While trying to figure out how `nix-env`/`nix profile` work I had a hard
time understand how man pages were being installed.
Took me quite some time to figure this out, thought it might be useful
to others too!
A few notes:
* The `echo hi` is needed to make sure that a file that can be read by
`nix log` is properly created (i.e. some output is needed). This is
known and to be fixed in #6051.
* We explicitly ignore the floating-CA case here: the `$out` of `input3`
depends on `$out` of `input2`. This means that there are actually two
derivations - I assume that this is because at eval time (i.e.
`nix-instantiate -A`) the hash of `input2` isn't known yet and the
other .drv is created as soon as `input2` was built. This is another
issue on its own, so we ignore the case here explicitly.
diff-index operates on the view that git has of the working tree,
which might be outdated. The higher-level diff command does this
automatically. This change also adds handling for submodules.
fixes#4140
Alternative fixes would be invoking update-index before diff-index or
matching more closely what require_clean_work_tree from git-sh-setup.sh
does, but both those options make it more difficult to reason about
correctness.
The .git/refs/heads directory might be empty for a valid
usable git repository. This often happens in CI environments,
which might only fetch commits, not branches.
Therefore instead we let git itself check if HEAD points to
something that looks like a commit.
fixes#5302
To avoid that JSON messages are parsed twice in case of
remote builds with `ssh-ng://`, I split up the original
`handleJSONLogMessage` into three parts:
* `parseJSONMessage(const std::string&)` checks if it's a message in the
form of `@nix {...}` and tries to parse it (and prints an error if the
parsing fails).
* `handleJSONLogMessage(nlohmann::json&, ...)` reads the fields from the
message and passes them to the logger.
* `handleJSONLogMessage(const std::string&, ...)` behaves as before, but
uses the two functions mentioned above as implementation.
In case of `ssh-ng://`-logs the first two methods are invoked manually.
Right now when building a derivation remotely via
$ nix build -j0 -f . hello -L --builders 'ssh://builder'
it's possible later to read through the entire build-log by running
`nix log -f . hello`. This isn't possible however when using `ssh-ng`
rather than `ssh`.
The reason for that is that there are two different ways to transfer
logs in Nix through e.g. an SSH tunnel (that are used by `ssh`/`ssh-ng`
respectively):
* `ssh://` receives its logs from the fd pointing to `builderOut`. This
is directly passed to the "log-sink" (and to the logger on each `\n`),
hence `nix log` works here.
* `ssh-ng://` however expects JSON-like messages (i.e. `@nix {log data
in here}`) and passes it directly to the logger without doing anything
with the `logSink`. However it's certainly possible to extract
log-lines from this format as these have their own message-type in the
JSON payload (i.e. `resBuildLogLine`).
This is basically what I changed in this patch: if the code-path for
`builderOut` is not reached and a `logSink` is initialized, the
message was successfully processed by the JSON logger (i.e. it's in
the expected format) and the line is of the expected type (i.e.
`resBuildLogLine`), the line will be written to the log-sink as well.
Closes#5079
Allows completing `nix build ~/flake#<Tab>`.
We can implement expansion for `~user` later if needed.
Not using wordexp(3) since that expands way too much.
Fixes#6122, which reports a problem with trying to run the installer
under another user (probably: user is not the disk "owner" and thus
can't mount the volume).
This also makes sure that we get the Docker images from the same Hydra
eval, rather than the latest build from job/nix/.../dockerImage, which
may not be the same.
