Temporal: Coverage for wrapping at the end of the month (#4695)

Covers Indian, Hijri, and Persian calendars

Author: catamorphism

test/built-ins/Temporal/PlainDate/prototype/since/wrapping-at-end-of-month.js

@@ -1,4 +1,4 @@
-// Copyright (C) 2024 Igalia, S.L. All rights reserved.
+// Copyright (C) 2025 Igalia, S.L. All rights reserved.
 // This code is governed by the BSD license found in the LICENSE file.
 
 /*---

test/intl402/Temporal/PlainDate/prototype/since/wrapping-at-end-of-month-buddhist.js

@@ -1,4 +1,4 @@
-// Copyright (C) 2024 Igalia, S.L. All rights reserved.
+// Copyright (C) 2025 Igalia, S.L. All rights reserved.
 // This code is governed by the BSD license found in the LICENSE file.
 
 /*---

test/intl402/Temporal/PlainDate/prototype/since/wrapping-at-end-of-month-chinese.js

@@ -1,4 +1,4 @@
-// Copyright (C) 2024 Igalia, S.L. All rights reserved.
+// Copyright (C) 2025 Igalia, S.L. All rights reserved.
 // This code is governed by the BSD license found in the LICENSE file.
 
 /*---

test/intl402/Temporal/PlainDate/prototype/since/wrapping-at-end-of-month-dangi.js

@@ -1,4 +1,4 @@
-// Copyright (C) 2024 Igalia, S.L. All rights reserved.
+// Copyright (C) 2025 Igalia, S.L. All rights reserved.
 // This code is governed by the BSD license found in the LICENSE file.
 
 /*---

test/intl402/Temporal/PlainDate/prototype/since/wrapping-at-end-of-month-indian.js

@@ -0,0 +1,72 @@
+// Copyright (C) 2025 Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-temporal.plaindate.prototype.since
+description: Tests balancing of days to months at end of month (indian calendar)
+includes: [temporalHelpers.js]
+features: [Temporal, Intl.Era-monthcode]
+---*/
+
+const calendar = "indian";
+
+// Difference between end of longer month to end of following shorter month
+{
+  const end = Temporal.PlainDate.from({ year: 1945, monthCode: "M07", day: 30, calendar });
+  for (const largestUnit of ["years", "months"]) {
+    TemporalHelpers.assertDuration(
+      Temporal.PlainDate.from({ year: 1945, monthCode: "M06", day: 30, calendar }).since(end, { largestUnit }),
+      0, -1, 0, 0, 0, 0, 0, 0, 0, 0,
+      `Bhadra 30th to Asvina 30th is one month (${largestUnit})`
+    );
+    TemporalHelpers.assertDuration(
+      Temporal.PlainDate.from({ year: 1945, monthCode: "M06", day: 31, calendar }).since(end, { largestUnit }),
+      0, 0, 0, -30, 0, 0, 0, 0, 0, 0,
+      `Bhadra 31st to Asvina 30th is 30 days, not one month (${largestUnit})`
+    );
+  }
+}
+
+// Difference between end of longer month to end of not-immediately-following
+// shorter month
+{
+  const end = Temporal.PlainDate.from({ year: 1945, monthCode: "M08", day: 30, calendar });
+  for (const largestUnit of ["years", "months"]) {
+    TemporalHelpers.assertDuration(
+      Temporal.PlainDate.from({ year: 1945, monthCode: "M06", day: 30, calendar }).since(end, { largestUnit }),
+      0, -2, 0, 0, 0, 0, 0, 0, 0, 0,
+      `Bhadra 30th to Kartika 30th is 2 months (${largestUnit})`
+    );
+    TemporalHelpers.assertDuration(
+      Temporal.PlainDate.from({ year: 1945, monthCode: "M06", day: 31, calendar }).since(end, { largestUnit }),
+      0, -1, 0, -30, 0, 0, 0, 0, 0, 0,
+      `Bhadra 31st to Kartika 30th is 1 month 30 days, not 2 months (${largestUnit})`
+    );
+  }
+}
+
+// Difference between end of longer month in one year to shorter month in
+// later year
+{
+  const end = Temporal.PlainDate.from({ year: 1950, monthCode: "M07", day: 30, calendar });
+  TemporalHelpers.assertDuration(
+    Temporal.PlainDate.from({ year: 1945, monthCode: "M06", day: 30, calendar }).since(end, { largestUnit: "months" }),
+    0, -61, 0, 0, 0, 0, 0, 0, 0, 0,
+    "Bhadra 30th 1945 to Asvina 30th 1950 is 61 months"
+  );
+  TemporalHelpers.assertDuration(
+    Temporal.PlainDate.from({ year: 1945, monthCode: "M06", day: 30, calendar }).since(end, { largestUnit: "years" }),
+    -5, -1, 0, 0, 0, 0, 0, 0, 0, 0,
+    "Bhadra 30th 1945 to Asvina 30th 1950 is 5 years, 1 month"
+  );
+  TemporalHelpers.assertDuration(
+    Temporal.PlainDate.from({ year: 1945, monthCode: "M06", day: 31, calendar }).since(end, { largestUnit: "months" }),
+    0, -60, 0, -30, 0, 0, 0, 0, 0, 0,
+    "Bhadra 31st 1945 to Asvina 30th 1950 is 60 months, 30 days, not 61 months"
+  );
+  TemporalHelpers.assertDuration(
+    Temporal.PlainDate.from({ year: 1945, monthCode: "M06", day: 31, calendar }).since(end, { largestUnit: "years" }),
+    -5, 0, 0, -30, 0, 0, 0, 0, 0, 0,
+    "Bhadra 31st 1945 to Asvina 30th 1950 is 5 years, 30 days"
+  );
+}

