Recent commits to derivepassphrase.git (6941e00680b380839a5b2c05783a8240ac5b77c1)

Use the "correct" wrong SSH_AUTH_SOCK value

2026-01-18T16:37:36+01:00

Some tests require a wrong SSH_AUTH_SOCK value where no SSH agent can be
listening, but which is nonetheless syntactically valid.  Since Windows
named pipes have a specific address format, syntactically valid but
wrong values look different on The Annoying OS than they look on POSIX.
So fill in wrong values OS-specifically, not generally: on POSIX, we use
what is clearly a directory, and on The Annoying OS, we use the common
pipe name prefix (which is also a directory).
</pre>

Prioritize WindowsNamedPipesNotAvailableError over other errors

2026-01-18T15:42:53+01:00

The SSH agent socket provider, by contract, must raise
`NotImplementedError` (or a subclass) if and only if the socket can
never be successfully constructed, on principle.  Conversely, if the
socket provider raises any other kind of error, then the socket *could*
be constructed on this system, principally.

In the specific case of Windows named pipes whose address is named by
the `SSH_AUTH_SOCK` environment variable, it is a programming error to
first check the environment variable value, allowing `KeyError` or
`ValueError` to bubble through to the caller, and only afterwards during
construction of the named pipe realize that there is no support.
</pre>

Fix coverage slipups and error messages in the Windows named pipe handles

2026-01-18T14:38:27+01:00

</pre>

Fix coverage slipup of socket provider alias registration

2026-01-18T14:25:44+01:00

When registering auto-detected new socket providers, registration should
fail if two different providers try to register the same alias.

The test suite originally contained a test case for this, but it used
the "posix" and "the_annoying_os" names as base names, which were
changed to aliases in 41029a5e6ef04a9870dcaf044b54a26af94260ab.  Thus,
the test *actually* attempted to register something that was previously
an alias as a new base name.  This was also an error (still is), and it
used the same error message, so the test continued to pass.  But it was
then exercising a different code branch, and thus the original code
branch was effectively lacking a dedicated test.

We fix this by resolving the now-aliased entry to its actual base name.
</pre>

Properly combine coverage files cross-platform

2026-01-18T14:23:57+01:00

Set the coverage settings to record relative paths, instead of absolute
ones, so that when combining coverage files from different OSes, the
paths merge cleanly.
</pre>

Use the SSH_AUTH_SOCK socket provider as "native" also on The Annoying OS

2026-01-18T14:14:04+01:00

Pageant is a good *fallback* native socket provider, but a bad
*preferred* native socket provider, because the address is not
configurable.  Using `ssh_auth_sock_on_the_annoying_os` as the preferred
native socker provider instead allows the user to easily change the
agent to talk to by switching out environment variables.
</pre>

Distinguish process-spawning heavy-duty tests from other heavy-duty tests

2026-01-17T19:40:14+01:00

Give heavy-duty tests that involve spawning processes less extensive
example counts, because spawning processes is expensive (especially on
The Annoying OS), and because Python 3.14+ is defaulting to
slow-but-safe process spawning machinery that make these costs much more
visible than before.

Specifically, we introduce new hypothesis machinery for calculating
a good `max_example` count for state machines that involve spawning
processes on each state transition.  There is currently only one such
state machine: `FakeConfigurationMutexStateMachine` from the CLI
heavy-duty tests.  The example count `n'` for state machines is then
`sqrt(10 * n)`, where `n` is the example count for other test types.
For the "dev", "default" and "intense" profiles (`n = 10`, `100` and
`1000`, respectively), this translates to `n' = 10`, `31` and `100`,
respectively.  In particular, at "dev" they are identical, and at
"intense", state machines have "default" behavior.

In preparation for this commit, we noticed that the hypothesis settings
profiles were not necessarily defined when the state machines query the
settings.  Accordingly, we moved the settings profiles setup into the
`tests.machinery.hypothesis` package, made it idempotent, and ensured it
would be called before accessing the profiles.
</pre>

Use "loadgroup" scheduling in the test suite runner

2026-01-17T19:00:49+01:00

Parallelize the test suite via the "loadgroup" scheduler, instead of the
"worksteal" scheduler.  There is currently only one `xtest_group` marker
value, so effectively, the scheduler schedules the *marked* tests all to
the same worker, and the others in whatever manner.  We can thus rely on
the marked tests executing serially, and do not need locks to protect
them (or their fixture calls) from concurrent access.

