core/pkgs/by-name/py/python/wrap-python.nix
2024-06-30 09:16:52 +01:00

67 lines
2 KiB
Nix

{
lib,
python,
makePythonHook,
makeWrapper,
}:
makePythonHook {
name = "wrap-python-hook";
propagatedBuildInputs = [ makeWrapper ];
substitutions.sitePackages = python.sitePackages;
substitutions.executable = python.interpreter;
substitutions.python = python.pythonOnBuildForHost;
substitutions.pythonHost = python;
substitutions.magicalSedExpression =
let
# Looks weird? Of course, it's between single quoted shell strings.
# NOTE: Order DOES matter here, so single character quotes need to be
# at the last position.
quoteVariants = [
"'\"'''\"'"
"\"\"\""
"\""
"'\"'\"'"
]; # hey Vim: ''
mkStringSkipper =
labelNum: quote:
let
label = "q${toString labelNum}";
isSingle = lib.elem quote [
"\""
"'\"'\"'"
];
endQuote = if isSingle then "[^\\\\]${quote}" else quote;
in
''
/^[a-z]?${quote}/ {
/${quote}${quote}|${quote}.*${endQuote}/{n;br}
:${label}; n; /^${quote}/{n;br}; /${endQuote}/{n;br}; b${label}
}
'';
# This preamble does two things:
# * Sets argv[0] to the original application's name; otherwise it would be .foo-wrapped.
# Python doesn't support `exec -a`.
# * Adds all required libraries to sys.path via `site.addsitedir`. It also handles *.pth files.
preamble = ''
import sys
import site
import functools
sys.argv[0] = '"'$(readlink -f "$f")'"'
functools.reduce(lambda k, p: site.addsitedir(p, k), ['"$([ -n "$program_PYTHONPATH" ] && (echo "'$program_PYTHONPATH'" | sed "s|:|','|g") || true)"'], site._init_pathinfo())
'';
in
''
1 {
:r
/\\$|,$/{N;br}
/__future__|^ |^ *(#.*)?$/{n;br}
${lib.concatImapStrings mkStringSkipper quoteVariants}
/^[^# ]/i ${lib.replaceStrings [ "\n" ] [ ";" ] preamble}
}
'';
} ./wrap.sh