test/intl402/Temporal/PlainDate/prototype/since/wrapping-at-end-of-month-islamic-civil.js

@@ -0,0 +1,72 @@
+// Copyright (C) 2025 Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-temporal.plaindate.prototype.since
+description: Tests balancing of days to months at end of month (Islamic civil calendar)
+includes: [temporalHelpers.js]
+features: [Temporal, Intl.Era-monthcode]
+---*/
+
+const calendar = "islamic-civil";
+
+// Difference between end of longer month to end of following shorter month
+{
+  const end = Temporal.PlainDate.from({ year: 1400, monthCode: "M02", day: 29, calendar });
+  for (const largestUnit of ["years", "months"]) {
+    TemporalHelpers.assertDuration(
+      Temporal.PlainDate.from({ year: 1400, monthCode: "M01", day: 29, calendar }).since(end, { largestUnit }),
+      0, -1, 0, 0, 0, 0, 0, 0, 0, 0,
+      `Muharram 29th to Safar 29th is one month (${largestUnit})`
+    );
+    TemporalHelpers.assertDuration(
+      Temporal.PlainDate.from({ year: 1400, monthCode: "M01", day: 30, calendar }).since(end, { largestUnit }),
+      0, 0, 0, -29, 0, 0, 0, 0, 0, 0,
+      `Muharram 30th to Safar 29th is 29 days, not one month (${largestUnit})`
+    );
+  }
+}
+
+// Difference between end of longer month to end of not-immediately-following
+// shorter month
+{
+  const end = Temporal.PlainDate.from({ year: 1400, monthCode: "M04", day: 29, calendar });
+  for (const largestUnit of ["years", "months"]) {
+    TemporalHelpers.assertDuration(
+      Temporal.PlainDate.from({ year: 1400, monthCode: "M01", day: 29, calendar }).since(end, { largestUnit }),
+      0, -3, 0, 0, 0, 0, 0, 0, 0, 0,
+      `Muharram 29th to Thani 29th is 3 months (${largestUnit})`
+    );
+    TemporalHelpers.assertDuration(
+      Temporal.PlainDate.from({ year: 1400, monthCode: "M01", day: 30, calendar }).since(end, { largestUnit }),
+      0, -2, 0, -29, 0, 0, 0, 0, 0, 0,
+      `Muharram 30th to Thani 29th is 2 months 29 days, not 3 months (${largestUnit})`
+    );
+  }
+}
+
+// Difference between end of longer month in one year to shorter month in
+// later year
+{
+  const end = Temporal.PlainDate.from({ year: 1403, monthCode: "M02", day: 29, calendar });
+  TemporalHelpers.assertDuration(
+    Temporal.PlainDate.from({ year: 1400, monthCode: "M11", day: 29, calendar }).since(end, { largestUnit: "months" }),
+    0, -27, 0, 0, 0, 0, 0, 0, 0, 0,
+    "Qadah 29th 1400 to Safar 29th 1403 is 27 months"
+  );
+  TemporalHelpers.assertDuration(
+    Temporal.PlainDate.from({ year: 1400, monthCode: "M11", day: 29, calendar }).since(end, { largestUnit: "years" }),
+    -2, -3, 0, 0, 0, 0, 0, 0, 0, 0,
+    "Qadah 29th 1400 to Safar 29th 1403 is 2 years, 3 months"
+  );
+  TemporalHelpers.assertDuration(
+    Temporal.PlainDate.from({ year: 1400, monthCode: "M11", day: 30, calendar }).since(end, { largestUnit: "months" }),
+    0, -26, 0, -29, 0, 0, 0, 0, 0, 0,
+    "Qadah 30th 1400 to Safar 29th 1403 is 26 months, 29 days, not 27 months"
+  );
+  TemporalHelpers.assertDuration(
+    Temporal.PlainDate.from({ year: 1400, monthCode: "M11", day: 30, calendar }).since(end, { largestUnit: "years" }),
+    -2, -2, 0, -29, 0, 0, 0, 0, 0, 0,
+    "Qadah 30th 1400 to Safar 29th 1403 is 2 years, 2 months, 29 days, not 2 years 3 months"
+  );
+}

