Querying all substitutable paths via "nix-env -qas" is potentially
hard on a server, since it involves sending thousands of HEAD
requests. So a binary cache must now have a meta-info file named
"nix-cache-info" that specifies whether the server wants this. It
also specifies the store prefix so that we don't send useless queries
to a binary cache for a different store prefix.
Since SubstitutionGoal::finished() in build.cc computes the hash
anyway, we can prevent the inefficiency of computing the hash twice by
letting the substituter tell Nix about the expected hash, which can
then verify it.
"nix-channel --add" now accepts a second argument: the channel name.
This allows channels to have a nicer name than (say) nixpkgs_unstable.
If no name is given, it defaults to the last component of the URL
(with "-unstable" or "-stable" removed).
Also, channels are now stored in a profile
(/nix/var/nix/profiles/per-user/$USER/channels). One advantage of
this is that it allows rollbacks (e.g. if "nix-channel --update" gives
an undesirable update).
Ensuring that the tests work from the build tree requires a growing
number of nasty hacks. The tests also don't verify that the installed
Nix actually works. Thus, the tests now require "make install" to
have been run.
Nix now requires SQLite and bzip2 to be pre-installed. SQLite is
detected using pkg-config. We required DBD::SQLite anyway, so
depending on SQLite is not a big problem.
The --with-bzip2, --with-openssl and --with-sqlite flags are gone.
other simplifications.
* Use <nix/...> to locate the corepkgs. This allows them to be
overriden through $NIX_PATH.
* Use bash's pipefail option in the NAR builder so that we don't need
to create a temporary file.
directory
/home/eelco/src/stdenv-updates
that you want to use as the directory for import such as
with (import <nixpkgs> { });
then you can say
$ nix-build -I nixpkgs=/home/eelco/src/stdenv-updates
brackets, e.g.
import <nixpkgs/pkgs/lib>
are resolved by looking them up relative to the elements listed in
the search path. This allows us to get rid of hacks like
import "${builtins.getEnv "NIXPKGS_ALL"}/pkgs/lib"
The search path can be specified through the ‘-I’ command-line flag
and through the colon-separated ‘NIX_PATH’ environment variable,
e.g.,
$ nix-build -I /etc/nixos ...
If a file is not found in the search path, an error message is
lazily thrown.
the hook every time we want to ask whether we can run a remote build
(which can be very often), we now reuse a hook process for answering
those queries until it accepts a build. So if there are N
derivations to be built, at most N hooks will be started.
The /bin/sh interpreter on Solaris doesn't understand $(...) syntax for running
sub-shells. Consequently, this test fails on Solaris. To remedy the situation,
the script either needs to be run by /bin/bash -- which is non-standard --, or
it needs to use the ancient but portable `...` syntax.
check' now succeeds :-)
* An attribute set such as `{ foo = { enable = true; };
foo.port = 23; }' now parses. It was previously rejected, but I'm
too lazy to implement the check. (The only reason to reject it is
that the reverse, `{ foo.port = 23; foo = { enable = true; }; }', is
rejected, which is kind of ugly.)
* src/libexpr/expr-to-xml.cc (nix::showAttrs): Add `location'
parameter. Provide location XML attributes when it's true. Update
callers.
(nix::printTermAsXML): Likewise.
* src/libexpr/expr-to-xml.hh (nix::printTermAsXML): Update prototype;
have `location' default to `false'.
* src/nix-instantiate/nix-instantiate.cc (printResult, processExpr): Add
`location' parameter; update callers.
(run): Add support for `--no-location'.
* src/nix-instantiate/help.txt: Update accordingly.
* tests/lang.sh: Invoke `nix-instantiate' with `--no-location' for the
XML tests.
* tests/lang/eval-okay-toxml.exp, tests/lang/eval-okay-to-xml.nix: New
files.
allowed. So `name1@name2', `{attrs1}@{attrs2}' and so on are now no
longer legal. This is no big loss because they were not useful
anyway.
This also changes the output of builtins.toXML for @-patterns
slightly.
doesn't exist. The Debian packages don't include the manifests
directory, so nix-channel would silently skip doing a nix-pull,
resulting in everything being built from source. Thanks to Juan
Pedro Bolívar Puente.
intersectAttrs returns the (right-biased) intersection between two
attribute sets, e.g. every attribute from the second set that also
exists in the first. functionArgs returns the set of attributes
expected by a function.
The main goal of these is to allow the elimination of most of
all-packages.nix. Most package instantiations in all-packages.nix
have this form:
foo = import ./foo.nix {
inherit a b c;
};
With intersectAttrs and functionArgs, this can be written as:
foo = callPackage (import ./foo.nix) { };
where
callPackage = f: args:
f ((builtins.intersectAttrs (builtins.functionArgs f) pkgs) // args);
I.e., foo.nix is called with all attributes from "pkgs" that it
actually needs (e.g., pkgs.a, pkgs.b and pkgs.c). (callPackage can
do any other generic package-level stuff we might want, such as
applying makeOverridable.) Of course, the automatically supplied
arguments can be overriden if needed, e.g.
foo = callPackage (import ./foo.nix) {
c = c_version_2;
};
but for the vast majority of packages, this won't be needed.
The advantages are to reduce the amount of typing needed to add a
dependency (from three sites to two), and to reduce the number of
trivial commits to all-packages.nix. For the former, there have
been two previous attempts:
- Use "args: with args;" in the package's function definition.
This however obscures the actual expected arguments of a
function, which is very bad.
- Use "{ arg1, arg2, ... }:" in the package's function definition
(i.e. use the ellipis "..." to allow arbitrary additional
arguments), and then call the function with all of "pkgs" as an
argument. But this inhibits error detection if you call it with
an misspelled (or obsolete) argument.
