Refactor: allow initializing tmux_cmd with pre-set results

Author: tony

src/libtmux/common.py

@@ -219,7 +219,21 @@ class tmux_cmd:
         Renamed from ``tmux`` to ``tmux_cmd``.
     """
 
-    def __init__(self, *args: t.Any) -> None:
+    def __init__(
+        self,
+        *args: t.Any,
+        cmd: list[str] | None = None,
+        stdout: list[str] | None = None,
+        stderr: list[str] | None = None,
+        returncode: int | None = None,
+    ) -> None:
+        if cmd is not None:
+            self.cmd = cmd
+            self.stdout = stdout or []
+            self.stderr = stderr or []
+            self.returncode = returncode
+            return
+
         tmux_bin = shutil.which("tmux")
         if not tmux_bin:
             raise exc.TmuxCommandNotFound
@@ -238,20 +252,20 @@ def __init__(self, *args: t.Any) -> None:
                 text=True,
                 errors="backslashreplace",
             )
-            stdout, stderr = self.process.communicate()
+            stdout_str, stderr_str = self.process.communicate()
             returncode = self.process.returncode
         except Exception:
             logger.exception(f"Exception for {subprocess.list2cmdline(cmd)}")
             raise
 
         self.returncode = returncode
 
-        stdout_split = stdout.split("\n")
+        stdout_split = stdout_str.split("\n")
         # remove trailing newlines from stdout
         while stdout_split and stdout_split[-1] == "":
             stdout_split.pop()
 
-        stderr_split = stderr.split("\n")
+        stderr_split = stderr_str.split("\n")
         self.stderr = list(filter(None, stderr_split))  # filter empty values
 
         if "has-session" in cmd and len(self.stderr) and not stdout_split: