Add the Janet programming language.

[andrewchambers]

• Tested using sandboxing (nix.useSandbox on NixOS, or option sandbox in nix.conf on non-NixOS)
• Built on platform(s)
  • NixOS
  • macOS
  • other Linux distributions
• Tested via one or more NixOS test(s) if existing and applicable for the change (look inside nixos/tests)
• Tested compilation of all pkgs that depend on this change using nix-shell -p nox --run "nox-review wip"
• Tested execution of all binary files (usually in ./result/bin/)
• Determined the impact on package closure size (by running nix path-info -S before and after)
• Assured whether relevant documentation is up to date
• Fits CONTRIBUTING.md.

[veprbl]

diff --git a/pkgs/development/interpreters/janet/default.nix b/pkgs/development/interpreters/janet/default.nix
--- a/pkgs/development/interpreters/janet/default.nix
+++ b/pkgs/development/interpreters/janet/default.nix
@@ -1,4 +1,5 @@
 { stdenv, fetchFromGitHub }:
+
 stdenv.mkDerivation rec {
   name = "janet-${version}";

@@ -11,18 +12,10 @@ stdenv.mkDerivation rec {
     sha256 = "1590f1fxb6qfhf1vp2xhbvdn2jfrgipn5572cckk1ma7f13jnkpy";
   };

-  buildInputs = [ ];
-
   JANET_BUILD=''\"v${version}\"'';
+  PREFIX = placeholder "out";

-  buildPhase = ''
-    PREFIX="$out" make
-  '';
-
-  installPhase = ''
-    mkdir "$out"
-    PREFIX="$out" make install
-  '';
+  doCheck = true;

   meta = with stdenv.lib; {
     description = "Janet programming language";

[veprbl]

@GrahamcOfBorg build janet