From ffc67884330a3f3d53d4da0d33a9d479e1653394 Mon Sep 17 00:00:00 2001
From: Hamza Hamidi <22576950+hamzahamidi@users.noreply.github.com>
Date: Sat, 29 Aug 2026 21:46:53 +0200
Subject: [PATCH] feat(duration): parse time strings like HH:mm:ss into
 durations

Matches moment.js behavior for creating durations from colon-separated
time strings: HH:mm:ss, HH:mm, days.HH:mm:ss, and fractional seconds.

Closes #1146
---
 src/plugin/duration/index.js | 12 +++++++++++
 test/plugin/duration.test.js | 42 ++++++++++++++++++++++++++++++++++++
 2 files changed, 54 insertions(+)

diff --git a/src/plugin/duration/index.js b/src/plugin/duration/index.js
index 5aaacee21..4b9c60894 100644
--- a/src/plugin/duration/index.js
+++ b/src/plugin/duration/index.js
@@ -10,6 +10,7 @@ const MILLISECONDS_A_YEAR = MILLISECONDS_A_DAY * 365
 const MILLISECONDS_A_MONTH = MILLISECONDS_A_YEAR / 12
 
 const DURATION_REGEX_PARSE = /^(-|\+)?P(?:([-+]?[0-9,.]*)Y)?(?:([-+]?[0-9,.]*)M)?(?:([-+]?[0-9,.]*)W)?(?:([-+]?[0-9,.]*)D)?(?:T(?:([-+]?[0-9,.]*)H)?(?:([-+]?[0-9,.]*)M)?(?:([-+]?[0-9,.]*)S)?)?$/
+const TIME_REGEX_PARSE = /^(-|\+)?(?:(\d*)[. ])?(\d+):(\d+)(?::(\d+)(\.\d*)?)?$/
 const DURATION_REGEX_FORMAT = /\[([^\]]+)]|YYYY|YY|Y|M{1,2}|D{1,2}|H{1,2}|m{1,2}|s{1,2}|SSS/g
 
 const unitToMS = {
@@ -97,6 +98,17 @@ class Duration {
         this.calMilliseconds()
         return this
       }
+      const t = input.match(TIME_REGEX_PARSE)
+      if (t) {
+        const sign = t[1] === '-' ? -1 : 1
+        this.$d.days = sign * (t[2] ? Number(t[2]) : 0)
+        this.$d.hours = sign * Number(t[3])
+        this.$d.minutes = sign * Number(t[4])
+        this.$d.seconds = sign * (t[5] ? Number(t[5]) : 0)
+        this.$d.milliseconds = sign * (t[6] ? Math.round(Number(`0${t[6]}`) * 1000) : 0)
+        this.calMilliseconds()
+        return this
+      }
     }
     return this
   }
diff --git a/test/plugin/duration.test.js b/test/plugin/duration.test.js
index f9a4c7cf4..7f13d693e 100644
--- a/test/plugin/duration.test.js
+++ b/test/plugin/duration.test.js
@@ -88,6 +88,48 @@ describe('Creating', () => {
   })
 })
 
+describe('Parse time string', () => {
+  it('HH:mm:ss', () => {
+    const d = dayjs.duration('02:04:33')
+    expect(d.hours()).toBe(2)
+    expect(d.minutes()).toBe(4)
+    expect(d.seconds()).toBe(33)
+    expect(d.asSeconds()).toBe(7473)
+    expect(d.toISOString()).toBe('PT2H4M33S')
+  })
+  it('HH:mm', () => {
+    const d = dayjs.duration('23:59')
+    expect(d.hours()).toBe(23)
+    expect(d.minutes()).toBe(59)
+    expect(d.seconds()).toBe(0)
+    expect(d.toISOString()).toBe('PT23H59M')
+  })
+  it('days.HH:mm:ss', () => {
+    const d = dayjs.duration('7.23:59:59')
+    expect(d.days()).toBe(7)
+    expect(d.hours()).toBe(23)
+    expect(d.minutes()).toBe(59)
+    expect(d.seconds()).toBe(59)
+  })
+  it('HH:mm:ss.SSS (fractional seconds)', () => {
+    const d = dayjs.duration('23:59:59.999')
+    expect(d.hours()).toBe(23)
+    expect(d.minutes()).toBe(59)
+    expect(d.seconds()).toBe(59)
+    expect(d.milliseconds()).toBe(999)
+  })
+  it('negative time string', () => {
+    const d = dayjs.duration('-23:59:59')
+    expect(d.hours()).toBe(-23)
+    expect(d.minutes()).toBe(-59)
+    expect(d.seconds()).toBe(-59)
+    expect(d.toISOString()).toBe('-PT23H59M59S')
+  })
+  it('Invalid string still returns P0D', () => {
+    expect(dayjs.duration('Invalid').toISOString()).toBe('P0D')
+  })
+})
+
 describe('Parse ISO string', () => {
   it('Full ISO string', () => {
     expect(dayjs.duration('P7Y6M4DT3H2M1S').toISOString()).toBe('P7Y6M4DT3H2M1S')