Extracting Date, Time and Datetime from ruby-hl7

The methods "to_hl7" used to be on ruby-hl7 file.
Also, did some refactoring for reducing
the code duplication.   Before that, I've added
some test.

Author: mogox

Gemfile

@@ -8,4 +8,5 @@ gem 'technicalpickles-jeweler'
 group :test, :development do
   gem 'rcov'
   gem 'rspec', '< 2.0.0'
+  gem 'debugger'
 end

Gemfile.lock

@@ -2,6 +2,14 @@ GEM
   remote: http://gems.github.com/
   remote: http://rubygems.org/
   specs:
+    columnize (0.3.6)
+    debugger (1.3.0)
+      columnize (>= 0.3.1)
+      debugger-linecache (~> 1.1.1)
+      debugger-ruby_core_source (~> 1.1.7)
+    debugger-linecache (1.1.2)
+      debugger-ruby_core_source (>= 1.1.1)
+    debugger-ruby_core_source (1.1.7)
     git (1.2.5)
     json_pure (1.5.0)
     rake (0.8.7)
@@ -17,6 +25,7 @@ PLATFORMS
   ruby
 
 DEPENDENCIES
+  debugger
   rake
   rcov
   rspec (< 2.0.0)

lib/core_ext/date_time.rb

@@ -0,0 +1,49 @@
+module HL7Time
+  # Get a HL7 timestamp (type TS) for a Time instance.
+  #
+  # fraction_digits:: specifies a number of digits of fractional seconds.
+  #                   Its default value is 0.
+  #
+  #  Time.parse('01:23').to_hl7
+  #  => "20091202012300"
+  #  Time.now.to_hl7(3)
+  #  => "20091202153652.302"
+  def to_hl7( fraction_digits = 0)
+    strftime('%Y%m%d%H%M%S') + hl7_fractions(fraction_digits)
+  end
+
+private
+  def hl7_fractions(fraction_digits = 0)
+    return '' unless fraction_digits > 0
+    time_fraction =  hl7_time_fraction
+    answer = '.' + sprintf('%06d', time_fraction) + '0' * ((fraction_digits - 6)).abs
+    answer[0, 1 + fraction_digits]
+  end
+
+  def hl7_time_fraction
+    if respond_to? :usec
+      usec
+    else
+      sec_fraction.to_f * 1000000
+    end
+  end
+end
+
+class Date
+  # Get a HL7 timestamp (type TS) for a Date instance.
+  #
+  #  Date.parse('2009-12-02').to_hl7
+  #  => "20091202"
+  def to_hl7
+    strftime('%Y%m%d')
+  end
+end
+
+class Time
+  include HL7Time
+end
+
+class DateTime
+  include HL7Time
+end
+

lib/string.rb lib/core_ext/string.rblib/string.rb renamed to lib/core_ext/string.rb

@@ -677,58 +677,6 @@ def write_field( name, value ) #:nodoc:
 
 end
 
-class Date
-  # Get a HL7 timestamp (type TS) for a Date instance.
-  #
-  #  Date.parse('2009-12-02').to_hl7
-  #  => "20091202"
-  def to_hl7
-    strftime('%Y%m%d')
-  end
-end
-
-class Time
-  # Get a HL7 timestamp (type TS) for a Time instance.
-  #
-  # fraction_digits:: specifies a number of digits of fractional seconds. Its default value is 0.
-  #
-  #  Time.parse('01:23').to_hl7
-  #  => "20091202012300"
-  #  Time.now.to_hl7(3)
-  #  => "20091202153652.302"
-  def to_hl7( fraction_digits = 0)
-    strftime('%Y%m%d%H%M%S') +
-      if fraction_digits == 0
-        ''
-      elsif fraction_digits <= 6
-        '.' + sprintf('%06d', usec)[0, fraction_digits]
-      else
-        '.' + sprintf('%06d', usec) + '0' * (fraction_digits - 6)
-      end
-  end
-end
-
-class DateTime
-  # Get a HL7 timestamp (type TS) for a Time instance.
-  #
-  # fraction_digits:: specifies a number of digits of fractional seconds. Its default value is 0.
-  #
-  #  Time.parse('01:23').to_hl7
-  #  => "20091202012300"
-  #  Time.now.to_hl7(3)
-  #  => "20091202153652.302"
-  def to_hl7( fraction_digits = 0)
-    strftime('%Y%m%d%H%M%S') +
-      if fraction_digits == 0
-        ''
-      elsif fraction_digits <= 6
-        '.' + sprintf('%06d', usec)[0, fraction_digits]
-      else
-        '.' + sprintf('%06d', usec) + '0' * (fraction_digits - 6)
-      end
-  end
-end
-
 # parse an hl7 formatted date
 #def Date.from_hl7( hl7_date )
 #end

lib/ruby-hl7.rb

@@ -0,0 +1,43 @@
+require File.expand_path('../../../lib/core_ext/date_time', __FILE__)
+
+describe Date do
+
+ 	subject{ Date.parse('2013-12-02').to_hl7 }
+
+  it "should respond to the HL7 timestamp" do
+  	subject.should eq "20131202"
+  end
+end
+
+describe "to_hl7 for time related classes" do
+
+  let(:formated_time){ time_now.strftime('%Y%m%d%H%M%S') }
+  let(:fraction_3){ "." + sprintf('%06d', time_now.to_time.usec)[0, 3] }
+  let(:fraction_9){ "." + sprintf('%06d', time_now.to_time.usec) + ("0" * 3) }
+
+  shared_examples "a time to_hl7" do
+    context "without fraction" do
+      it { time_now.to_time.to_hl7.should eq formated_time }
+    end
+
+    context "with_fraction" do
+      it { time_now.to_time.to_hl7(3).should eq formated_time + fraction_3 }
+
+      it { time_now.to_time.to_hl7(9).should eq formated_time + fraction_9 }
+    end
+  end
+
+  describe Time do
+    let(:time_now){ Time.now }
+
+    it_should_behave_like "a time to_hl7"
+  end
+
+  describe DateTime do
+    let(:time_now){ DateTime.now }
+
+    it_should_behave_like "a time to_hl7"
+  end
+
+end
+