test/intl402/Temporal/PlainDate/prototype/since/wrapping-at-end-of-month-islamic-tbla.js

@@ -0,0 +1,72 @@
+// Copyright (C) 2025 Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-temporal.plaindate.prototype.since
+description: Tests balancing of days to months at end of month (Islamic tbla calendar)
+includes: [temporalHelpers.js]
+features: [Temporal, Intl.Era-monthcode]
+---*/
+
+const calendar = "islamic-tbla";
+
+// Difference between end of longer month to end of following shorter month
+{
+  const end = Temporal.PlainDate.from({ year: 1970, monthCode: "M02", day: 29, calendar });
+  for (const largestUnit of ["years", "months"]) {
+    TemporalHelpers.assertDuration(
+      Temporal.PlainDate.from({ year: 1970, monthCode: "M01", day: 29, calendar }).since(end, { largestUnit }),
+      0, -1, 0, 0, 0, 0, 0, 0, 0, 0,
+      `Muharram 29th to Safar 29th is one month (${largestUnit})`
+    );
+    TemporalHelpers.assertDuration(
+      Temporal.PlainDate.from({ year: 1970, monthCode: "M01", day: 30, calendar }).since(end, { largestUnit }),
+      0, 0, 0, -29, 0, 0, 0, 0, 0, 0,
+      `Muharram 30th to Safar 29th is 29 days, not one month (${largestUnit})`
+    );
+  }
+}
+
+// Difference between end of longer month to end of not-immediately-following
+// shorter month
+{
+  const end = Temporal.PlainDate.from({ year: 1970, monthCode: "M04", day: 29, calendar });
+  for (const largestUnit of ["years", "months"]) {
+    TemporalHelpers.assertDuration(
+      Temporal.PlainDate.from({ year: 1970, monthCode: "M01", day: 29, calendar }).since(end, { largestUnit }),
+      0, -3, 0, 0, 0, 0, 0, 0, 0, 0,
+      `Muharram 29th to Thani 29th is 3 months (${largestUnit})`
+    );
+    TemporalHelpers.assertDuration(
+      Temporal.PlainDate.from({ year: 1970, monthCode: "M01", day: 30, calendar }).since(end, { largestUnit }),
+      0, -2, 0, -29, 0, 0, 0, 0, 0, 0,
+      `Muharram 30th to Thani 29th is 2 months 29 days, not 3 months (${largestUnit})`
+    );
+  }
+}
+
+// Difference between end of longer month in one year to shorter month in
+// later year
+{
+  const end = Temporal.PlainDate.from({ year: 1973, monthCode: "M02", day: 29, calendar });
+  TemporalHelpers.assertDuration(
+    Temporal.PlainDate.from({ year: 1970, monthCode: "M11", day: 29, calendar }).since(end, { largestUnit: "months" }),
+    0, -27, 0, 0, 0, 0, 0, 0, 0, 0,
+    "Qadah 29th 1970 to Safar 29th 1973 is 27 months"
+  );
+  TemporalHelpers.assertDuration(
+    Temporal.PlainDate.from({ year: 1970, monthCode: "M11", day: 29, calendar }).since(end, { largestUnit: "years" }),
+    -2, -3, 0, 0, 0, 0, 0, 0, 0, 0,
+    "Qadah 29th 1970 to Safar 29th 1973 is 2 years, 3 months"
+  );
+  TemporalHelpers.assertDuration(
+    Temporal.PlainDate.from({ year: 1970, monthCode: "M11", day: 30, calendar }).since(end, { largestUnit: "months" }),
+    0, -26, 0, -29, 0, 0, 0, 0, 0, 0,
+    "Qadah 30th 1970 to Safar 29th 1973 is 26 months, 29 days, not 27 months"
+  );
+  TemporalHelpers.assertDuration(
+    Temporal.PlainDate.from({ year: 1970, monthCode: "M11", day: 30, calendar }).since(end, { largestUnit: "years" }),
+    -2, -2, 0, -29, 0, 0, 0, 0, 0, 0,
+    "Qadah 30th 1970 to Safar 29th 1973 is 2 years, 2 months, 29 days, not 2 years 3 months"
+  );
+}

test/intl402/Temporal/PlainDate/prototype/since/wrapping-at-end-of-month-islamic-umalqura.js

