time_with_zone_test.rb
index 1534daacb9..3cc29ca040 100644
--- a/activesupport/test/core_ext/time_with_zone_test.rb
+++ b/activesupport/test/core_ext/time_with_zone_test.rb
@@ -144,6 +144,16 @@ class TimeWithZoneTest < ActiveSupport::TestCase
     assert_equal "1999-12-31T19:00:00-05:00", @twz.xmlschema(nil)
   end
 
+  def test_iso8601_with_fractional_seconds
+    @twz += Rational(1, 8)
+    assert_equal "1999-12-31T19:00:00.125-05:00", @twz.iso8601(3)
+  end
+
+  def test_rfc3339_with_fractional_seconds
+    @twz += Rational(1, 8)
+    assert_equal "1999-12-31T19:00:00.125-05:00", @twz.rfc3339(3)
+  end
+
   def test_to_yaml
     yaml = <<-EOF.strip_heredoc
       --- !ruby/object:ActiveSupport::TimeWithZone
diff --git a/activesupport/test/time_zone_test.rb b/activesupport/test/time_zone_test.rb
index 4794b55742..1615d8fdb2 100644
--- a/activesupport/test/time_zone_test.rb
+++ b/activesupport/test/time_zone_test.rb
@@ -215,6 +215,95 @@ class TimeZoneTest < ActiveSupport::TestCase
     assert_equal secs, twz.to_f
   end
 
+  def test_iso8601
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+    twz = zone.iso8601("1999-12-31T19:00:00")
+    assert_equal Time.utc(1999, 12, 31, 19), twz.time
+    assert_equal Time.utc(2000), twz.utc
+    assert_equal zone, twz.time_zone
+  end
+
+  def test_iso8601_with_fractional_seconds
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+    twz = zone.iso8601("1999-12-31T19:00:00.750")
+    assert_equal 750000, twz.time.usec
+    assert_equal Time.utc(1999, 12, 31, 19, 0, 0 + Rational(3, 4)), twz.time
+    assert_equal Time.utc(2000, 1, 1, 0, 0, 0 + Rational(3, 4)), twz.utc
+    assert_equal zone, twz.time_zone
+  end
+
+  def test_iso8601_with_zone
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+    twz = zone.iso8601("1999-12-31T14:00:00-10:00")
+    assert_equal Time.utc(1999, 12, 31, 19), twz.time
+    assert_equal Time.utc(2000), twz.utc
+    assert_equal zone, twz.time_zone
+  end
+
+  def test_iso8601_with_invalid_string
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+
+    exception = assert_raises(ArgumentError) do
+      zone.iso8601("foobar")
+    end
+
+    assert_equal "invalid date", exception.message
+  end
+
+  def test_iso8601_with_missing_time_components
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+    twz = zone.iso8601("1999-12-31")
+    assert_equal Time.utc(1999, 12, 31, 0, 0, 0), twz.time
+    assert_equal Time.utc(1999, 12, 31, 5, 0, 0), twz.utc
+    assert_equal zone, twz.time_zone
+  end
+
+  def test_iso8601_with_old_date
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+    twz = zone.iso8601("1883-12-31T19:00:00")
+    assert_equal [0, 0, 19, 31, 12, 1883], twz.to_a[0, 6]
+    assert_equal zone, twz.time_zone
+  end
+
+  def test_iso8601_far_future_date_with_time_zone_offset_in_string
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+    twz = zone.iso8601("2050-12-31T19:00:00-10:00") # i.e., 2050-01-01 05:00:00 UTC
+    assert_equal [0, 0, 0, 1, 1, 2051], twz.to_a[0, 6]
+    assert_equal zone, twz.time_zone
+  end
+
+  def test_iso8601_should_not_black_out_system_timezone_dst_jump
+    with_env_tz("EET") do
+      zone = ActiveSupport::TimeZone["Pacific Time (US & Canada)"]
+      twz = zone.iso8601("2012-03-25T03:29:00")
+      assert_equal [0, 29, 3, 25, 3, 2012], twz.to_a[0, 6]
+    end
+  end
+
+  def test_iso8601_should_black_out_app_timezone_dst_jump
+    with_env_tz("EET") do
+      zone = ActiveSupport::TimeZone["Pacific Time (US & Canada)"]
+      twz = zone.iso8601("2012-03-11T02:29:00")
+      assert_equal [0, 29, 3, 11, 3, 2012], twz.to_a[0, 6]
+    end
+  end
+
+  def test_iso8601_doesnt_use_local_dst
+    with_env_tz "US/Eastern" do
+      zone = ActiveSupport::TimeZone["UTC"]
+      twz = zone.iso8601("2013-03-10T02:00:00")
+      assert_equal Time.utc(2013, 3, 10, 2, 0, 0), twz.time
+    end
+  end
+
+  def test_iso8601_handles_dst_jump
+    with_env_tz "US/Eastern" do
+      zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+      twz = zone.iso8601("2013-03-10T02:00:00")
+      assert_equal Time.utc(2013, 3, 10, 3, 0, 0), twz.time
+    end
+  end
+
   def test_parse
     zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
     twz = zone.parse("1999-12-31 19:00:00")
@@ -314,6 +403,99 @@ class TimeZoneTest < ActiveSupport::TestCase
     end
   end
 
