chore: bump to v1.0.4

toHijri() now passes Date.UTC(year, month, date) to hijri-core instead of the raw
instant from this.toDate(). Fixes wrong-Hijri-day results around UTC-midnight on
hosts east or west of UTC. Lock-step with hijri-core fix/utc-day-boundary.

.gitignore

@@ -6,6 +6,7 @@ dist/
 .claude/
 .env
 .env.*
+coverage/
 
 # AI agent directories
 .cursor/

CHANGELOG.md

@@ -5,7 +5,15 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
-## [Unreleased]
+## [1.0.4] - 2026-06-13
+
+### Fixed
+- Published package now includes `dist/index.d.mts` so ESM type resolution under `node16`/`nodenext` resolves the import condition.
+
+## [1.0.3] - 2026-06-10
+
+### Fixed
+- `.toHijri()` now converts the calendar date the dayjs instance displays (via `Date.UTC(year, month, date)`) instead of passing the raw instant to hijri-core. Fixes wrong-Hijri-day results around UTC-midnight instants on hosts east or west of UTC. Requires hijri-core 1.0.3.
 
 ## [1.0.2] - 2026-05-30
 

README.md

@@ -36,6 +36,12 @@ dayjs.fromHijri(1444, 10, 1).format('YYYY-MM-DD'); // '2023-04-21'
 
 Full API reference, examples, and architecture notes are on the [GitHub Wiki](https://github.com/acamarata/dayjs-hijri-plus/wiki).
 
+## Day boundaries and time zones
+
+`.toHijri()` converts the calendar date the dayjs instance displays — the same date you would read off the screen — regardless of the host's system timezone or whether the dayjs `utc` plugin is active. A call like `dayjs('2025-03-01').toHijri()` always maps the 1st of March 2025, not whatever local instant that string resolves to in UTC.
+
+Religious start-of-day at sunset is out of scope. Sunset-aware day boundaries require external prayer-time data and are not handled here.
+
 ## Related
 
 - [hijri-core](https://github.com/acamarata/hijri-core): the zero-dependency Hijri calendar engine this plugin wraps

eslint.config.mjs

@@ -5,10 +5,14 @@ import { typescript } from '@acamarata/eslint-config';
 
 export default [
   {
+    files: ['**/*.ts', '**/*.tsx'],
     plugins: { '@typescript-eslint': tsPlugin },
-    languageOptions: { parser: tsParser },
+    languageOptions: {
+      parser: tsParser,
+      parserOptions: { project: true, tsconfigRootDir: import.meta.dirname },
+    },
   },
-  ...typescript,
+  ...typescript.map((cfg) => ({ ...cfg, files: ['**/*.ts', '**/*.tsx'] })),
   eslintConfigPrettier,
   {
     ignores: ['dist/', 'node_modules/', 'test.mjs', 'test-cjs.cjs'],

package.json

@@ -1,6 +1,6 @@
 {
   "name": "dayjs-hijri-plus",
-  "version": "1.0.2",
+  "version": "1.0.4",
   "description": "Day.js plugin for Hijri calendar conversion and formatting. Supports Umm al-Qura and FCNA calendars via hijri-core.",
   "author": "Aric Camarata",
   "license": "MIT",
@@ -37,7 +37,7 @@
     "lint": "eslint src/",
     "format": "prettier --write src/",
     "format:check": "prettier --check src/",
-    "prepublishOnly": "tsup",
+    "prepack": "pnpm run build",
     "coverage": "c8 --reporter=lcov --reporter=text node test.mjs",
     "docs": "typedoc --out .github/wiki/api src/index.ts",
     "postbuild": "cp dist/index.d.ts dist/index.d.mts"
@@ -60,15 +60,17 @@
   },
   "devDependencies": {
     "@acamarata/eslint-config": "^0.1.0",
-    "c8": "^10.1.3",
     "@acamarata/prettier-config": "^0.1.0",
     "@acamarata/tsconfig": "^0.1.0",
     "@eslint/js": "^10.0.1",
     "@types/node": "^25.3.5",
+    "@typescript-eslint/eslint-plugin": "^8.56.1",
+    "@typescript-eslint/parser": "^8.56.1",
+    "c8": "^10.1.3",
     "dayjs": "^1.11.0",
     "eslint": "^10.0.3",
     "eslint-config-prettier": "^10.1.8",
-    "hijri-core": "^1.0.0",
+    "hijri-core": "^1.0.3",
     "prettier": "^3.8.1",
     "tsup": "^8.0.0",
     "typedoc": "^0.28.19",

