pkgs: add edit-managed-file script

Author: ttrssreal

flake/profiles/home/daily/pkgs.nix

@@ -60,5 +60,6 @@
     pwndbg
     kdePackages.kolourpaint
     psmisc
+    jess-scripts.edit-managed-file
   ];
 }

pkgs/default.nix

@@ -35,6 +35,7 @@
           jess-scripts = {
             nix-conf-edit = final.callPackage ./scripts/nix-conf-edit.nix { };
             nixpkgs-print-out-paths = final.callPackage ./scripts/nixpkgs-print-out-paths.nix { };
+            edit-managed-file = final.callPackage ./scripts/edit-managed-file.nix { };
           };
 
           resetti = final.callPackage ./resetti.nix { };
@@ -58,6 +59,7 @@
         inherit (pkgs.jess-scripts)
           nix-conf-edit
           nixpkgs-print-out-paths
+          edit-managed-file
           ;
       };
     };

pkgs/scripts/edit-managed-file.nix

@@ -0,0 +1,40 @@
+{
+  writeShellApplication,
+  vim,
+  ...
+}:
+writeShellApplication {
+  name = "edit-managed-file";
+
+  runtimeInputs = [
+    vim
+  ];
+
+  text = ''
+    if [ "$#" -ne 1 ]; then
+      >&2 echo "error: usage: $0 <managed-file>"
+      exit 1
+    fi
+
+    if ! [ -f "$1" ] && ! [ -h "$1" ]; then
+      >&2 echo "error: '$1' is not a file or symlink"
+      exit 1
+    fi
+
+    if ! [ -w "$1" ]; then
+      >&2 echo "error: can't edit file '$1' (do you have permissions?)"
+      exit 1
+    fi
+
+    managed_file="$(realpath --no-symlinks "$1")"
+    backup_file="''${managed_file}.orig"
+
+    >&2 echo "editing: $managed_file"
+
+    mv -v "$managed_file" "$backup_file"
+    cp -v "$backup_file" "$managed_file"
+    chmod -v +w "$managed_file"
+
+    "''${EDITOR:-vim}" "$managed_file"
+  '';
+}