This eliminates "locking implementations" as both a source of errors and
as another group of code that needs debugging, testing, and coverage.
(Which was, unfortunately, our experience with the `filelock` package we
used to protect non-isolated SSH agents on The Annoying OS during
fixture setup and teardown.)

As a bonus, because the "loadgroup" scheduler lazily assigns work items
as other items are completed, the performance is similar to the
"worksteal" scheduler it is replacing.
</pre>

Add more coverage and linting exclusions related to Windows named pipes

2026-01-04T22:40:37+01:00

Some of the missing exclusions are typos.

Others are accidental omissions due to writing the code for one platform
(POSIX-ish systems) without actually *testing* on that platform, because
the main logic is geared towards a different platform (here, The
Annoying OS) and was developed there.  This especially concerns code
that is designed to never be called and which immediately throws an
exception upon being called: it is easy to forget the coverage exclusion
if the corresponding code path is never actually run.

Finally, other exclusions and code refactorings are due to the fact that
the static type checking interface for `ctypes` (i.e., the typing stubs
from the `typeshed` project) is vastly different for different operating
systems.  So, type checking code on POSIX-ish systems that uses `ctypes`
for The Annoying OS's facilities causes the type checker to complain
about *a lot* of undefined symbols that `ctypes` supposedly does not
expose.  For some commonly-used symbols with many call sites, it is
worth defining a dual wrapper/stub function (wrapper for supported OSes,
stub for others) to both silence the type checker's complaints about
"undefined symbols" and to not sacrifice too much readability.

(While the type checker supports branching on the current OS, this
drastically increases the number of branches to cover, or alternatively,
the number of coverage branch exceptions/exclusions to mark up.  We
would be trading type checking exclusions for coverage branch
exclusions, gaining nothing.)

Finally finally, because The Annoying OS uses a very incompatible naming
scheme in its standard library, we need many linting exceptions for
variable, function and function argument naming.
</pre>

Fix SSH agent spawning on POSIX in the test suite

2026-01-04T22:06:26+01:00

If the `executable` passed to the `spawn_named_agent` function is
`None`, we now correctly locate the agent in `PATH` using its default
name, for all our SSH agent spawning functions.  This was advertised to
work this way when we introduced SSH agent interfacing functions in the
test suite in 41029a5e6ef04a9870dcaf044b54a26af94260ab and updated the
`spawn_named_agent` signature to match in
6340b5a541970c9d00ee653926102657028de309, but was never actually
implemented, until now.

Prior to 6340b5a541970c9d00ee653926102657028de309, the `executable`
argument to `spawn_named_agent` was both a registry key and the basename
of the executable to call, to be located in `PATH`.  In that scheme,
a `None` value meant that there was no external executable to spawn, so
the agent-specific spawning functions would return a failure code.  In
6340b5a541970c9d00ee653926102657028de309, the interpretation was changed
to an "override" path: a string value for `executable` meant "use this
path for the executable", a `None` value meant "use the default name,
and locate the executable in `PATH`".  But the corresponding *logic* for
the `None` value case, i.e., searching `PATH`, was never actually
implemented.

Because none of the standard agent spawning/interfacing function
definitions made use of this override mechanism, all SSH agent spawning
functions were silently breaking, flatly claiming that the agents were
not available even though they actually might have been.  Furthermore,
because this code refactoring was developed on The Annoying OS, where
all current SSH agents are interfaced, not spawned, this failure went
completely unnoticed.  Now, while double-checking that the new
Annoying-OS-specific code also works on POSIX, this misbehavior of the
SSH agent spawning logic became apparent again, because on POSIX we *do*
have agents that are spawned, not merely interfaced.

So reintroduce the logic to locate the (default) executable if the path
is not overriden.
</pre>