Update release notes for 1.7

This commit is contained in:
Eelco Dolstra 2014-03-12 13:58:06 +01:00
parent 25386e5edc
commit e9934bb5ad

View file

@ -9,26 +9,228 @@
<section xml:id="ssec-relnotes-1.7"><title>Release 1.7 (TBA)</title>
<para>This release has the following changes:</para>
<para>In addition to the usual bug fixes, this release has the
following new features:</para>
<itemizedlist>
<listitem>
<para>Antiquotation is now allowed inside of quoted attribute
names (e.g. <literal>set."${foo}"</literal>). In the case where
the attribute name is just a single antiquotation, the quotes can
be dropped (e.g. the above example can be written
<literal>set.${foo}</literal>). If an attribute name inside of a
set declaration evaluates to <literal>null</literal> (e.g.
<literal>{ ${null} = false; }</literal>), then that attribute is
not added to the set.</para>
</listitem>
<listitem>
<para>Experimental support for cryptographically signed binary
caches. See <link
xlink:href="https://github.com/NixOS/nix/commit/0fdf4da0e979f992db75cc17376e455ddc5a96d8">the
commit for details</link>.</para>
</listitem>
<listitem>
<para>An experimental new substituter,
<command>download-via-ssh</command>, that fetches binaries from
remote machines via SSH. Specifying the flags <literal>--option
use-ssh-substituter true --option ssh-substituter-hosts
<replaceable>user@hostname</replaceable></literal> will cause Nix
to download binaries from the specified machine, if it has
them.</para>
</listitem>
<listitem>
<para><command>nix-store -r</command> and
<command>nix-build</command> have a new flag,
<option>--check</option>, that builds a previously built
derivation again, and prints an error message if the output is not
exactly the same. This helps to verify whether a derivation is
truly deterministic. For example:
<screen>
$ nix-build '&lt;nixpkgs>' -A patchelf
<replaceable></replaceable>
$ nix-build '&lt;nixpkgs>' -A patchelf --check
<replaceable></replaceable>
error: derivation `/nix/store/1ipvxs…-patchelf-0.6' may not be deterministic:
hash mismatch in output `/nix/store/4pc1dm…-patchelf-0.6.drv'
</screen>
</para>
</listitem>
<listitem>
<para>The <command>nix-instantiate</command> flags
<option>--eval-only</option> and <option>--parse-only</option>
have been renamed to <option>--eval</option> and
<option>--parse</option>, respectively.</para>
</listitem>
<listitem>
<para><command>nix-instantiate</command>,
<command>nix-build</command> and <command>nix-shell</command> now
have a flag <option>--expr</option> (or <option>-E</option>) that
allows you to specify the expression to be evaluated as a command
line argument. For instance, <literal>nix-instantiate --eval -E
'1 + 2'</literal> will print <literal>3</literal>.</para>
</listitem>
<listitem>
<para><command>nix-shell</command> improvements:</para>
<itemizedlist>
<listitem>
<para>It has a new flag, <option>--packages</option> (or
<option>-p</option>), that sets up a build environment
containing the specified packages from Nixpkgs. For example,
the command
<screen>
$ nix-shell -p sqlite xorg.libX11 hello
</screen>
will start a shell in which the given packages are
present.</para>
</listitem>
<listitem>
<para>It now uses <filename>shell.nix</filename> as the
default expression, falling back to
<filename>default.nix</filename> if the former doesnt
exist. This makes it convenient to have a
<filename>shell.nix</filename> in your project to set up a
nice development environment.</para>
</listitem>
<listitem>
<para>It evaluates the derivation attribute
<varname>shellHook</varname>, if set. Since
<literal>stdenv</literal> does not normally execute this hook,
it allows you to do <command>nix-shell</command>-specific
setup.</para>
</listitem>
<listitem>
<para>It preserves the users timezone setting.</para>
</listitem>
</itemizedlist>
</listitem>
<listitem>
<para>In chroots, Nix now sets up a <filename>/dev</filename>
