commit 1e683e236b0429823fdbcced528791bc33bcccc8
parent 67689bec48d2543fe209b956a594922358025883
Author: Vlad-Stefan Harbuz <vlad@vladh.net>
Date: Sun, 9 Jan 2022 12:50:56 +0100
add calc_epochal_from_yd()
Signed-off-by: Vlad-Stefan Harbuz <vlad@vladh.net>
Signed-off-by: Byron Torres <b@torresjrjr.com>
Diffstat:
| M | datetime/date.ha | | | 127 | ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++----- |
1 file changed, 120 insertions(+), 7 deletions(-)
diff --git a/datetime/date.ha b/datetime/date.ha
@@ -11,12 +11,6 @@ export def EPOCHAL_JULIAN: i64 = -2440588;
// The Hare epoch of the Gregorian Common Era
export def EPOCHAL_GREGORIAN: i64 = -719164;
-// Calculates whether a given (year, month, date) is valid
-export fn is_valid_ymd(y: int, m: int, d: int) bool = {
- return m >= 1 && m <= 12 && d >= 1 &&
- d <= calc_n_days_in_month(y, m);
-};
-
// Calculates whether a given year is a leap year.
export fn is_leap_year(y: int) bool = {
return if (y % 4 != 0) false
@@ -25,6 +19,17 @@ export fn is_leap_year(y: int) bool = {
else true;
};
+// Calculates whether a given (year, month, date) is valid
+fn is_valid_ymd(y: int, m: int, d: int) bool = {
+ return m >= 1 && m <= 12 && d >= 1 &&
+ d <= calc_n_days_in_month(y, m);
+};
+
+// Returns whether a (year, yearday) date is valid
+fn is_valid_yd(y: int, yd: int) bool = {
+ return yd >= 1 && yd <= calc_n_days_in_year(y);
+};
+
// Calculates the number of days in the given month of the given year
fn calc_n_days_in_month(y: int, m: int) int = {
const days_per_month: [_]int = [
@@ -213,9 +218,32 @@ fn calc_epochal_from_ywd(y: int, w: int, wd: int) (chrono::epochal | errors::inv
abort("TODO");
};
+// Calculates a (year, month, day) date given a (year, yearday) date
+fn calc_ymd_from_yd(y: int, yd: int) ((int, int, int) | errors::invalid) = {
+ if (!is_valid_yd(y, yd)) {
+ return errors::invalid;
+ };
+ let m: int = 1;
+ let monthdays = calc_n_days_in_month(y, m);
+ let d = yd;
+ for (true) {
+ if (m > 12) {
+ return errors::invalid;
+ };
+ if (d <= monthdays) {
+ return (y, m, d);
+ };
+ d -= monthdays;
+ m += 1;
+ monthdays = calc_n_days_in_month(y, m);
+ };
+ return errors::invalid;
+};
+
// Calculates the [[chrono::epochal]], given a (year, yearday) date
fn calc_epochal_from_yd(y: int, yd: int) (chrono::epochal | errors::invalid) = {
- abort("TODO");
+ const ymd = calc_ymd_from_yd(y, yd)?;
+ return calc_epochal_from_ymd(ymd.0, ymd.1, ymd.2)?;
};
@test fn calc_epochal_from_ymd() void = {
@@ -267,6 +295,91 @@ fn calc_epochal_from_yd(y: int, yd: int) (chrono::epochal | errors::invalid) = {
};
};
+@test fn calc_ymd_from_yd() void = {
+ const cases = [
+ ((-0768, 01, 01), 1),
+ ((-0768, 02, 05), 36),
+ ((-0001, 12, 31), 365),
+ (( 0000, 01, 01), 1),
+ (( 0000, 01, 02), 2),
+ (( 0000, 12, 31), 366),
+ (( 0001, 01, 01), 1),
+ (( 0001, 01, 02), 2),
+ (( 1965, 03, 23), 82),
+ (( 1969, 12, 31), 365),
+ (( 1970, 01, 01), 1),
+ (( 1970, 01, 02), 2),
+ (( 1999, 12, 31), 365),
+ (( 2000, 01, 01), 1),
+ (( 2000, 01, 02), 2),
+ (( 2020, 01, 01), 1),
+ (( 2022, 02, 28), 59),
+ (( 2022, 03, 01), 60),
+ (( 2023, 12, 31), 365),
+ (( 2024, 02, 28), 59),
+ (( 2024, 02, 29), 60),
+ (( 2024, 03, 01), 61),
+ (( 2024, 12, 12), 347),
+ (( 2024, 12, 31), 366),
+ (( 2038, 01, 18), 18),
+ (( 2038, 01, 19), 19),
+ (( 2038, 01, 20), 20),
+ (( 2243, 10, 17), 290),
+ (( 4707, 11, 28), 332),
+ (( 4707, 11, 29), 333),
+ ((29349, 01, 25), 25),
+ ];
+
+ for (let i = 0z; i < len(cases); i += 1) {
+ const expected = cases[i].0;
+ const yd = cases[i].1;
+ const actual = calc_ymd_from_yd(expected.0, yd)!;
+ assert(expected.0 == actual.0 &&
+ expected.1 == actual.1 &&
+ expected.2 == actual.2,
+ "incorrect calc_ymd_from_yd() result");
+ };
+};
+
+@test fn calc_epochal_from_yd() void = {
+ const cases = [
+ (-0768, 36, -999999),
+ (-0001, 365, -719529),
+ ( 0000, 1, -719528),
+ ( 0000, 2, -719527),
+ ( 0000, 366, -719163),
+ ( 0001, 1, -719162),
+ ( 0001, 2, -719161),
+ ( 1965, 82, -1745 ),
+ ( 1969, 365, -1 ),
+ ( 1970, 1, 0 ),
+ ( 1970, 2, 1 ),
+ ( 1999, 365, 10956 ),
+ ( 2000, 1, 10957 ),
+ ( 2000, 2, 10958 ),
+ ( 2038, 18, 24854 ),
+ ( 2038, 19, 24855 ),
+ ( 2038, 20, 24856 ),
+ ( 2243, 290, 100000 ),
+ ( 4707, 332, 999999 ),
+ ( 4707, 333, 1000000),
+ (29349, 25, 9999999),
+ ];
+
+ for (let i = 0z; i < len(cases); i += 1) {
+ const y = cases[i].0;
+ const yd = cases[i].1;
+ const expected = cases[i].2;
+ const actual = calc_epochal_from_yd(y, yd)!;
+ assert(expected == actual,
+ "error in epochal calculation from yd");
+ };
+ assert(calc_epochal_from_yd(2020, 0) is errors::invalid,
+ "calc_epochal_from_yd() did not reject invalid yearday");
+ assert(calc_epochal_from_yd(2020, 400) is errors::invalid,
+ "calc_epochal_from_yd() did not reject invalid yearday");
+};
+
@test fn calc_ymd() void = {
const cases = [
(-999999, (-0768, 02, 05)),
