1 files changed, 36 insertions, 0 deletions
diff --git a/spec/ruby/library/date/valid_date_spec.rb b/spec/ruby/library/date/valid_date_spec.rb
new file mode 100644
index 0000000000..f0d5ec7b4d
--- /dev/null
+++ b/spec/ruby/library/date/valid_date_spec.rb
@@ -0,0 +1,36 @@
+require_relative '../../spec_helper'
+require 'date'
+
+describe "Date.valid_date?" do
+  # 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
+  it "returns true if it is a valid civil date" do
+    Date.valid_date?(1582, 10, 15).should == true
+    Date.valid_date?(1582, 10, 14, Date::ENGLAND).should == true
+  end
+
+  it "returns false if it is not a valid civil date" do
+    Date.valid_date?(1582, 10, 14).should == false
+  end
+
+  it "handles negative months and days" do
+    # October 1582 (the Gregorian calendar, Civil Date)
+    #     S   M  Tu   W  Th   F   S
+    #       -21 -20 -19 -18 -17 -16
+    #   -15 -14 -13 -12 -11 -10  -9
+    #    -8  -7  -6  -5  -4  -3  -2
+    #    -1
+    Date.valid_date?(1582, -3, -22).should == false
+    Date.valid_date?(1582, -3, -21).should == true
+    Date.valid_date?(1582, -3, -18).should == true
+    Date.valid_date?(1582, -3, -17).should == true
+
+    Date.valid_date?(2007, -11, -10).should == true
+    Date.valid_date?(2008, -11, -10).should == true
+  end
+end