containing only a minimal set of devices (such as
<filename>/dev/null</filename>). Note that it only does this if
you <emphasis>dont</emphasis> have <filename>/dev</filename>
listed in your <option>build-chroot-dirs</option> setting;
otherwise, it will bind-mount the <literal>/dev</literal> from
outside the chroot.</para>
<para>Similarly, if you dont have <filename>/dev/pts</filename> listed
in <option>build-chroot-dirs</option>, Nix will mount a private
<literal>devpts</literal> filesystem on the chroots
<filename>/dev/pts</filename>.</para>
</listitem>
<listitem>
<para>New built-in function: <function>builtins.toJSON</function>,
which returns a JSON representation of a value.</para>
</listitem>
<listitem><para><command>nix-setuid-helper</command> is
gone.</para></listitem>
<listitem>
<para><command>nix-env -q</command> has a new flag
<option>--json</option> to print a JSON representation of the
installed or available packages.</para>
</listitem>
<listitem><para>Now antiquotation is allowed inside of quoted
attribute names (e.g. <literal>set."${foo}"</literal>). In the
case where the attribute name is just a single antiquotation,
the quotes can be dropped (e.g. the above example can be written
<literal>set.${foo}</literal>). If an attribute name inside of a
set declaration evaluates to <literal>null</literal> (e.g.
<literal>{ ${null} = false; }</literal>), then that attribute is not
added to the set.</para></listitem>
<listitem>
<para><command>nix-env</command> now supports meta attributes with
more complex values, such as attribute sets.</para>
</listitem>
<listitem>
<para>The <option>-A</option> flag now allows attribute names with
dots in them, e.g.
<screen>
$ nix-instantiate --eval '&lt;nixos>' -A 'config.systemd.units."nscd.service".text'
</screen>
</para>
</listitem>
<listitem>
<para>The <option>--max-freed</option> option to
<command>nix-store --gc</command> now accepts a unit
specifier. For example, <literal>nix-store --gc --max-freed
1G</literal> will free up to 1 gigabyte of disk space.</para>
</listitem>
<listitem>
<para>Nix now heuristically detects whether a build failure was
due to a disk-full condition. In that case, the build is not
flagged as “permanently failed”. This is mostly useful for Hydra,
which needs to distinguish between permanent and transient build
failures.</para>
</listitem>
<listitem>
<para>There is a new symbol <literal>__curPos</literal> that
expands to an attribute set containing its file name and line and
column numbers, e.g. <literal>{ file = "foo.nix"; line = 10;
column = 5; }</literal>. There also is a new builtin function,
<varname>unsafeGetAttrPos</varname>, that returns the position of
an attribute. This is used by Nixpkgs to provide location
information in error messages, e.g.
<screen>
$ nix-build '&lt;nixpkgs>' -A libreoffice --argstr system x86_64-darwin
error: the package libreoffice-4.0.5.2 in .../applications/office/libreoffice/default.nix:263
is not supported on x86_64-darwin
</screen>
</para>
</listitem>
<listitem>
<para>The garbage collector is now more concurrent with other Nix
processes because it releases certain locks earlier.</para>
</listitem>
<listitem>
<para>The binary tarball installer has been improved. You can now
install Nix by running:
<screen>
$ bash &lt;(curl https://nixos.org/nix/install)
</screen>
</para>
</listitem>
<listitem>
<para>The command <command>nix-setuid-helper</command> is
gone.</para>
</listitem>
<listitem>
<para>Nix no longer uses Automake, but instead has a
non-recursive, GNU Make-based build system.</para>
</listitem>
<listitem>
<para>All installed libraries now have the prefix
<literal>libnix</literal>. In particular, this gets rid of
<literal>libutil</literal>, which could clash with libraries with
the same name from other packages.</para>
</listitem>
</itemizedlist>
@ -606,7 +808,7 @@ Friesdorf, Mats Erik Andersson and Shea Levy.</para>
