Nixpkgs: TeXLive pygmentex package has a Python 2 script that does not work

[romildo]

I have installed the TeXLive pygmentex package on my system, but its binary script pygmentex.py fails to run because:

• its directory is not found in $PATH
• it does not have an explicitly dependency on python2
• it does not have an explicitly dependency on pygments
• the pygments module for Python 2 cannot be found.

Please fix this issues so that the script can be run.

(Maybe @vcunat can take a look at this.)

[nbp]

cc @vcunat

[vcunat]

Well, the first two bullets would be fixed very simply by

diff --git a/pkgs/tools/typesetting/tex/texlive-new/combine.nix b/pkgs/tools/typesetting/tex/texlive-new/combine.nix
index e69c6ec..c47659b 100644
--- a/pkgs/tools/typesetting/tex/texlive-new/combine.nix
+++ b/pkgs/tools/typesetting/tex/texlive-new/combine.nix
@@ -21,7 +21,7 @@ let
     # extra interpreters needed for shebangs, based on 2015 schemes "medium" and "tetex"
     # (omitted tk needed in pname == "epspdf", bin/epspdftk)
     pkgNeedsPython = pkg: pkg.tlType == "run" && lib.elem pkg.pname
-      [ "de-macro" "pythontex" "dviasm" "texliveonfly" ];
+      [ "de-macro" "pythontex" "dviasm" "texliveonfly" "pygmentex" ];
     pkgNeedsRuby = pkg: pkg.tlType == "run" && pkg.pname == "match-parens";
     extraInputs =
       lib.optional (lib.any pkgNeedsPython splitBin.wrong) python

but I don't yet have framework to add external python dependencies to the scripts.

[romildo]

Nothing new here?

A similar problem happens with pythontex:

$ pythontex
Traceback (most recent call last):
  File "/nix/store/clvqqknjxa0ynwn9ps2b6kc1kin75qyw-texlive-pythontex-0.13/scripts/pythontex/pythontex.py", line 50, in <module>
    import pythontex2 as pythontex
  File "/nix/store/clvqqknjxa0ynwn9ps2b6kc1kin75qyw-texlive-pythontex-0.13/scripts/pythontex/pythontex2.py", line 61, in <module>
    from pygments.styles import get_all_styles
ImportError: No module named pygments.styles

[romildo]

cc @vcunat

Maybe while a good solution is not engineered, a package for pygmentex without the TeX stuff can be added to nixpkgs. It would contain the binary with support for the needed Python dependencies.

What do you think?

[vcunat]

There aren't any true binaries, are there? It's just python scripts IIRC. But still, what you propose is probably the easiest way to resolve this somehow.

[romildo]

It is just a Python script that depends on the Pygments module.

[romildo]

My attempt at it:

diff --git a/pkgs/tools/typesetting/pygmentex/default.nix b/pkgs/tools/typesetting/pygmentex/default.nix
new file mode 100644
index 0000000..32ad097
--- /dev/null
+++ b/pkgs/tools/typesetting/pygmentex/default.nix
@@ -0,0 +1,45 @@
+{ stdenv, fetchzip, python2Packages }:
+
+python2Packages.buildPythonApplication rec {
+  name = "pygmentex-${version}";
+  version = "0.8";
+
+  src = fetchzip {
+      url = "http://mirrors.ctan.org/macros/latex/contrib/pygmentex.zip";
+      sha256 = "1nm19pvhlv51mv2sdankndhw64ys9r7ch6szzd6i4jz8zr86kn9v";
+  };
+
+  pythonPath = [ python2Packages.pygments python2Packages.chardet ];
+
+  buildPhase = ":";
+  
+  doCheck = false;
+  
+  installPhase = ''
+  
+    mkdir -p $out/bin
+    cp -a pygmentex.py $out/bin
+  '';
+
+  meta = with stdenv.lib; {
+    homepage = https://www.ctan.org/pkg/pygmentex;
+    description = "Auxiliary tool for typesetting code listings in LaTeX documents using Pygments";
+    longDescription = ''
+      PygmenTeX is a Python-based LaTeX package that can be used for
+      typesetting code listings in a LaTeX document using Pygments.
+
+      Pygments is a generic syntax highlighter for general use in all kinds of
+      software such as forum systems, wikis or other applications that need to
+      prettify source code.
+
+      This package installs just the script needed to process code listings
+      snippets extracted from the a LaTeX document by the pygmentex LaTeX
+      package. In order to use it effectivelly the texlive package pygmentex
+      also has to be installed. This can be done by adding pygmentex to
+      texlive.combine.
+    '';
+    license = licenses.lppl13;
+    maintainers = with maintainers; [ romildo ];
+    platforms = platforms.unix;
+  };
+}
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index f38ee99..8a4e27f 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -3002,6 +3002,8 @@ let

   pydb = callPackage ../development/tools/pydb { };

+  pygmentex = callPackage ../tools/typesetting/pygmentex { };
+
   pystringtemplate = callPackage ../development/python-modules/stringtemplate { };

   pythonDBus = dbus_python;

[vcunat]

So pygmentex works as expected now?

[romildo]

It works! It can be tested by downloading the example document from the distribution on CTAN, unzipping the downloaded files, removing the Python script and the LaTeX style class, and than compiling demo.tex:

$ pdflatex demo
$ pygmentex.py demo.snippets
$ pdflatex demo
$ pdflatex demo

The result is demo.pdf, with many examples of code listings typeset by Pygments.

[vcunat]

OK, then I think we can close this.

[schmittlauch]

Sorry for necromancing this (should I have opened a new issue instead?), but it doesn't "just work" @romildo – or needs further documentation on how to use it:

The pygmentex created by building the pygmentex texlive package can not find the pygments module.

nix-shell -E "with import <nixpkgs> {}; (pkgs.texlive.combine { inherit (pkgs.texlive) scheme-small pygmentex; })" gives us such an environment, just try running the pygmentex command from there -> ImportError: No module named pygments

The pkgs.pygmentex package though provides a pygmentex.py executable which works just fine and finds the needed pygments python module.

So how to combine these both packages?
In particular I ran into this when trying to use the minted texlive package, as that seems to directly invoke the pygmentex executable during build.

Issue appears on release-18.09

[timhae]

I encountered the same issue, the latex package minted seems to be working fine tough (and can be used as a replacement)

[romildo]

@schmittlauch I have in environment.systemPackages both pkgs.texlive.combine with pygmentex (which provides the style file pygmentex.sty and a non-functional pygmentex Python script, because of missing Python dependencies) and pkgs.pygmentex (which provides the pygmentex.py script). This setup works for me.

[romildo]

I still do not know a way of allowing Python module dependencies for Python scripts installed through pkgs.texlive.combine.

[veprbl]

This is to be fixed in #75730