From ca5424b750912c89afdd53869504c12e90a38a0d Mon Sep 17 00:00:00 2001
From: Dmitry Kalinkin <dmitry.kalinkin@gmail.com>
Date: Sat, 28 Nov 2020 13:17:48 -0500
Subject: [PATCH] perlPackages.LaTeXML: patch shebangs to use full path to perl
 on darwin

---
 pkgs/top-level/perl-packages.nix | 16 +++++++++-------
 1 file changed, 9 insertions(+), 7 deletions(-)

diff --git a/pkgs/top-level/perl-packages.nix b/pkgs/top-level/perl-packages.nix
index f7878f1910e..8e20d022372 100644
--- a/pkgs/top-level/perl-packages.nix
+++ b/pkgs/top-level/perl-packages.nix
@@ -10710,14 +10710,16 @@ let
       url = "mirror://cpan/authors/id/B/BR/BRMILLER/LaTeXML-0.8.4.tar.gz";
       sha256 = "92599b45fb587ac14b2ba9cc84b85d9ddc2deaf1cbdc2e89e7a6559e1fbb34cc";
     };
-    propagatedBuildInputs = [ shortenPerlShebang ArchiveZip DBFile FileWhich IOString ImageSize JSONXS LWP ParseRecDescent PodParser TextUnidecode XMLLibXSLT ];
+    propagatedBuildInputs = [ ArchiveZip DBFile FileWhich IOString ImageSize JSONXS LWP ParseRecDescent PodParser TextUnidecode XMLLibXSLT ];
     doCheck = false;  # epub test fails
-    postInstall = ''
-      shortenPerlShebang $out/bin/latexml
-      shortenPerlShebang $out/bin/latexmlc
-      shortenPerlShebang $out/bin/latexmlfind
-      shortenPerlShebang $out/bin/latexmlmath
-      shortenPerlShebang $out/bin/latexmlpost
+    nativeBuildInputs = stdenv.lib.optional stdenv.isDarwin shortenPerlShebang;
+    # shebangs need to be patched before executables are copied to $out
+    preBuild = ''
+      patchShebangs bin/
+    '' + stdenv.lib.optionalString stdenv.isDarwin ''
+      for file in bin/*; do
+        shortenPerlShebang "$file"
+      done
     '';
     meta = {
       description = "Transforms TeX and LaTeX into XML/HTML/MathML";