python3Packages.gnucash: Build from existing gnucash package (#387100)

pkgs/by-name/gn/gnucash/0005-python-env.patch

@@ -0,0 +1,10 @@
+--- a/bindings/python/__init__.py
++++ b/bindings/python/__init__.py
+@@ -1,3 +1,7 @@
++import os
++os.environ['GNC_DBD_DIR'] = '@gnc_dbd_dir@'
++os.environ['GSETTINGS_SCHEMA_DIR'] = '@gsettings_schema_dir@'
++
+ # import all the symbols from gnucash_core, so basic gnucash stuff can be
+ # loaded with:
+ # >>> from gnucash import thingy

pkgs/by-name/gn/gnucash/package.nix

@@ -25,6 +25,8 @@
   swig,
   webkitgtk_4_0,
   wrapGAppsHook3,
+  python3,
+  replaceVars,
 }:
 
 stdenv.mkDerivation rec {
@@ -45,6 +47,11 @@ stdenv.mkDerivation rec {
     pkg-config
   ];
 
+  cmakeFlags = [
+    "-DWITH_PYTHON=\"ON\""
+    "-DPYTHON_SYSCONFIG_BUILD=\"$out\""
+  ];
+
   buildInputs =
     [
       aqbanking
@@ -63,6 +70,7 @@ stdenv.mkDerivation rec {
       libxslt
       swig
       webkitgtk_4_0
+      python3
     ]
     ++ (with perlPackages; [
       JSONParse
@@ -79,8 +87,16 @@ stdenv.mkDerivation rec {
     ./0003-remove-valgrind.patch
     # this patch makes gnucash exec the Finance::Quote wrapper directly
     ./0004-exec-fq-wrapper.patch
+    # this patch adds in env vars to the Python lib that makes it able to find required resource files
+    ./0005-python-env.patch
   ];
 
+  postPatch = ''
+    substituteInPlace bindings/python/__init__.py \
+      --subst-var-by gnc_dbd_dir "${libdbiDrivers}/lib/dbd" \
+      --subst-var-by gsettings_schema_dir ${glib.makeSchemaPath "$out" "gnucash-${version}"};
+  '';
+
   # this needs to be an environment variable and not a cmake flag to suppress
   # guile warning
   env.GUILE_AUTO_COMPILE = "0";

pkgs/top-level/python-packages.nix

@@ -5618,6 +5618,12 @@ self: super: with self; {
 
   gntp = callPackage ../development/python-modules/gntp { };
 
+  gnucash = toPythonModule (
+    pkgs.gnucash.override {
+      python3 = python;
+    }
+  );
+
   gnureadline = callPackage ../development/python-modules/gnureadline { };
 
   go2rtc-client = callPackage ../development/python-modules/go2rtc-client { };