1 files changed, 34 insertions, 0 deletions
diff --git a/nixpkgs/pkgs/build-support/emacs/emacs-funcs.sh b/nixpkgs/pkgs/build-support/emacs/emacs-funcs.sh
new file mode 100644
index 000000000000..e1e6a3b62208
--- /dev/null
+++ b/nixpkgs/pkgs/build-support/emacs/emacs-funcs.sh
@@ -0,0 +1,34 @@
+addToEmacsLoadPath() {
+  local lispDir="$1"
+  if [[ -d $lispDir && ${EMACSLOADPATH-} != *"$lispDir":* ]] ; then
+    # It turns out, that the trailing : is actually required
+    # see https://www.gnu.org/software/emacs/manual/html_node/elisp/Library-Search.html
+    export EMACSLOADPATH="$lispDir:${EMACSLOADPATH-}"
+  fi
+}
+
+addToEmacsNativeLoadPath() {
+  local nativeDir="$1"
+  if [[ -d $nativeDir && ${EMACSNATIVELOADPATH-} != *"$nativeDir":* ]]; then
+    export EMACSNATIVELOADPATH="$nativeDir:${EMACSNATIVELOADPATH-}"
+  fi
+}
+
+addEmacsVars () {
+  addToEmacsLoadPath "$1/share/emacs/site-lisp"
+
+  if [ -n "${addEmacsNativeLoadPath:-}" ]; then
+    addToEmacsNativeLoadPath "$1/share/emacs/native-lisp"
+  fi
+
+  # Add sub paths to the Emacs load path if it is a directory
+  # containing .el files. This is necessary to build some packages,
+  # e.g., using trivialBuild.
+  for lispDir in \
+      "$1/share/emacs/site-lisp/"* \
+      "$1/share/emacs/site-lisp/elpa/"*; do
+    if [[ -d $lispDir && "$(echo "$lispDir"/*.el)" ]] ; then
+      addToEmacsLoadPath "$lispDir"
+    fi
+  done
+}