pnpm-lock.yaml

@@ -23,6 +23,12 @@ importers:
       '@types/node':
         specifier: ^25.3.5
         version: 25.3.5
+      '@typescript-eslint/eslint-plugin':
+        specifier: ^8.56.1
+        version: 8.56.1(@typescript-eslint/parser@8.56.1(eslint@10.0.3)(typescript@5.9.3))(eslint@10.0.3)(typescript@5.9.3)
+      '@typescript-eslint/parser':
+        specifier: ^8.56.1
+        version: 8.56.1(eslint@10.0.3)(typescript@5.9.3)
       c8:
         specifier: ^10.1.3
         version: 10.1.3
@@ -36,8 +42,8 @@ importers:
         specifier: ^10.1.8
         version: 10.1.8(eslint@10.0.3)
       hijri-core:
-        specifier: ^1.0.0
-        version: 1.0.0
+        specifier: ^1.0.3
+        version: 1.0.3
       prettier:
         specifier: ^3.8.1
         version: 3.8.1
@@ -818,8 +824,8 @@ packages:
     resolution: {integrity: sha512-EykJT/Q1KjTWctppgIAgfSO0tKVuZUjhgMr17kqTumMl6Afv3EISleU7qZUzoXDFTAHTDC4NOoG/ZxU3EvlMPQ==}
     engines: {node: '>=8'}
 
-  hijri-core@1.0.0:
-    resolution: {integrity: sha512-wImBZLBKbEWEEUE1nrc1CFY/uvx4XjGNWYChImJZlswXIVhrBCzSVaj6DP1AU2gUMJ6KDh2ygXo/u/Qx232CXA==}
+  hijri-core@1.0.3:
+    resolution: {integrity: sha512-ONT5gp+Z/lzT/BbWKS0F8lcKK9T/H6jc95NLQE4Angdt7Uimo4KkmSt/qn9odaQRp1pX0RjA65QRcR4miF7XxA==}
     engines: {node: '>=20'}
 
   html-escaper@2.0.2:
@@ -1880,7 +1886,7 @@ snapshots:
 
   has-flag@4.0.0: {}
 
-  hijri-core@1.0.0: {}
+  hijri-core@1.0.3: {}
 
   html-escaper@2.0.2: {}
 

src/index.ts

@@ -1,9 +1,9 @@
-import type { PluginFunc } from 'dayjs';
-import { toHijri, toGregorian, hmLong, hmMedium, hwLong, hwShort, hwNumeric } from 'hijri-core';
-import type { ConversionOptions, HijriDate } from './types';
+import type { PluginFunc } from "dayjs";
+import { toHijri, toGregorian, hmLong, hmMedium, hwLong, hwShort, hwNumeric } from "hijri-core";
+import type { ConversionOptions, HijriDate } from "./types";
 
 // Augment Day.js to expose plugin methods on the instance type.
-declare module 'dayjs' {
+declare module "dayjs" {
   interface Dayjs {
     /**
      * Convert the Day.js date to a Hijri date.
@@ -91,7 +91,7 @@ declare module 'dayjs' {
 // Using the function declaration form (same pattern as dayjs timezone plugin)
 // because dayjs does not export an IStatic interface for module augmentation.
 // import('dayjs').Dayjs is used explicitly to satisfy the tsup DTS emitter.
-declare module 'dayjs' {
+declare module "dayjs" {
   /**
    * Construct a Day.js instance from a Hijri date.
    *
@@ -117,7 +117,7 @@ declare module 'dayjs' {
     hm: number,
     hd: number,
     opts?: ConversionOptions,
-  ): import('dayjs').Dayjs;
+  ): import("dayjs").Dayjs;
 }
 
