The changelog said nothing had been released since 1.0.0. Twenty-two builds
had shipped. Twenty-one entries sat under "## Unreleased" in a file with
exactly two headings, so a reader at any tag found no section for the version
they were holding.
Which release carried which entry is DERIVED, not guessed: for every line in
the region, the commit that introduced it, then the earliest tag containing
that commit. That yields seven releases - .22, .21, .20, .19, .14, .8 and .0.
No entry text changed. A verification pass compares the multiset of
non-heading lines before and after and refuses to write if anything was lost,
gained or duplicated; entries move under their release, so it compares as a
multiset rather than in order.
CHANGELOG.txt was kept BY HAND and drifted the moment the .md was
reorganised, which is the failure the plain-text-twin rule exists to prevent.
readme_txt.py becomes plaintext_twins.py and renders every pair. It also
drops <!-- --> markers, invisible in markdown and stray punctuation in a text
file - that is the whole of README.txt's diff.
The --check that keeps twins honest was never run. readme_txt.py shipped one
and its docstring claimed "the test suite runs --check"; nothing invoked it,
so a twin could disagree with its markdown indefinitely.
tests/PlainTextTwins.Tests.ps1 runs it.
That test skipped on its first run while claiming to pass: -Skip is evaluated
during DISCOVERY, before BeforeAll, so the python lookup left the flag $null.
Resolved in BeforeDiscovery, and when python really is absent the result is
INCONCLUSIVE rather than a green tick for a check that never happened.
Mutation-checked: appending one line to CHANGELOG.txt fails "every twin is in
sync with its markdown", and only that test.
tests: 243 passed, 0 failed, 1 skipped (the no-python reporter, correctly).
