cleanup: remove XDG_SESSION_TYPE, XDG_VTNR from global environment

hosts/common/programs/komikku.nix

@@ -1,14 +1,14 @@
 { pkgs, ... }:
 {
   sane.programs.komikku = {
-    # packageUnwrapped = pkgs.komikku.overrideAttrs (upstream: {
-    #   preFixup = ''
-    #     # 2024/02/21: render bug which affects only moby:
-    #     #             large images render blank in several gtk applications.
-    #     #             may resolve itself as gtk or mesa are updated.
-    #     gappsWrapperArgs+=(--set GSK_RENDERER cairo)
-    #   '' + (upstream.preFixup or "");
-    # });
+    packageUnwrapped = pkgs.komikku.overrideAttrs (upstream: {
+      preFixup = ''
+        # 2024/07/25: Komikku uses XDG_SESSION_TYPE in the webkitgtk useragent, and errors if it's empty.
+        #             XDG_SESSION_DESKTOP is used similarly in debug_info.py.
+        #             TODO: patch/upstream Komikku
+        gappsWrapperArgs+=(--set-default XDG_SESSION_TYPE "unknown" --set-default XDG_SESSION_DESKTOP "unknown")
+      '' + (upstream.preFixup or "");
+    });
 
     sandbox.method = "bwrap";  # TODO:sandbox untested
     sandbox.net = "clearnet";

hosts/common/programs/sway/default.nix

@@ -13,6 +13,19 @@ let
         echo "warning: required directory not found (create it?): $(dirname "$XDG_RUNTIME_DIR/$WAYLAND_DISPLAY")"
       test -e /tmp/.X11-unix || \
         echo "warning: required directory not found (create it?): /tmp/.X11-unix"
+
+      # sway needs to know which virtual TTY to render to
+      setVtnr() {
+        local ttyPath="$(tty)"
+        case $ttyPath in
+          (/dev/tty*)
+            export XDG_VTNR=''${ttyPath#/dev/tty}
+            ;;
+        esac
+      }
+      if ! [ -v "$XDG_VTNR" ]; then
+        setVtnr
+      fi
       # delete DISPLAY-related vars from env before launch, else sway will try to connect to a remote display.
       # (consider: nested sway sessions, where sway actually has a reason to read these)
       exec env -u DISPLAY -u WAYLAND_DISPLAY "DESIRED_WAYLAND_DISPLAY=$WAYLAND_DISPLAY" ${configuredSway}/bin/sway 2>&1

modules/users/default.nix

@@ -201,9 +201,12 @@ let
         #   - doesn't have to be numeric, could be "colin"
         # - XDG_SESSION_CLASS
         #   - e.g. "user"
+        # - XDG_SESSION_DESKTOP
+        #   - e.g. "Phosh"
         # - XDG_SESSION_TYPE
         #   - e.g. "tty", "wayland"
         # - XDG_VTNR
+        #   - e.g. `1`, or `2`. corresponds to some /dev/ttyN.
         # - SYSTEMD_EXEC_PID
         # some of my program-specific environment variables depend on some of these being set,
         # hence do that early:
@@ -247,34 +250,17 @@ let
               done
             }
 
-            setVTNR() {
-              # some desktops (e.g. sway) need to know which virtual TTY to render to
-              if [ -v "$XDG_VTNR" ]; then
-                return
-              fi
-              local ttyPath=$(tty)
-              case $ttyPath in
-                (/dev/tty*)
-                  export XDG_VTNR=''${ttyPath#/dev/tty}
-                  ;;
-              esac
-            }
-            sessionCommands+=('setVTNR')
-            setXdgSessionType() {
-              # some apps (e.g. Komikku) require XDG_SESSION_TYPE to be set
-              if [ -v "$XDG_SESSION_TYPE" ]; then
-                return
-              fi
-              case $XDG_VTNR in
-                (1)
-                  export XDG_SESSION_TYPE=wayland
-                  ;;
-                (*)
-                  export XDG_SESSION_TYPE=tty
-                  ;;
-              esac
-            }
-            sessionCommands+=('setXdgSessionType')
+            # this is *probably not necessary*.
+            # historically, Komikku needed to know if it was running under X or Wayland, and used XDG_SESSION_TYPE for that.
+            # but unless this is a super common idiom, managing it here is just ugly.
+            # setXdgSessionType() {
+            #   case $(tty) in
+            #     (/dev/pts*)
+            #       export XDG_SESSION_TYPE=tty
+            #       ;;
+            #   esac
+            # }
+            # sessionCommands+=('setXdgSessionType')
             sourceEnv() {
               # source env vars and the like, as systemd would. `man environment.d`
               for env in ~/.config/environment.d/*.conf; do