<para>When using the Nix daemon, the <option>-s</option> flag in
<command>nix-env -qa</command> is now much faster.</para>
</listitem>
</itemizedlist>
</section>
@ -636,7 +838,7 @@ previous release. Here are the most significant:</para>
<filename>/nix/var/nix/manifests</filename>, resulting in a
significant speedup.</para>
</listitem>
<listitem>
<para>Nix now has an search path for expressions. The search path
is set using the environment variable <envar>NIX_PATH</envar> and
@ -673,7 +875,7 @@ previous release. Here are the most significant:</para>
you can write <literal>{ "foo-1.2" = …; "bla bla" = …; }."bla
bla"</literal>.</para>
</listitem>
<listitem>
<para>Attribute selection can now provide a default value using
the <literal>or</literal> operator. For instance, the expression
@ -872,7 +1074,7 @@ features:</para>
</programlisting>
This is useful, for instance, in NixOS configuration files.</para>
</listitem>
<listitem>
@ -889,7 +1091,7 @@ features:</para>
which causes <command>uname</command> to return
<literal>i686</literal> in child processes.</para>
</listitem>
<listitem>
<para>Various improvements to the <literal>chroot</literal>
support. Building in a <literal>chroot</literal> works quite well
@ -906,12 +1108,12 @@ features:</para>
<listitem>
<para>Support for large (> 4 GiB) files in NAR archives.</para>
</listitem>
<listitem>
<para>Various (performance) improvements to the remote build
mechanism.</para>
</listitem>
<listitem>
<para>New primops: <varname>builtins.addErrorContext</varname> (to
add a string to stack traces — useful for debugging),
@ -1050,8 +1252,8 @@ the following derivations will be built:
the following paths will be downloaded/copied (30.02 MiB):
/nix/store/4m8pvgy2dcjgppf5b4cj5l6wyshjhalj-samba-3.2.4
/nix/store/7h1kwcj29ip8vk26rhmx6bfjraxp0g4l-libunwind-0.98.6
...</screen>
...</screen>
</para></listitem>
<listitem><para>Language features:
@ -1091,7 +1293,7 @@ the following paths will be downloaded/copied (30.02 MiB):
division).
<!-- <varname>builtins.genericClosure</varname> -->
</para></listitem>
</itemizedlist>
</para></listitem>
@ -1162,7 +1364,7 @@ on Nix. Here is an (incomplete) list:</para>
<literal>nix-env -p /nix/var/nix/profiles/browser --set
firefox</literal> lets the profile named
<filename>browser</filename> contain just Firefox.</para></listitem>
<listitem><para><command>nix-env</command> now maintains
meta-information about installed packages in profiles. The
@ -1171,7 +1373,7 @@ on Nix. Here is an (incomplete) list:</para>
<varname>homepage</varname>. The command <literal>nix-env -q --xml
--meta</literal> shows all meta-information.</para></listitem>
<listitem><para><command>nix-env</command> now uses the
<varname>meta.priority</varname> attribute of derivations to resolve
filename collisions between packages. Lower priority values denote
@ -1227,7 +1429,7 @@ on Nix. Here is an (incomplete) list:</para>
</para></listitem>
<listitem><para><command>nix-env -q</command> now has a flag
<option>--prebuilt-only</option> (<option>-b</option>) that causes
<command>nix-env</command> to show only those derivations whose
@ -1238,7 +1440,7 @@ on Nix. Here is an (incomplete) list:</para>
<command>nix-env -i</command> and <command>nix-env -u</command> to
filter out derivations for which no pre-built binary is
available.</para></listitem>
<listitem><para>The new option <option>--argstr</option> (in
<command>nix-env</command>, <command>nix-instantiate</command> and
@ -1254,7 +1456,7 @@ on Nix. Here is an (incomplete) list:</para>
<parameter>paths</parameter> that shows the build log of the given
paths.</para></listitem>
<!--
<listitem><para>TODO: semantic cleanups of string concatenation
etc. (mostly in r6740).</para></listitem>
@ -1312,12 +1514,12 @@ on Nix. Here is an (incomplete) list:</para>
<literal>md5</literal>. You can pass either a hexadecimal or a
