vim-plugins: direnv-vim: hardcode the default path to direnv (#76926)

pkgs/misc/vim-plugins/overrides.nix

@@ -17,12 +17,15 @@
 # deoplete-khard dependency
 , khard
 
-# vim-go denpencies
+# vim-go dependencies
 , asmfmt, delve, errcheck, godef, golint
 , gomodifytags, gotags, gotools, go-motion
 , gnused, reftools, gogetdoc, gometalinter
 , impl, iferr, gocode, gocode-gomod, go-tools
 
+# direnv-vim dependencies
+, direnv
+
 # vCoolor dependency
 , gnome3
 }:
@@ -100,6 +103,14 @@ self: super: {
     '';
   });
 
+  direnv-vim = super.direnv-vim.overrideAttrs(oa: {
+    preFixup = oa.preFixup or "" + ''
+      substituteInPlace $out/share/vim-plugins/direnv-vim/autoload/direnv.vim \
+        --replace "let s:direnv_cmd = get(g:, 'direnv_cmd', 'direnv')" \
+          "let s:direnv_cmd = get(g:, 'direnv_cmd', '${lib.getBin direnv}/bin/direnv')"
+    '';
+  });
+
   clighter8 = super.clighter8.overrideAttrs(old: {
     preFixup = ''
       sed "/^let g:clighter8_libclang_path/s|')$|${llvmPackages.clang.cc.lib}/lib/libclang.so')|" \