Fix leap years

closes #13
hzamani · Nov 30, 2022 · 78600db · 78600db
1 parent e23cdb4
commit 78600db
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Showing 2 changed files with 11 additions and 7 deletions.
diff --git a/lib/parsi-date.rb b/lib/parsi-date.rb
@@ -141,11 +141,13 @@ class Date
     LD_EPOCH_IN_CJD        = 2299160 # :nodoc:
     DAYS_IN_MONTH          = [nil, 31, 31, 31, 31, 31, 31, 30, 30, 30, 30, 30, 29] # :nodoc:
 
+    LEAP_REMINDERS         = [1, 5, 9, 13, 17, 22, 26, 30].freeze
+
     shared_methods = Module.new do
 
       # Returns true if the given year is a leap year of the calendar.
       def leap? year
-        ((((((year - ((year > 0) ? 474 : 473)) % 2820) + 474) + 38) * 682) % 2816) < 682
+        LEAP_REMINDERS.include?(year - (year / 33).floor * 33)
       end
       alias_method :jalali_leap?, :leap?
 

diff --git a/spec/parsi-date/leap_spec.rb b/spec/parsi-date/leap_spec.rb
@@ -1,13 +1,15 @@
 describe "Parsi::Date#leap?" do
   it "returns true if a year is a leap year in the Parsi (Jalali) calendar" do
-    expect(Parsi::Date.leap?(1387)).to be_truthy
-    expect(Parsi::Date.leap?(1391)).to be_truthy
-    expect(Parsi::Date.leap?(1395)).to be_truthy
+    expect Parsi::Date.leap?(1387) == true
+    expect Parsi::Date.leap?(1391) == true
+    expect Parsi::Date.leap?(1395) == true
+    expect Parsi::Date.leap?(1403) == true
   end
 
   it "returns false if a year is not a leap year in the Parsi (Jalali) calendar" do
-    expect(Parsi::Date.leap?(1390)).to be_falsey
-    expect(Parsi::Date.leap?(1392)).to be_falsey
-    expect(Parsi::Date.leap?(1400)).to be_falsey
+    expect Parsi::Date.leap?(1390) == false
+    expect Parsi::Date.leap?(1392) == false
+    expect Parsi::Date.leap?(1400) == false
+    expect Parsi::Date.leap?(1404) == false
   end
 end