base-32 encoding of the hash.</para></listitem>
<listitem><para>Nix can now perform builds in an automatically
generated “chroot”. This prevents a builder from accessing stuff
outside of the Nix store, and thus helps ensure purity. This is an
experimental feature.</para></listitem>
<listitem><para>The new command <command>nix-store
--optimise</command> reduces Nix store disk space usage by finding
@ -1325,7 +1527,7 @@ on Nix. Here is an (incomplete) list:</para>
It typically reduces the size of the store by something like
25-35%.</para></listitem>
<listitem><para><filename>~/.nix-defexpr</filename> can now be a
directory, in which case the Nix expressions in that directory are
combined into an attribute set, with the file names used as the
@ -1411,10 +1613,10 @@ irreversible.</para></warning>
<itemizedlist>
<!-- Usability / features -->
<listitem><para><command>nix-env</command> usability improvements:
<itemizedlist>
@ -1450,9 +1652,9 @@ irreversible.</para></warning>
most packages in Nixpkgs dont have yet).</para></listitem>
</itemizedlist>
</para></listitem>
<listitem><para>New language features:
@ -1475,7 +1677,7 @@ irreversible.</para></warning>
You can write arbitrary expressions within
<literal>${<replaceable>...</replaceable>}</literal>, not just
identifiers.</para></listitem>
<listitem><para>Multi-line string literals.</para></listitem>
<listitem><para>String concatenations can now involve
@ -1517,7 +1719,7 @@ irreversible.</para></warning>
Very convenient whenever you have some package on your machine and
you want to copy it somewhere else.</para></listitem>
<listitem><para>XML support:
<itemizedlist>
@ -1540,7 +1742,7 @@ irreversible.</para></warning>
</itemizedlist>
</para></listitem>
<listitem><para>You can now unambiguously specify which derivation to
build or install in <command>nix-env</command>,
@ -1554,7 +1756,7 @@ irreversible.</para></warning>
<replaceable>foo</replaceable></literal>. <literal>nix-env -q
--attr</literal> shows the attribute names corresponding to each
derivation.</para></listitem>
<listitem><para>If the top-level Nix expression used by
<command>nix-env</command>, <command>nix-instantiate</command> or
@ -1565,7 +1767,7 @@ irreversible.</para></warning>
<replaceable>value</replaceable></option> can be used to specify
function arguments on the command line.</para></listitem>
<listitem><para><literal>nix-install-package --url
<replaceable>URL</replaceable></literal> allows a package to be
installed directly from the given URL.</para></listitem>
@ -1611,7 +1813,7 @@ irreversible.</para></warning>
</para></listitem>
<listitem><para>Garbage collector improvements:
<itemizedlist>
@ -1643,12 +1845,12 @@ irreversible.</para></warning>
from the Nix store. It wont delete reachable (non-garbage)
paths unless <option>--ignore-liveness</option> is
specified.</para></listitem>
</itemizedlist>
</para></listitem>
<listitem><para>Berkeley DB 4.4s process registry feature is used
to recover from crashed Nix processes.</para></listitem>
@ -1814,7 +2016,7 @@ svnService = derivation {
};</programlisting>
Previously, this would yield a black hole (infinite recursion).</para>
</listitem>
<listitem><para><command>nix-build</command> now defaults to using
@ -1956,7 +2158,7 @@ $ nix-store -q --referrers-closure \
/nix/store/8lz9yc6zgmc0vlqmn2ipcpkjlmbi51vv-glibc-2.3.4</screen>
</para>
</listitem>
<listitem><para>The concept of fixed-output derivations has been
@ -2220,7 +2422,7 @@ $ nix-env -f .../i686-linux.nix -i -E 'x: x.firefoxWrapper'</screen>
columnised).</para></listitem>
</itemizedlist>
</para>
</listitem>
@ -2234,7 +2436,7 @@ $ nix-env -f .../i686-linux.nix -i -E 'x: x.firefoxWrapper'</screen>
<para>Nix expression language changes:
<itemizedlist>
<listitem><para>New language construct: <literal>with
<replaceable>E1</replaceable>;
<replaceable>E2</replaceable></literal> brings all attributes