screen-locker: add lockCmdEnv option (#6592)

modules/services/screen-locker.nix

@@ -31,6 +31,14 @@ in {
       example = "\${pkgs.i3lock}/bin/i3lock -n -c 000000";
     };
 
+    lockCmdEnv = lib.mkOption {
+      type = types.listOf types.str;
+      default = [ ];
+      example = [ "XSECURELOCK_PAM_SERVICE=xsecurelock" ];
+      description =
+        "Environment variables to source a with the locker command (lockCmd).";
+    };
+
     inactiveInterval = mkOption {
       type = types.int;
       default = 10;
@@ -127,6 +135,7 @@ in {
           ExecStart = concatStringsSep " "
             ([ "${cfg.xss-lock.package}/bin/xss-lock" "-s \${XDG_SESSION_ID}" ]
               ++ cfg.xss-lock.extraOptions ++ [ "-- ${cfg.lockCmd}" ]);
+          Environment = cfg.lockCmdEnv;
           Restart = "always";
         };
       };

tests/modules/services/screen-locker/basic-configuration.nix

@@ -5,6 +5,7 @@
     enable = true;
     inactiveInterval = 5;
     lockCmd = "${pkgs.i3lock}/bin/i3lock -n -c AA0000";
+    lockCmdEnv = [ "DISPLAY=:0" "XAUTHORITY=/custom/path/.Xauthority" ];
     xss-lock = { extraOptions = [ "-test" ]; };
     xautolock = {
       enable = true;
@@ -19,6 +20,8 @@
 
     assertFileExists $xssService
     assertFileRegex $xssService 'ExecStart=.*/bin/xss-lock.*-test.*i3lock -n -c AA0000'
+    assertFileRegex $xssService 'Environment=DISPLAY=:0'
+    assertFileRegex $xssService 'Environment=XAUTHORITY=/custom/path/.Xauthority'
     assertFileRegex $xssService 'Restart=always'
     assertFileExists $xautolockService
     assertFileRegex $xautolockService 'ExecStart=.*/bin/xautolock.*-time 5.*-detectsleep.*-test.*'

tests/modules/services/screen-locker/moved-options.nix

@@ -5,6 +5,7 @@
     enable = true;
     inactiveInterval = 5;
     lockCmd = "${pkgs.i3lock}/bin/i3lock -n -c AA0000";
+    lockCmdEnv = [ "DISPLAY=:0" "XAUTHORITY=/custom/path/.Xauthority" ];
     xssLockExtraOptions = [ "-test" ];
     xautolockExtraOptions = [ "-test" ];
     enableDetectSleep = true;