nixpkgs/lib/filesystem.nix

46 lines
1.8 KiB
Nix
Raw Normal View History

Convert libs to a fixed-point This does break the API of being able to import any lib file and get its libs, however I'm not sure people did this. I made this while exploring being able to swap out docFn with a stub in #2305, to avoid functor performance problems. I don't know if that is going to move forward (or if it is a problem or not,) but after doing all this work figured I'd put it up anyway :) Two notable advantages to this approach: 1. when a lib inherits another lib's functions, it doesn't automatically get put in to the scope of lib 2. when a lib implements a new obscure functions, it doesn't automatically get put in to the scope of lib Using the test script (later in this commit) I got the following diff on the API: + diff master fixed-lib 11764a11765,11766 > .types.defaultFunctor > .types.defaultTypeMerge 11774a11777,11778 > .types.isOptionType > .types.isType 11781a11786 > .types.mkOptionType 11788a11794 > .types.setType 11795a11802 > .types.types This means that this commit _adds_ to the API, however I can't find a way to fix these last remaining discrepancies. At least none are _removed_. Test script (run with nix-repl in the PATH): #!/bin/sh set -eux repl() { suff=${1:-} echo "(import ./lib)$suff" \ | nix-repl 2>&1 } attrs_to_check() { repl "${1:-}" \ | tr ';' $'\n' \ | grep "\.\.\." \ | cut -d' ' -f2 \ | sed -e "s/^/${1:-}./" \ | sort } summ() { repl "${1:-}" \ | tr ' ' $'\n' \ | sort \ | uniq } deep_summ() { suff="${1:-}" depth="${2:-4}" depth=$((depth - 1)) summ "$suff" for attr in $(attrs_to_check "$suff" | grep -v "types.types"); do if [ $depth -eq 0 ]; then summ "$attr" | sed -e "s/^/$attr./" else deep_summ "$attr" "$depth" | sed -e "s/^/$attr./" fi done } ( cd nixpkgs #git add . #git commit -m "Auto-commit, sorry" || true git checkout fixed-lib deep_summ > ../fixed-lib git checkout master deep_summ > ../master ) if diff master fixed-lib; then echo "SHALLOW MATCH!" fi ( cd nixpkgs git checkout fixed-lib repl .types )
2017-07-29 02:05:35 +02:00
{ lib }:
2017-05-01 16:49:59 +02:00
{ # haskellPathsInDir : Path -> Map String Path
# A map of all haskell packages defined in the given path,
# identified by having a cabal file with the same name as the
# directory itself.
haskellPathsInDir = root:
let # Files in the root
root-files = builtins.attrNames (builtins.readDir root);
# Files with their full paths
root-files-with-paths =
map (file:
{ name = file; value = root + "/${file}"; }
) root-files;
# Subdirectories of the root with a cabal file.
cabal-subdirs =
builtins.filter ({ name, value }:
builtins.pathExists (value + "/${name}.cabal")
) root-files-with-paths;
in builtins.listToAttrs cabal-subdirs;
# locateDominatingFile : RegExp
2017-03-04 19:15:23 +01:00
# -> Path
# -> Nullable { path : Path;
# matches : [ MatchResults ];
# }
# Find the first directory containing a file matching 'pattern'
# upward from a given 'file'.
# Returns 'null' if no directories contain a file matching 'pattern'.
locateDominatingFile = pattern: file:
let go = path:
let files = builtins.attrNames (builtins.readDir path);
matches = builtins.filter (match: match != null)
(map (builtins.match pattern) files);
in
if builtins.length matches != 0
then { inherit path matches; }
else if path == /.
then null
else go (dirOf path);
parent = dirOf file;
isDir =
let base = baseNameOf file;
type = (builtins.readDir parent).${base} or null;
in file == /. || type == "directory";
in go (if isDir then file else parent);
}