 // Hijri-specific format tokens, ordered longest-first to prevent partial matches.
@@ -138,7 +138,7 @@ const HIJRI_TOKEN_RE = /iYYYY|iYY|iMMMM|iMMM|iMM|iM|iDD|iD|iEEEE|iEEE|iE|ioooo|i
  * @returns The bracket-escaped string.
  */
 function lit(value: string): string {
-  return '[' + value.split(']').join(']][') + ']';
+  return "[" + value.split("]").join("]][") + "]";
 }
 
 /**
@@ -167,7 +167,11 @@ const plugin: PluginFunc = (_option, dayjsClass, dayjsFactory) => {
   // ------------------------------------------------------------------ //
 
   dayjsClass.prototype.toHijri = function (opts?: ConversionOptions): HijriDate | null {
-    return toHijri(this.toDate(), opts);
+    // Build a UTC-noon Date from the calendar date this instance displays so
+    // that hijri-core's UTC-day contract reads the correct day regardless of
+    // the host timezone or whether the dayjs utc plugin is active.
+    // dayjs .month() is 0-based, matching Date.UTC's month parameter.
+    return toHijri(new Date(Date.UTC(this.year(), this.month(), this.date())), opts);
   };
 
   dayjsClass.prototype.isValidHijri = function (opts?: ConversionOptions): boolean {
@@ -191,7 +195,7 @@ const plugin: PluginFunc = (_option, dayjsClass, dayjsFactory) => {
     opts?: ConversionOptions,
   ): string {
     const hijri = this.toHijri(opts);
-    if (!hijri) return '';
+    if (!hijri) return "";
 
     // Day.js .day() returns 0 (Sunday) ... 6 (Saturday), matching the index
     // layout of hwLong, hwShort, and hwNumeric from hijri-core.
@@ -199,38 +203,38 @@ const plugin: PluginFunc = (_option, dayjsClass, dayjsFactory) => {
 
     const replaced = formatStr.replace(HIJRI_TOKEN_RE, (token) => {
       switch (token) {
-        case 'iYYYY':
-          return lit(String(hijri.hy).padStart(4, '0'));
-        case 'iYY':
-          return lit(String(hijri.hy % 100).padStart(2, '0'));
-        case 'iMMMM':
+        case "iYYYY":
+          return lit(String(hijri.hy).padStart(4, "0"));
+        case "iYY":
+          return lit(String(hijri.hy % 100).padStart(2, "0"));
+        case "iMMMM":
           // Non-null: hijri.hm is a valid Hijri month 1-12; hm-1 is always within hmLong bounds.
           // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
           return lit(hmLong[hijri.hm - 1]!);
-        case 'iMMM':
+        case "iMMM":
           // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
           return lit(hmMedium[hijri.hm - 1]!);
-        case 'iMM':
-          return lit(String(hijri.hm).padStart(2, '0'));
-        case 'iM':
+        case "iMM":
+          return lit(String(hijri.hm).padStart(2, "0"));
+        case "iM":
           return lit(String(hijri.hm));
-        case 'iDD':
-          return lit(String(hijri.hd).padStart(2, '0'));
-        case 'iD':
+        case "iDD":
+          return lit(String(hijri.hd).padStart(2, "0"));
+        case "iD":
           return lit(String(hijri.hd));
-        case 'iEEEE':
+        case "iEEEE":
           // Non-null: dow is always 0-6 (day of week), within hwLong bounds.
           // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
           return lit(hwLong[dow]!);
-        case 'iEEE':
+        case "iEEE":
           // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
           return lit(hwShort[dow]!);
-        case 'iE':
+        case "iE":
           // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
           return lit(String(hwNumeric[dow]!));
-        case 'ioooo':
-        case 'iooo':
-          return lit('AH');
+        case "ioooo":
+        case "iooo":
+          return lit("AH");
         default:
           return token;
       }
@@ -262,12 +266,14 @@ const plugin: PluginFunc = (_option, dayjsClass, dayjsFactory) => {
     if (!greg) {
       throw new Error(`Invalid or out-of-range Hijri date: ${hy}/${hm}/${hd}`);
     }
-    // Construct from ISO date string to avoid timezone offset issues.
-    // dayjsFactory(Date) interprets the Date in local time; a UTC-midnight Date
-    // in western timezones would resolve to the previous local day.
+    // Construct from an ISO date string (YYYY-MM-DD) so the result is the
+    // Gregorian calendar day that corresponds to the Hijri date, at local
+    // midnight in whatever timezone the consumer uses. Passing a raw Date
+    // object to dayjsFactory() would interpret it as a UTC instant and could
+    // land on the previous local day for hosts west of UTC.
     const y = greg.getUTCFullYear();
-    const mo = String(greg.getUTCMonth() + 1).padStart(2, '0');
-    const dy = String(greg.getUTCDate()).padStart(2, '0');
+    const mo = String(greg.getUTCMonth() + 1).padStart(2, "0");
+    const dy = String(greg.getUTCDate()).padStart(2, "0");
     return dayjsFactory(`${y}-${mo}-${dy}`);
   };
 };
@@ -278,13 +284,13 @@ export default plugin;
  * Re-exported from hijri-core for consumers who import from dayjs-hijri-plus.
  * Avoids requiring hijri-core as a direct dependency just to use these types.
  */
-export type { HijriDate, ConversionOptions } from './types';
+export type { HijriDate, ConversionOptions } from "./types";
 
