bins/gen-patches: initial script to help generate patches for nixpkgs

bins/default.nix

@@ -13,10 +13,12 @@ let
     inherit gosignify;
     inherit (pkgs) curl;
   });
+  genPatches = import ./gen-patches.nix { inherit pkgs; };
 
 in {
   environment.systemPackages = with pkgs; [
     checkRestart
+    genPatches
     ix
     sfetch
     tstart

bins/gen-patches.nix

@@ -0,0 +1,50 @@
+{ writeShellApplication, diffutils, findutils, coreutils, ... }:
+
+let
+  genPatches = writeShellApplication {
+    name = "gen-patches";
+    runtimeInputs = [ diffutils findutils coreutils ];
+    text = ''
+      suffix=".orig"
+      srcdir=$PWD
+      output="$PWD/patches"
+
+      usage() {
+        echo "Usage: $0 [-s suffix (default .orig)] [-d source directory (default PWD)] [-o output directory (default PWD/patches)]" 1>&2;
+        exit 1;
+      }
+
+      while getopts "d:ho:s:" arg; do
+        case $arg in
+          d)
+            srcdir=$OPTARG
+            ;;
+          h)
+            usage
+            ;;
+          s)
+            suffix=$OPTARG
+            ;;
+          o)
+            output=$OPTARG
+            ;;
+          *)
+            usage
+        esac
+      done
+
+      mkdir -p "$output"
+
+      # hold my be er!
+      # shellcheck disable=SC2044
+      for patch in $(find "$srcdir" -name "*$suffix"); do
+        fname=$(basename "$patch" "$suffix")
+        dname=$(dirname "$patch")
+        file="$dname/$fname"
+        outfile=$(echo "$dname/$fname" | sed 's;/;_;g')
+        diff -u "$file" "$patch" > "$output/$outfile";
+        echo "==> Created patch: $output/$outfile"
+      done
+    '';
+  };
+in genPatches