1 files changed, 49 insertions, 0 deletions
diff --git a/spec/ruby/library/date/commercial_spec.rb b/spec/ruby/library/date/commercial_spec.rb
new file mode 100644
index 0000000000..8e2df79b90
--- /dev/null
+++ b/spec/ruby/library/date/commercial_spec.rb
@@ -0,0 +1,49 @@
+require 'date'
+require_relative '../../spec_helper'
+
+# reference:
+# October 1582 (the Gregorian calendar, Civil Date)
+#   S   M  Tu   W  Th   F   S
+#       1   2   3   4  15  16
+#  17  18  19  20  21  22  23
+#  24  25  26  27  28  29  30
+#  31
+describe "Date.commercial" do
+  it "creates a Date for Julian Day Number day 0 by default" do
+    d = Date.commercial
+    d.year.should == -4712
+    d.month.should == 1
+    d.day.should == 1
+  end
+
+  it "creates a Date for the monday in the year and week given" do
+    d = Date.commercial(2000, 1)
+    d.year.should == 2000
+    d.month.should == 1
+    d.day.should == 3
+    d.cwday.should == 1
+  end
+
+  it "creates a Date for the correct day given the year, week and day number" do
+    d = Date.commercial(2004, 1, 1)
+    d.year.should == 2003
+    d.month.should == 12
+    d.day.should == 29
+    d.cwday.should == 1
+    d.cweek.should == 1
+    d.cwyear.should == 2004
+  end
+
+  it "creates only Date objects for valid weeks" do
+    -> { Date.commercial(2004, 53, 1) }.should_not.raise(ArgumentError)
+    -> { Date.commercial(2004, 53, 0) }.should.raise(ArgumentError)
+    -> { Date.commercial(2004, 53, 8) }.should.raise(ArgumentError)
+    -> { Date.commercial(2004, 54, 1) }.should.raise(ArgumentError)
+    -> { Date.commercial(2004,  0, 1) }.should.raise(ArgumentError)
+
+    -> { Date.commercial(2003, 52, 1) }.should_not.raise(ArgumentError)
+    -> { Date.commercial(2003, 53, 1) }.should.raise(ArgumentError)
+    -> { Date.commercial(2003, 52, 0) }.should.raise(ArgumentError)
+    -> { Date.commercial(2003, 52, 8) }.should.raise(ArgumentError)
+  end
+end