Slot validation reports every problem at once rather than the first, so
someone fixing a day's hours on a phone in the shop is not sent round
the loop three times. It covers the format, the ordering, overlaps and
the three-slot ceiling. Slots that merely touch are accepted: 13:00
closing and 13:00 reopening is pointless but not contradictory, and
refusing it would only annoy whoever typed it.
Month and day names are spelled out rather than taken from Intl. The
screen text feeds a content hash that decides whether the e-ink panel
redraws at all, so it has to be byte-stable and must not shift because
a container image ships different ICU locale data.
English uses the twelve-hour clock, as the payload contract specifies:
"Closes at 6:30 pm". Noon and midnight are covered.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_012cSY9pVhZmJUKNN7wf1Myd
This is the business core, written before any UI as the spec requires.
It is pure: no I/O, no database, no clock of its own. Everything arrives
in a ScheduleContext, so every rule below is exhaustively testable.
The engine works on civil (wall-clock) values rather than instants. A
slot that runs 10:00-18:30 runs 10:00-18:30 on the nights the clocks
change too, and day arithmetic goes through UTC, which has no daylight
saving. That turns the March and October switches from edge cases into
non-events, and the tests pin both of them.
Priority order, highest first: a dated exception, a vacation period, a
public holiday the shop closes for, the reference week, then closed.
Exceptions are badged by their stated reason rather than by who created
them, so a holiday imported by the sync shows as a holiday in the UI.
The search for the next opening is bounded to fourteen days. A shop that
is closed forever must not make the server spin; past the horizon the
screen simply says nothing about reopening. Both the never-open week and
the beyond-the-horizon reopening are covered.
"Soon" is strictly under thirty minutes, so a change exactly half an
hour away still reads as plain OPEN or CLOSED.
55 tests; lib/schedule sits at 97% statements and 93% branches against
an 85% floor. The thresholds were verified to actually fail the build
before being committed.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_012cSY9pVhZmJUKNN7wf1Myd
vliaudatandClaude Opus 5