@@ -0,0 +1,72 @@
+// Copyright (C) 2025 Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-temporal.plaindate.prototype.since
+description: Tests balancing of days to months at end of month (Islamic Umm al-Qura calendar)
+includes: [temporalHelpers.js]
+features: [Temporal, Intl.Era-monthcode]
+---*/
+
+const calendar = "islamic-umalqura";
+
+// Difference between end of longer month to end of following shorter month
+{
+  const end = Temporal.PlainDate.from({ year: 1970, monthCode: "M02", day: 29, calendar });
+  for (const largestUnit of ["years", "months"]) {
+    TemporalHelpers.assertDuration(
+      Temporal.PlainDate.from({ year: 1970, monthCode: "M01", day: 29, calendar }).since(end, { largestUnit }),
+      0, -1, 0, 0, 0, 0, 0, 0, 0, 0,
+      `Muharram 29th to Safar 29th is one month (${largestUnit})`
+    );
+    TemporalHelpers.assertDuration(
+      Temporal.PlainDate.from({ year: 1970, monthCode: "M01", day: 30, calendar }).since(end, { largestUnit }),
+      0, 0, 0, -29, 0, 0, 0, 0, 0, 0,
+      `Muharram 30th to Safar 29th is 29 days, not one month (${largestUnit})`
+    );
+  }
+}
+
+// Difference between end of longer month to end of not-immediately-following
+// shorter month
+{
+  const end = Temporal.PlainDate.from({ year: 1970, monthCode: "M04", day: 29, calendar });
+  for (const largestUnit of ["years", "months"]) {
+    TemporalHelpers.assertDuration(
+      Temporal.PlainDate.from({ year: 1970, monthCode: "M01", day: 29, calendar }).since(end, { largestUnit }),
+      0, -3, 0, 0, 0, 0, 0, 0, 0, 0,
+      `Muharram 29th to Thani 29th is 3 months (${largestUnit})`
+    );
+    TemporalHelpers.assertDuration(
+      Temporal.PlainDate.from({ year: 1970, monthCode: "M01", day: 30, calendar }).since(end, { largestUnit }),
+      0, -2, 0, -29, 0, 0, 0, 0, 0, 0,
+      `Muharram 30th to Thani 29th is 2 months 29 days, not 3 months (${largestUnit})`
+    );
+  }
+}
+
+// Difference between end of longer month in one year to shorter month in
+// later year
+{
+  const end = Temporal.PlainDate.from({ year: 1973, monthCode: "M02", day: 29, calendar });
+  TemporalHelpers.assertDuration(
+    Temporal.PlainDate.from({ year: 1970, monthCode: "M11", day: 29, calendar }).since(end, { largestUnit: "months" }),
+    0, -27, 0, 0, 0, 0, 0, 0, 0, 0,
+    "Qadah 29th 1970 to Safar 29th 1973 is 27 months"
+  );
+  TemporalHelpers.assertDuration(
+    Temporal.PlainDate.from({ year: 1970, monthCode: "M11", day: 29, calendar }).since(end, { largestUnit: "years" }),
+    -2, -3, 0, 0, 0, 0, 0, 0, 0, 0,
+    "Qadah 29th 1970 to Safar 29th 1973 is 2 years, 3 months"
+  );
+  TemporalHelpers.assertDuration(
+    Temporal.PlainDate.from({ year: 1970, monthCode: "M11", day: 30, calendar }).since(end, { largestUnit: "months" }),
+    0, -26, 0, -29, 0, 0, 0, 0, 0, 0,
+    "Qadah 30th 1970 to Safar 29th 1973 is 26 months, 29 days, not 27 months"
+  );
+  TemporalHelpers.assertDuration(
+    Temporal.PlainDate.from({ year: 1970, monthCode: "M11", day: 30, calendar }).since(end, { largestUnit: "years" }),
+    -2, -2, 0, -29, 0, 0, 0, 0, 0, 0,
+    "Qadah 30th 1970 to Safar 29th 1973 is 2 years, 2 months, 29 days, not 2 years 3 months"
+  );
+}