From 83c59da4dae0ae2d784ce2439ad45fb6ff048741 Mon Sep 17 00:00:00 2001
From: Sean Gilligan <sean@msgilligan.com>
Date: Thu, 21 May 2026 13:07:16 -0700
Subject: [PATCH] igraph: enable (and fix) html documentation generation

Add the "html" target to the CMake build. This requires
docbook_xml_dtd_43 and docbook_xsl (catalogs) to build properly.
---
 pkgs/by-name/ig/igraph/package.nix | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/pkgs/by-name/ig/igraph/package.nix b/pkgs/by-name/ig/igraph/package.nix
index fc9e84a52608..9c9dfffaaa7d 100644
--- a/pkgs/by-name/ig/igraph/package.nix
+++ b/pkgs/by-name/ig/igraph/package.nix
@@ -12,6 +12,8 @@
   lapack,
   libxml2,
   libxslt,
+  docbook_xml_dtd_43,
+  docbook_xsl,
   llvmPackages,
   pkg-config,
   plfit,
@@ -49,6 +51,8 @@ stdenv.mkDerivation (finalAttrs: {
     flex
     libxml2
     libxslt
+    docbook_xml_dtd_43
+    docbook_xsl
     pkg-config
     python3
     sourceHighlight
@@ -83,6 +87,11 @@ stdenv.mkDerivation (finalAttrs: {
     "-DBUILD_SHARED_LIBS=ON"
   ];
 
+  buildFlags = [
+    "all"
+    "html"
+  ];
+
   doCheck = true;
 
   postInstall = ''