 /**
  * Re-exported CalendarEngine interface from hijri-core.
  * Use this type to implement custom calendar engines for `registerCalendar`.
  */
-export type { CalendarEngine } from 'hijri-core';
+export type { CalendarEngine } from "hijri-core";
 
 /**
  * Re-exported registry API from hijri-core.
@@ -296,4 +302,4 @@ export type { CalendarEngine } from 'hijri-core';
  * registerCalendar('my-cal', myEngine);
  * listCalendars(); // ['uaq', 'fcna', 'my-cal']
  */
-export { registerCalendar, getCalendar, listCalendars } from 'hijri-core';
+export { registerCalendar, getCalendar, listCalendars } from "hijri-core";

src/types.ts

@@ -1,2 +1,2 @@
-import type { HijriDate, ConversionOptions } from 'hijri-core';
+import type { HijriDate, ConversionOptions } from "hijri-core";
 export type { HijriDate, ConversionOptions };

test-cjs.cjs

@@ -59,3 +59,16 @@ describe('CJS: isValidHijri', () => {
     assert.equal(dayjs(D_RAMADAN_1444).isValidHijri(), true);
   });
 });
+
+describe('CJS: UTC-day boundary (regression)', () => {
+  it('dayjs("2025-03-01").toHijri() -> 1 Ramadan 1446', () => {
+    const h = dayjs('2025-03-01').toHijri();
+    assert.deepEqual(h, { hy: 1446, hm: 9, hd: 1 });
+  });
+
+  it('round-trip: fromHijri(1446,9,1) then toHijri() -> {1446,9,1}', () => {
+    const d = dayjs.fromHijri(1446, 9, 1);
+    const h = d.toHijri();
+    assert.deepEqual(h, { hy: 1446, hm: 9, hd: 1 });
+  });
+});

test.mjs

@@ -102,3 +102,18 @@ describe('isValidHijri', () => {
     assert.equal(valid, true);
   });
 });
+
+describe('UTC-day boundary (regression)', () => {
+  // dayjs("YYYY-MM-DD") parses as local midnight — timezone-invariant anchor
+  // for toHijri now that the adapter reads the displayed calendar date.
+  it('dayjs("2025-03-01").toHijri() -> 1 Ramadan 1446', () => {
+    const h = dayjs('2025-03-01').toHijri();
+    assert.deepEqual(h, { hy: 1446, hm: 9, hd: 1 });
+  });
+
+  it('round-trip: fromHijri(1446,9,1) then toHijri() -> {1446,9,1}', () => {
+    const d = dayjs.fromHijri(1446, 9, 1);
+    const h = d.toHijri();
+    assert.deepEqual(h, { hy: 1446, hm: 9, hd: 1 });
+  });
+});