Dates which can be used to check date handling code.
The JSON file dates.json contains several lists of dates:
- examples: examples of dates with particular properties, such as being the last day of the month, being a leap day, etc.
- valid: valid dates from the Gregorian calendar, years 1 through 9999. Unlike 'examples', these dates often have a special significance, for example the first day of the Unix epoch. Some of these dates might be recognized as invalid by date handling code with specific bugs.
- extra: valid Gregorian dates which are not from years 1-9999. Some date code cannot work with these, nevertheless they are correct dates.
- invalid: things which aren't valid dates in the Gregorian calendar, and should be recognized as invalid.
The format of a date object is a follows:
- year: an integer.
- month: an integer 1-12.
- day: an integer 1-31.
- weekday: a weekday string such as "Tuesday". Not present for invalid dates.
- calendar: a string, always "Gregorian" except for "invalid" dates. "Gregorian" means the proleptic Gregorian calendar, ie the Gregorian calendar as extended backwards beyond the date of its actual invention.
- description: a short, unique string which describes the date.
- comment: a longer string which explains the date.