Server(feat[new_session]): add detach-others, no-size, config flags

why: new-session supports flags for detaching other clients, suppressing
initial sizing, and specifying config files that were not exposed.
what:
- Add detach_others (-D), no_size (-X), config_file (-f) parameters
- Skip -A (attach-or-create) as it requires a terminal and does not work
  in libtmux's programmatic non-terminal context
- Add test for config_file parameter

Author: tony

src/libtmux/server.py

@@ -472,6 +472,9 @@ def new_session(
         y: int | DashLiteral | None = None,
         environment: dict[str, str] | None = None,
         *args: t.Any,
+        detach_others: bool | None = None,
+        no_size: bool | None = None,
+        config_file: StrPath | None = None,
         **kwargs: t.Any,
     ) -> Session:
         """Create new session, returns new :class:`Session`.
@@ -518,6 +521,18 @@ def new_session(
         y : int | str, optional
             Force the specified height instead of the tmux default for a
             detached session
+        detach_others : bool, optional
+            Detach other clients from the session (``-D`` flag).
+
+            .. versionadded:: 0.45
+        no_size : bool, optional
+            Do not set the initial window size (``-X`` flag).
+
+            .. versionadded:: 0.45
+        config_file : str or PathLike, optional
+            Specify an alternative configuration file (``-f`` flag).
+
+            .. versionadded:: 0.45
 
         Returns
         -------
@@ -585,6 +600,15 @@ def new_session(
                 f"-F{format_string}",
             )
 
+            if detach_others:
+                tmux_args += ("-D",)
+
+            if no_size:
+                tmux_args += ("-X",)
+
+            if config_file is not None:
+                tmux_args += ("-f", str(pathlib.Path(config_file).expanduser()))
+
             if session_name is not None:
                 tmux_args += (f"-s{session_name}",)
 

tests/test_server.py

@@ -458,3 +458,18 @@ def test_tmux_bin_invalid_path_raise_if_dead() -> None:
     s = Server(tmux_bin="/nonexistent/tmux")
     with pytest.raises(exc.TmuxCommandNotFound):
         s.raise_if_dead()
+
+
+def test_new_session_config_file(
+    server: Server,
+    tmp_path: pathlib.Path,
+) -> None:
+    """Test Server.new_session() with config_file flag."""
+    conf = tmp_path / "test.conf"
+    conf.write_text("set -g status off\n")
+
+    session = server.new_session(
+        session_name="conf_test",
+        config_file=str(conf),
+    )
+    assert session.session_name == "conf_test"