gdb: ship a python-capable gdbinit

hosts/common/programs/assorted.nix

@@ -574,10 +574,6 @@ in
     gawk.sandbox.wrapperType = "inplace";  # /share/gawk libraries refer to /libexec
     gawk.sandbox.autodetectCliPaths = "existingFile";
 
-    gdb.sandbox.enable = false;  # gdb doesn't sandbox well. i don't know how you could.
-    # gdb.sandbox.method = "landlock";  # permission denied when trying to attach, even as root
-    gdb.sandbox.autodetectCliPaths = true;
-
     geoclue2-with-demo-agent = {};
 
     # MS GitHub stores auth token in .config

hosts/common/programs/default.nix

@@ -50,6 +50,7 @@
     ./fwupd.nix
     ./g4music.nix
     ./gajim.nix
+    ./gdb.nix
     ./gdbus.nix
     ./geary.nix
     ./git.nix

hosts/common/programs/gdb.nix

@@ -0,0 +1,13 @@
+{ pkgs, ... }:
+{
+  sane.programs.gdb = {
+    sandbox.enable = false;  # gdb doesn't sandbox well. i don't know how you could.
+    # sandbox.method = "landlock";  # permission denied when trying to attach, even as root
+    sandbox.autodetectCliPaths = true;
+    fs.".config/gdb/gdbinit".symlink.text = ''
+      # enable commands like `py-bt`, `py-list`, etc.
+      # for usage, see: <https://wiki.python.org/moin/DebuggingWithGdb>
+      source ${pkgs.python3}/share/gdb/libpython.py
+    '';
+  };
+}