fish: Add fishEnvPreInit option

This new option allows for replacing the sourcing of
/etc/fish/nixos-env-preinit.fish with another file, optionally passing
it through `fenv`. The idea here is that non-NixOS users can do
something like

    fish.override {
      fishEnvPreInit = sourceBash:
        sourceBash "${nix}/etc/profile.d/nix-daemon.sh";
    }

and this will set up their shell environment for Nix just as though they
were running NixOS.
This commit is contained in:
Lily Ballard 2021-02-04 16:26:53 -08:00 committed by Cole Helbling
parent dca20136ca
commit c4f980a063

View file

@ -16,11 +16,21 @@
, ncurses
, python3
, cmake
, fishPlugins
, runCommand
, writeText
, nixosTests
, useOperatingSystemEtc ? true
# An optional string containing Fish code that initializes the environment.
# This is run at the very beginning of initialization. If it sets $NIX_PROFILES
# then Fish will use that to configure its function, completion, and conf.d paths.
# For example:
# fishEnvPreInit = "source /etc/fish/my-env-preinit.fish";
# It can also be a function that takes one argument, which is a function that
# takes a path to a bash file and converts it to fish. For example:
# fishEnvPreInit = source: source "${nix}/etc/profile.d/nix-daemon.sh";
, fishEnvPreInit ? null
}:
let
etcConfigAppendix = writeText "config.fish.appendix" ''
@ -62,8 +72,12 @@ let
# 2. Before the shell is initialized, so that config snippets can find the commands they use on the PATH
builtin status --is-login
or test -z "$__fish_nixos_env_preinit_sourced" -a -z "$ETC_PROFILE_SOURCED" -a -z "$ETC_ZSHENV_SOURCED"
${if fishEnvPreInit != null then ''
and begin
${lib.removeSuffix "\n" (if lib.isFunction fishEnvPreInit then fishEnvPreInit sourceWithFenv else fishEnvPreInit)}
end'' else ''
and test -f /etc/fish/nixos-env-preinit.fish
and source /etc/fish/nixos-env-preinit.fish
and source /etc/fish/nixos-env-preinit.fish''}
and set -gx __fish_nixos_env_preinit_sourced 1
test -n "$NIX_PROFILES"
@ -94,6 +108,22 @@ let
end
'';
# This is wrapped in begin/end in case the user wants to apply redirections.
# This does mean the basic usage of sourcing a single file will produce
# `begin; begin; …; end; end` but that's ok.
sourceWithFenv = path: ''
begin # fenv
# This happens before $__fish_datadir/config.fish sets fish_function_path, so it is currently
# unset. We set it and then completely erase it, leaving its configuration to $__fish_datadir/config.fish
set fish_function_path ${fishPlugins.foreign-env}/share/fish/vendor_functions.d $__fish_datadir/functions
fenv source ${lib.escapeShellArg path}
set -l fenv_status $status
# clear fish_function_path so that it will be correctly set when we return to $__fish_datadir/config.fish
set -e fish_function_path
test $fenv_status -eq 0
end # fenv
'';
fish = stdenv.mkDerivation rec {
pname = "fish";
version = "3.1.2";