Files
typikon/docs/versioning.md
funkpower d0efc56312 The Sundays the calendar was not naming, and a calendar that keeps every day
Nine Sundays went unnamed in every jurisdiction. Three were missing from the
movable cycle outright: the Paralytic, the Samaritan Woman and the Blind Man,
so the fourth, fifth and sixth Sundays of Pascha reported only the saint of the
fixed date. Six more are reckoned from a fixed feast rather than from Pascha —
before and after the Exaltation, the Forefathers, before and after the
Nativity, before and after the Theophany — and were not modelled at all.

The three Pentecostarion Sundays rank with Thomas Sunday and the Myrrh-bearing
Women, so a vigil-rank saint still keeps the day and the Sunday is commemorated
on it. The six fixed-cycle ones never name a day: they are found in
ecclesiastical space, so the old calendar and the new get them on the right
morning, and they join the commemorations. Where a short window holds no Sunday
the Typikon says what to do and this follows it; where the books disagree, the
day goes unmarked rather than carrying an answer this calendar cannot defend.

`week` says where a day falls in the count from Pentecost, which is how the
books head the long ordinary stretch. It runs on across the new year and stops
at the Triodion, whose Sundays have names instead of numbers.

`--every-day` gives ics an event for every day, ferias included. The default
still thins the calendar, which is right for a subscription and wrong for a
reader who wants the saint of each morning; and the description now leads with
the commemorations rather than burying them under the church date.

Checked against 1.1.2 over every jurisdiction from 2015 to 2035: rank, feast
and title move on the three new Sundays and nowhere else. No fast, obligation,
binding or season changes on any day.
2026-09-21 09:28:27 -04:00

131 lines
5.0 KiB
Markdown

# Versioning
`typikon` follows semantic versioning from 1.0.0 onward. This page says what
that covers, because a calendar has a wider public surface than a library
usually does: four things depend on it, and only one of them is a function
signature.
## What is stable
A **major** version is required to change any of these.
### The JSON
Field names, their types, and whether a field can be null. Front ends are the
thing most likely to be written by someone else, and a schema that shifts
underneath them is a bad neighbour. As of 1.0.0:
```
date weekday jurisdiction calendar churchDate season cycle feast rank sign
tradition title commemorations fast fastLabel emoji reason obligation binds
pascha daysToPascha julianOffset
```
`week` was added in 1.2.0.
`fastLabel`, `emoji` and `reason` are **presentation**: the fields are always
there, and their wording is not stable. Key on `fast`, `season`, `rank`,
`obligation` and `binds`.
Adding a field is a **minor** change, so read the object by key and ignore what
you do not recognise. `season`, `cycle`, `feast`, `rank`, `sign` and
`obligation` are null on ordinary days, and `week` is null through the Triodion
and the Pentecostarion.
Two semantics worth stating because the names do not carry them:
- **`daysToPascha` is signed**, and counts to the Pascha of that day's own
civil year. It is negative after Pascha has passed. 31 December reports
about -263, not the days until the next one.
- **`julianOffset`** is reported for every jurisdiction, including those that
do not use the Julian menologion.
- **`binds` is null unless the day binds.** Most jurisdictions legislate no
binding fast at all, which is a different fact from a day that happens to
oblige nothing, and the null says which.
### The fasting levels
`strict` `xerophagy` `wine_oil` `fish` `dairy` `none`, and their order from
strictest to laxest. Code that compares them may rely on that order.
### The jurisdiction and calendar keys
`old` `new` `western`, and every jurisdiction key `typikon --list` prints.
A key is never renamed or removed in a minor version. New ones are added
freely.
### The command line
Flag names and what they do, the column names `--format csv` accepts, and the
exit codes:
| | |
|---|---|
| 0 | it answered |
| 1 | it ran and the result is incomplete, as when a fetched menaion is missing days |
| 2 | it was asked for something it could not do | `--json` and `--ics` remain as shorthand
for `--format`.
### The Rust and Python APIs
Public items in the crate root and the modules `calendars`, `paschalion`,
`seasons`, `fasting`, `jurisdictions`, `menologion`, `day`, `export`, `config`;
and in Python, the module's functions and the attributes of `Day`.
`Day.to_dict()` in Python carries the same fields as the JSON, in snake_case
rather than camelCase, which is the one deliberate difference between them.
### The C ABI
Every `typikon_*` symbol declared in `include/typikon.h`, and the meaning of
what it returns. `typikon_abi_version()` is bumped when any of that changes;
additions leave it alone, so a caller can require a minimum and get everything
after it.
Dates cross as Julian Day Numbers and a day is opaque, so the ABI carries no
struct layout and a rebuilt library stays loadable against a header that has
not moved.
### The JavaScript package
The functions the npm package exports, and the `Day`, `Options` and
`JurisdictionInfo` types in its `.d.ts`. A day is the JSON above, with the same
field names; `undefined` never appears where the JSON has `null`.
The one deliberate difference from every other binding: there is no remembered
default jurisdiction, because a browser has nowhere to keep one. The default is
the New Calendar.
## What is not stable
- **The text output.** It is for a person to read, and it changes when a better
arrangement is found. Parse the JSON, CSV or TSV instead.
- **`reason`, `fastLabel` and `emoji`.** They explain and present a decision to
a reader; they are not identifiers. The fields themselves are stable, their
wording is not.
- **The menologion.** Commemorations get added, corrected and reworded. See
below.
- **Anything not listed above**, including every private item and the layout of
fetched menaia on disk.
## Corrections to the calendar itself
This is the category semver does not have a word for, and it is the one that
matters most here.
A correction to a fast rule, a feast rank or a commemoration changes what the
program tells you about a day. It breaks no interface, so by semver it is a
patch. But it changes what someone is told to eat, and a user who has noticed a
disagreement with their parish deserves to know it moved.
So: **every change to what a day reports is called out in the changelog under
"Calendar"**, with the days affected, whatever the version number does. If a
correction changes a day you care about, the changelog is where it will say so.
Adding a jurisdiction, a menaion, a tradition or a binding is a minor version.
Correcting an existing one is a patch, and is announced.
## Releasing
See [releasing.md](releasing.md). The version lives only in `Cargo.toml`.