Preserve env vars from onvoking env when creating new os window via single instance

docs/changelog.rst

@@ -128,6 +128,9 @@ Detailed list of changes
 - Fix a regression in 0.36.0 that caused using = with single letter options to
   no longer work correctly (:iss:`8556`)
 
+- Single instance: Preserve environment variables from invoking environment in
+  newly created window (:disc:`8567`)
+
 
 0.41.1 [2025-04-03]
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

kitty/boss.py

@@ -870,8 +870,10 @@ class Boss:
                 args.session = ''
             if not os.path.isabs(args.directory):
                 args.directory = os.path.join(data['cwd'], args.directory)
+            from .child import process_env
+            clean_env = process_env(data['environ'])
             focused_os_window = os_window_id = 0
-            for session in create_sessions(opts, args, respect_cwd=True):
+            for session in create_sessions(opts, args, respect_cwd=True, env_when_no_session=clean_env):
                 if not session.has_non_background_processes:
                     # background only do not create an OS Window
                     from .launch import LaunchSpec, launch

kitty/child.py

@@ -145,8 +145,8 @@ def environ_of_process(pid: int) -> dict[str, str]:
     return parse_environ_block(_environ_of_process(pid))
 
 
-def process_env() -> dict[str, str]:
-    ans = dict(os.environ)
+def process_env(env: dict[str, str] | None = None) -> dict[str, str]:
+    ans = dict(os.environ if env is None else env)
     ssl_env_var = getattr(sys, 'kitty_ssl_env_var', None)
     if ssl_env_var is not None:
         ans.pop(ssl_env_var, None)

kitty/session.py

@@ -241,6 +241,7 @@ def create_sessions(
     cwd_from: Optional['CwdRequest'] = None,
     respect_cwd: bool = False,
     default_session: str | None = None,
+    env_when_no_session: dict[str, str] | None = None,
 ) -> Iterator[Session]:
     if args and args.session:
         if args.session == "none":
@@ -276,6 +277,6 @@ def create_sessions(
         cmd = args.args if args and args.args else resolved_shell(opts)
         from kitty.tabs import SpecialWindow
         cwd: str | None = args.directory if respect_cwd and args else None
-        special_window = SpecialWindow(cmd, cwd_from=cwd_from, cwd=cwd, hold=bool(args and args.hold))
+        special_window = SpecialWindow(cmd, cwd_from=cwd_from, cwd=cwd, env=env_when_no_session, hold=bool(args and args.hold))
     ans.add_special_window(special_window)
     yield ans