formats.libconfig: add tests

Co-authored-by: ckie <[e-mail]>
Signed-off-by: h7x4 <[e-mail]>

pkgs/pkgs-lib/formats/libconfig/test/comprehensive/default.nix

···
+{ lib, formats, stdenvNoCC, writeText, ... }:
+let
+  libconfig = formats.libconfig { };
+
+  include_expr = {
+    val = 1;
+  };
+
+  include_file = (writeText "libconfig-test-include" ''
+    val=1;
+  '').overrideAttrs {
+    outputHashAlgo = "sha256";
+    outputHashMode = "flat";
+  };
+
+  expression = {
+    simple_top_level_attr = "1.0";
+    nested.attrset.has.a.integer.value = 100;
+    some_floaty = 29.95;
+    ## Same syntax here on these two, but they should get serialized differently:
+    # > A list may have zero or more elements, each of which can be a scalar value, an array, a group, or another list.
+    list1d = libconfig.lib.mkList [ 1 "mixed!" 5 2 ];
+    # You might also omit the mkList, as a list will be a list (in contrast to an array) by default.
+    list2d = [ 1 [ 1 1.2 "foo" ] [ "bar" 1.2 1 ] ];
+    # > An array may have zero or more elements, but the elements must all be scalar values of the same type.
+    array1d = libconfig.lib.mkArray [ 1 5 2 ];
+    array2d = [
+      (libconfig.lib.mkArray [ 1 2 ])
+      (libconfig.lib.mkArray [ 2 1 ])
+    ];
+    nasty_string = "\"@\n\\\t^*\b\f\n\0\";'''$";
+
+    weirderTypes = {
+      _includes = [ include_file ];
+      pi = 3.141592654;
+      bigint = 9223372036854775807;
+      hex = libconfig.lib.mkHex "0x1FC3";
+      octal = libconfig.lib.mkOctal "0027";
+      float = libconfig.lib.mkFloat "1.2E-3";
+      array_of_ints = libconfig.lib.mkArray [
+        (libconfig.lib.mkOctal "0732")
+        (libconfig.lib.mkHex "0xA3")
+        1234
+      ];
+      list_of_weird_types = [
+        3.141592654
+        9223372036854775807
+        (libconfig.lib.mkHex "0x1FC3")
+        (libconfig.lib.mkOctal "0027")
+        (libconfig.lib.mkFloat "1.2E-32")
+        (libconfig.lib.mkFloat "1")
+      ];
+    };
+  };
+
+  libconfig-test-cfg = libconfig.generate "libconfig-test.cfg" expression;
+in
+  stdenvNoCC.mkDerivation {
+    name = "pkgs.formats.libconfig-test-comprehensive";
+
+    dontUnpack = true;
+    dontBuild = true;
+
+    doCheck = true;
+    checkPhase = ''
+      diff -U3 ${./expected.txt} ${libconfig-test-cfg}
+    '';
+
+    installPhase = ''
+      mkdir $out
+      cp ${./expected.txt} $out/expected.txt
+      cp ${libconfig-test-cfg} $out/libconfig-test.cfg
+      cp ${libconfig-test-cfg.passthru.json} $out/libconfig-test.json
+    '';
+  }
+

pkgs/pkgs-lib/formats/libconfig/test/comprehensive/expected.txt

···
+array1d=[1, 5, 2];array2d=([1, 2], [2, 1]);list1d=(1, "mixed!", 5, 2);list2d=(1, (1, 1.2, "foo"), ("bar", 1.2, 1));nasty_string="\"@
+\\	^*bf
+0\";'''$";nested={attrset={has={a={integer={value=100;};};};};};simple_top_level_attr="1.0";some_floaty=29.95;weirderTypes={
+@include "/nix/store/jdz5yhzbbj4j77yrr7l20x1cs4kbwkj2-libconfig-test-include"
+array_of_ints=[0732, 0xa3, 1234];bigint=9223372036854775807;float=0.0012;hex=0x1fc3;list_of_weird_types=(3.141592654, 9223372036854775807, 0x1fc3, 027, 1.2e-32, 1.0);octal=027;pi=3.141592654;};
+

pkgs/pkgs-lib/formats/libconfig/test/default.nix

···
+{ pkgs, ... }:
+{
+  comprehensive = pkgs.callPackage ./comprehensive { };
+}

pkgs/pkgs-lib/tests/default.nix

···
       jdk11 = pkgs.callPackage ../formats/java-properties/test { jdk = pkgs.jdk11_headless; };
       jdk17 = pkgs.callPackage ../formats/java-properties/test { jdk = pkgs.jdk17_headless; };
     };
+    libconfig = recurseIntoAttrs (import ../formats/libconfig/test { inherit pkgs; });
   };
 
   flatten = prefix: as: