mcomix3 nix package (WIP)

mcomix3.nix

{ stdenv
, fetchFromGitHub
, python3
, python3Packages
, wrapGAppsHook
, gobject-introspection
, gtk3
, gdk-pixbuf
# Recommended Dependencies:
, unrar
, p7zip
, lhasa
, mupdf
}:

python3Packages.buildPythonApplication rec {
  pname = "mcomix3";
  version = "20201123";

  # fetch from github because no official release on pypi/github and no build system
  src = fetchFromGitHub {
    repo   = "${pname}";
    owner  = "multiSnow";
    rev = "cdcb27533dc7ee2ebf7b0a8ab5ba10e61c0b8ff8";
    sha256 = "0q9xgl60ryf7qmy5vgzgfry4rvw5j9rb4d1ilxmpjmvm7dd3fm2k";
  };

  nativeBuildInputs = [ wrapGAppsHook ];
  propagatedBuildInputs = (with python3Packages; [ pillow pygobject3 pycairo ])
    ++ [ gobject-introspection gtk3 gdk-pixbuf ]
    ++ [ unrar p7zip lhasa mupdf ];

  format = "other";
  strictDeps = false;

  preInstall = ''
    libdir=$out/lib/${python3.libPrefix}/site-packages
    mkdir -p $out/share/{icons/hicolor,man/man1,applications,metainfo,thumbnailers}
    mkdir -p $out/bin $libdir
  '';

  installPhase = ''
    runHook preInstall

    ${python3.executable} installer.py --srcdir=mcomix --target=$libdir
    mv $libdir/mcomix/mcomixstarter.py $out/bin/mcomix3
    mv $libdir/mcomix/comicthumb.py $out/bin/comicthump
    mv $libdir/mcomix/mcomix/* $libdir/mcomix

    runHook postInstall
  '';

  postInstall = ''
    rmdir $libdir/mcomix/mcomix
    cp man/* $out/share/man/man1/
    cp -r mime/icons/* $out/share/icons/hicolor/
    cp mime/*.desktop $out/share/applications/
    cp mime/*.appdata.xml $out/share/metainfo/
    cp mime/*.thumbnailer $out/share/thumbnailers/
    for folder in $out/share/icons/hicolor/*; do
        mkdir $folder/{apps,mimetypes}
        mv $folder/*.png $folder/mimetypes
        cp $folder/mimetypes/application-x-cbt.png $folder/mimetypes/application-x-cbr.png
        cp $folder/mimetypes/application-x-cbt.png $folder/mimetypes/application-x-cbz.png
    done
  '';

  # The tests seem to be broken upstream
  #checkInputs = [ python3Packages.pytest ];
  #checkPhase = ''
  #  HOME=$TMPDIR pytest
  #'';
  doCheck = true;
  checkPhase = ''
    $out/bin/comicthump --help > /dev/null
    $out/bin/mcomix3 --help > /dev/null
  '';

  meta = with stdenv.lib; {
    description = "Comic book reader and image viewer; python3 fork of mcomix";
    longDescription = "User-friendly, customizable image viewer, specifically designed to handle comic books and manga supporting a variety of container formats (including CBR, CBZ, CB7, CBT, LHA and PDF)";
    homepage = "https://github.com/multiSnow/mcomix3";
    changelog = "https://github.com/multiSnow/mcomix3/blob/gtk3/ChangeLog";
    license = licenses.gpl2Plus;
    maintainers = with maintainers; [ confus ];
    platforms = platforms.all;
  };
}

Why not? The symlinks aren't wrapped at the end of day, like files themselves?

But the files need to be wrapped and as my understanding goes, the wrapGAppsHook only wraps files in $out/bin/ and doesn't follow symlinks to wrapp their targets. Or am I wrong?

As far as I remember, the wrapper

1. renames the file to be wrapped to something like .fancy-file-wrapped (the dot is to hide it from the listings);
2. creates a new fancy-file, containing a shell script that creates an environment (usually by setting relevant environment variables and options) and a call to .fancy-file-wrapped

What I am saying here is to create a symlink to (say) mcomixstarter.py after the wrapping, with the name mcomix3 (and the same to comicthumb), instead of renaming them.

do you have any guidelines and useful tips for me regarding my first PR to nixpkgs and the cleanup of this expression?

Well, I think I already said the most of things about it, including the cosmetical ones.

I'm trying to get the tests to work, but they might be broken upstream.

Maybe it can be a bad interaction with nixpkgs. But I don't know...