+  def test_rfc3339
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+    twz = zone.rfc3339("1999-12-31T14:00:00-10:00")
+    assert_equal Time.utc(1999, 12, 31, 19), twz.time
+    assert_equal Time.utc(2000), twz.utc
+    assert_equal zone, twz.time_zone
+  end
+
+  def test_rfc3339_with_fractional_seconds
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+    twz = zone.iso8601("1999-12-31T14:00:00.750-10:00")
+    assert_equal 750000, twz.time.usec
+    assert_equal Time.utc(1999, 12, 31, 19, 0, 0 + Rational(3, 4)), twz.time
+    assert_equal Time.utc(2000, 1, 1, 0, 0, 0 + Rational(3, 4)), twz.utc
+    assert_equal zone, twz.time_zone
+  end
+
+  def test_rfc3339_with_missing_time
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+
+    exception = assert_raises(ArgumentError) do
+      zone.rfc3339("1999-12-31")
+    end
+
+    assert_equal "invalid date", exception.message
+  end
+
+  def test_rfc3339_with_missing_offset
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+
+    exception = assert_raises(ArgumentError) do
+      zone.rfc3339("1999-12-31T19:00:00")
+    end
+
+    assert_equal "invalid date", exception.message
+  end
+
+  def test_rfc3339_with_invalid_string
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+
+    exception = assert_raises(ArgumentError) do
+      zone.rfc3339("foobar")
+    end
+
+    assert_equal "invalid date", exception.message
+  end
+
+  def test_rfc3339_with_old_date
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+    twz = zone.rfc3339("1883-12-31T19:00:00-05:00")
+    assert_equal [0, 0, 19, 31, 12, 1883], twz.to_a[0, 6]
+    assert_equal zone, twz.time_zone
+  end
+
+  def test_rfc3339_far_future_date_with_time_zone_offset_in_string
+    zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+    twz = zone.rfc3339("2050-12-31T19:00:00-10:00") # i.e., 2050-01-01 05:00:00 UTC
+    assert_equal [0, 0, 0, 1, 1, 2051], twz.to_a[0, 6]
+    assert_equal zone, twz.time_zone
+  end
+
+  def test_rfc3339_should_not_black_out_system_timezone_dst_jump
+    with_env_tz("EET") do
+      zone = ActiveSupport::TimeZone["Pacific Time (US & Canada)"]
+      twz = zone.rfc3339("2012-03-25T03:29:00-07:00")
+      assert_equal [0, 29, 3, 25, 3, 2012], twz.to_a[0, 6]
+    end
+  end
+
+  def test_rfc3339_should_black_out_app_timezone_dst_jump
+    with_env_tz("EET") do
+      zone = ActiveSupport::TimeZone["Pacific Time (US & Canada)"]
+      twz = zone.rfc3339("2012-03-11T02:29:00-08:00")
+      assert_equal [0, 29, 3, 11, 3, 2012], twz.to_a[0, 6]
+    end
+  end
+
+  def test_rfc3339_doesnt_use_local_dst
+    with_env_tz "US/Eastern" do
+      zone = ActiveSupport::TimeZone["UTC"]
+      twz = zone.rfc3339("2013-03-10T02:00:00Z")
+      assert_equal Time.utc(2013, 3, 10, 2, 0, 0), twz.time
+    end
+  end
+
+  def test_rfc3339_handles_dst_jump
+    with_env_tz "US/Eastern" do
+      zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
+      twz = zone.iso8601("2013-03-10T02:00:00-05:00")
+      assert_equal Time.utc(2013, 3, 10, 3, 0, 0), twz.time
+    end
+  end
+
   def test_strptime
     zone = ActiveSupport::TimeZone["Eastern Time (US & Canada)"]
     twz = zone.strptime("1999-12-31 12:00:00", "%Y-%m-%d %H:%M:%S")