lib/debug.nix at master · Platonic-Systems/lib · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
{ pkgs }: let
  inherit (builtins) trace toString toJSON;
  inherit (pkgs.lib.lists) head last isList length;
  inherit (pkgs.lib.trivial) runCommand warn id;
  inherit (pkgs.lib.strings) isString stringLength;
  inherit (pkgs.lib.attrsets) mapAttrs' nameValuePair filterAttrs getAttrFromPath attrNames isAttrs;

  inherit (import ./attrsets.nix { inherit pkgs; }) mapAttrVals without size;

  fns = rec {
    logFn = {
      description = ''
        Log a value after being passed through a function and yield its
        original value.
      '';
      __functor = _: f: x: trace (f x) x;
      short = "f";
    };

    log = {
      description = ''
        Log a value to stdout and yield it.
      '';
      __functor = _: logFn id;
      short = "d";
    };

    logHead = {
      description = ''
        Log the head of a list and yield the list.
      '';
      __functor = _: logFn head;
      short = "h";
    };

    logLast = {
      description = ''
        Log the last of a list and yield the list.
      '';
      __functor = _: logFn last;
      short = "l";
    };

    logLength = {
      description = ''
        Log the length of a string, list, or attribute set and yield the input.
      '';
      __functor = x: let
        f = if isList x then
          length
        else if isAttrs x then
          size
        else if isString x then
          stringLength
        else warn "logLength input is not a list, attrset, or string.";
      in logFn f x;
      short = "_";
    };

    logJSON = {
      description = ''
        Log the JSON representation of a value.
      '';
      __functor = _: logFn toJSON;
      short = "j";
    };

    logAttr = {
      description = ''
        Log the value of an attribute and yield the attrset.
      '';
      __functor = _: a: s: trace s.${a} s;
      short = "a";
    };

    logAttrPath = {
      description = ''
        Log the value of an attribute path and yield the attrset.
      '';
      __functor = _: as: s: trace (getAttrFromPath as s) s;
      short = "p";
    };

    logNames = {
      description = ''
        Log the attribute set names and yield the attrset.
      '';
      __functor = _: logFn attrNames;
      short = "n";
    };
  };
in {
  _doc = ''
    Helper functions related to debugging.
  '';
} // mapAttrVals (without "short") fns // { short = mapAttrs' (n: v: nameValuePair v.short fns.${n}) (filterAttrs (_: v: v?short) fns); }