@ethisyscore/core-utils

Framework-agnostic utilities shared by the EthisysCore monolith and plugins. Pure TypeScript — no React, no MUI. Utilities are grouped by domain; today that is date.

Install

npm install @ethisyscore/core-utils

date-fns is a runtime dependency. dayjs is an optional peer dependency — only needed if you import the ./date/dayjs sub-path.

Usage

// Everything (umbrella entry)
import { formatDateSafe, dateOnlyToIsoUtc, formatDurationNumber } from "@ethisyscore/core-utils";

// Or import the date group directly
import { addDaysToIsoDate, toHHmmss } from "@ethisyscore/core-utils/date";

// dayjs-backed picker helper (requires dayjs)
import { dayjsToIsoDayBoundary } from "@ethisyscore/core-utils/date/dayjs";

What's inside (./date)

| Area | Exports | | --- | --- | | Format constants | DATE_FORMAT, DISPLAY_DATE_FORMAT, AUDIT_DATE_FORMAT, DAY_DATE_FORMAT, DAY_MONTH_FORMAT, DAY_MONTH_YEAR_FORMAT, TIME_FORMAT, SHORT_DATETIME_FORMAT | | ISO / timezone-safe | isDateOnlyString, formatDate, getTodayIsoDate, getMonthStartIso, getMonthEndIso, parseIsoDateLocal, addDaysToIsoDate, toDateOnlyString | | Display formatting | formatDateString, formatDateSafe, formatDateWithOrdinal, formatTimeAgo | | Duration / timespan | timespanToMilliseconds, millisecondsToHours, hoursToMilliseconds, formatMillisecondsAsTimeSpent, formatDuration, formatDurationNumber, toHHmm, toHHmmss | | Wire boundary (<input> ⇄ .NET DateTimeOffset) | isoToDateInput, dateInputToIso, dateOnlyToIsoUtc, nowLocalDateTimeInputValue, localDateTimeInputToIsoUtc, isoUtcToLocalDateTimeInput, ensureUtcIso | | Ranges / timezone | getDateRange, computeDateRange, currentMonthRangeUtc, getCurrentOffsetMinutes | | dayjs sub-path | dayjsToIsoDayBoundary |

The wire-boundary helpers exist to bridge the naive local strings emitted by <input type="date"> / <input type="datetime-local"> to full ISO-8601 UTC, avoiding the offset/DST drift that occurs when a .NET DateTimeOffset endpoint reinterprets a no-suffix timestamp as UTC.

Scripts

npm run build   # tsup → ESM + CJS + d.ts
npm test        # vitest
npm run lint    # tsc --noEmit