This commits changes the Emacs wrapper, in order to preload all autoload
definitions when built with additional packages. The list of all
definitions is generated at build-time. Packages do not need to
be (require)d for them to work.
Before this change, a code like
```sh
nix-shell -I "nixpkgs=$PWD" -p "emacs.pkgs.withPackages(e:[e.magit])" \
--run "emacs -Q -nw -f magit"
```
will fail with the message `Symbol’s function definition is void: magit`
After the change, the same code above will open Emacs with magit
enabled.
A slightly longer startup time of ~10ms was detected in local, informal
experiments.
More information on autoloading:
https://www.gnu.org/software/emacs/manual/html_node/eintr/Autoload.html
These features are internal-only, have special characters that bash
doesn't support in variable names, and aren't normally given
environment variables by cargo as far as I can tell.
This commit fixes precise dependency ignorance by converting the
environment variable `autoPatchelfIgnoreMissingDeps` into a bash array
`ignoreMissingDepsArray`, passing `"${ignoreMissingDepsArray[@]}"`
instead of `"${autoPatchelfIgnoreMissingDeps[@]}"` to the python
script.
The original implementation does not work when
`autoPatchelfIgnoreMissingDeps` contains multiple dependency names.
Because it mistakenly passes `"${autoPatchelfIgnoreMissingDeps[@]}"`
to the python script. According to the Nix manual
(https://nixos.org/manual/nix/stable/expressions/derivations.html),
lists of strings are concatenated into whitespace-separated strings,
then passed to the builder as environment variables. So, if
`autoPatchelfIgnoreMissingDeps = [ "dep1" "dep2" "dep3" ]`,
`"${autoPatchelfIgnoreMissingDeps[@]}"` will be expanded to a single
argument `"dep1 dep2 dep3"`, which is not the intended behavior,
because the python script takes the long argument as a dependency
name.
With this commit, `"${ignoreMissingDepsArray[@]}"` will be expanded to
three arguments `"dep1" "dep2" "dep3"` arguments as expected, fixing
the issue.
cpio includes the number of directory hard links in archives it creates.
Some filesystems, like btrfs, do not count directory hard links the same
way as more common filesystems like ext4 or tmpfs, so archives built
when /tmp is on such a filesystem do not reproduce. This patch replaces
cpio with bsdtar, which does not have this issue. The specific
invocation is from this page:
https://reproducible-builds.org/docs/archives/
before
$ nix build ".#whipper.tests.version"
whipper> File "/nix/store/2iiyy58pmm1ys6dy8ycbmmmfm67iakv1-whipper-0.10.0/bin/.whipper-wrapped", line 6, in <module>
whipper> File "/nix/store/2iiyy58pmm1ys6dy8ycbmmmfm67iakv1-whipper-0.10.0/lib/python3.9/site-packages/whipper/__init__.py", line 5, in <module>
note: keeping build directory '/tmp/nix-build-whipper-0.10.0-test-version.drv-7'
after
$ nix build ".#whipper.tests.version"
whipper> Traceback (most recent call last):
whipper> File "/nix/store/2iiyy58pmm1ys6dy8ycbmmmfm67iakv1-whipper-0.10.0/bin/.whipper-wrapped", line 6, in <module>
whipper> from whipper.command.main import main
whipper> File "/nix/store/2iiyy58pmm1ys6dy8ycbmmmfm67iakv1-whipper-0.10.0/lib/python3.9/site-packages/whipper/__init__.py", line 5, in <module>
whipper> from pkg_resources import (get_distribution,
whipper> ModuleNotFoundError: No module named 'pkg_resources'
note: keeping build directory '/tmp/nix-build-whipper-0.10.0-test-version.drv-34'
error: builder for '/nix/store/5lxjicdhwgmjcz9ddlxgq3s3gyaa6lz4-whipper-0.10.0-test-version.drv' failed with exit code 1;
Desktop files are only useful when accompanied by the binaries they
specify. So it makes more sense to put them next to the binaries rather
than `$out` which only usually contains the binaries.
This simplifies usages and makes the default value consistent.
In a few cases, the default value was interpreted to be `false`,
but this is useless, because virtually nobody will explicitly
set `allowAliases = true;`.
