pass size as a parameter

Author: willmcgugan

src/textual/_doc.py

@@ -30,7 +30,7 @@ def format_svg(source, language, css_class, options, md, attrs, **kwargs) -> str
             rows = int(attrs.get("lines", 24))
             columns = int(attrs.get("columns", 80))
             svg = take_svg_screenshot(
-                None, path, press, title, terminal_size=(rows, columns)
+                None, path, press, title, terminal_size=(columns, rows)
             )
         finally:
             os.chdir(cwd)
@@ -49,7 +49,7 @@ def take_svg_screenshot(
     app_path: str | None = None,
     press: Iterable[str] = ("_",),
     title: str | None = None,
-    terminal_size: tuple[int, int] = (24, 80),
+    terminal_size: tuple[int, int] = (80, 24),
 ) -> str:
     """
 
@@ -65,10 +65,6 @@ def take_svg_screenshot(
             the screenshot was taken.
 
     """
-    rows, columns = terminal_size
-
-    os.environ["COLUMNS"] = str(columns)
-    os.environ["LINES"] = str(rows)
 
     if app is None:
         assert app_path is not None
@@ -85,7 +81,11 @@ async def auto_pilot(pilot: Pilot) -> None:
         svg = app.export_screenshot(title=title)
         app.exit(svg)
 
-    svg = app.run(headless=True, auto_pilot=auto_pilot)
+    svg = app.run(
+        headless=True,
+        auto_pilot=auto_pilot,
+        size=terminal_size,
+    )
     assert svg is not None
 
     return svg

src/textual/app.py

@@ -444,7 +444,11 @@ def size(self) -> Size:
         Returns:
             Size: Size of the terminal
         """
-        return Size(*self.console.size)
+        if self._driver is not None and self._driver._size is not None:
+            width, height = self._driver._size
+        else:
+            width, height = self.console.size
+        return Size(width, height)
 
     @property
     def log(self) -> Logger:
@@ -526,10 +530,11 @@ def export_screenshot(self, *, title: str | None = None) -> str:
                 to use app title. Defaults to None.
 
         """
-
+        assert self._driver is not None, "App must be running"
+        width, height = self.size
         console = Console(
-            width=self.console.width,
-            height=self.console.height,
+            width=width,
+            height=height,
             file=io.StringIO(),
             force_terminal=True,
             color_system="truecolor",
@@ -669,12 +674,15 @@ async def run_async(
         self,
         *,
         headless: bool = False,
+        size: tuple[int, int] | None = None,
         auto_pilot: AutopilotCallbackType | None = None,
     ) -> ReturnType | None:
         """Run the app asynchronously.
 
         Args:
             headless (bool, optional): Run in headless mode (no output). Defaults to False.
+            size (tuple[int, int] | None, optional): Force terminal size to `(WIDTH, HEIGHT)`,
+                or None to auto-detect. Defaults to None.
             auto_pilot (AutopilotCallbackType): An auto pilot coroutine.
 
         Returns:
@@ -707,6 +715,7 @@ async def run_auto_pilot(
             await app._process_messages(
                 ready_callback=None if auto_pilot is None else app_ready,
                 headless=headless,
+                terminal_size=size,
             )
         finally:
             if auto_pilot_task is not None:
@@ -719,12 +728,15 @@ def run(
         self,
         *,
         headless: bool = False,
+        size: tuple[int, int] | None = None,
         auto_pilot: AutopilotCallbackType | None = None,
     ) -> ReturnType | None:
         """Run the app.
 
         Args:
             headless (bool, optional): Run in headless mode (no output). Defaults to False.
+            size (tuple[int, int] | None, optional): Force terminal size to `(WIDTH, HEIGHT)`,
+                or None to auto-detect. Defaults to None.
             auto_pilot (AutopilotCallbackType): An auto pilot coroutine.
 
         Returns:
@@ -735,6 +747,7 @@ async def run_app() -> None:
             """Run the app."""
             await self.run_async(
                 headless=headless,
+                size=size,
                 auto_pilot=auto_pilot,
             )
 
@@ -1072,7 +1085,10 @@ def _print_error_renderables(self) -> None:
         self._exit_renderables.clear()
 
     async def _process_messages(
-        self, ready_callback: CallbackType | None = None, headless: bool = False
+        self,
+        ready_callback: CallbackType | None = None,
+        headless: bool = False,
+        terminal_size: tuple[int, int] | None = None,
     ) -> None:
         self._set_active()
 
@@ -1161,7 +1177,7 @@ async def run_process_messages():
                 "type[Driver]",
                 HeadlessDriver if headless else self.driver_class,
             )
-            driver = self._driver = driver_class(self.console, self)
+            driver = self._driver = driver_class(self.console, self, size=terminal_size)
 
             driver.start_application_mode()
             try:

src/textual/driver.py

@@ -13,11 +13,17 @@
 
 class Driver(ABC):
     def __init__(
-        self, console: "Console", target: "MessageTarget", debug: bool = False
+        self,
+        console: "Console",
+        target: "MessageTarget",
+        *,
+        debug: bool = False,
+        size: tuple[int, int] | None = None,
     ) -> None:
         self.console = console
         self._target = target
         self._debug = debug
+        self._size = size
         self._loop = asyncio.get_running_loop()
         self._mouse_down_time = _clock.get_time_no_wait()
 

src/textual/drivers/headless_driver.py

@@ -14,6 +14,8 @@ def is_headless(self) -> bool:
         return True
 
     def _get_terminal_size(self) -> tuple[int, int]:
+        if self._size is not None:
+            return self._size
         width: int | None = 80
         height: int | None = 25
         import shutil

src/textual/drivers/linux_driver.py

@@ -30,9 +30,14 @@ class LinuxDriver(Driver):
     """Powers display and input for Linux / MacOS"""
 
     def __init__(
-        self, console: "Console", target: "MessageTarget", debug: bool = False
+        self,
+        console: "Console",
+        target: "MessageTarget",
+        *,
+        debug: bool = False,
+        size: tuple[int, int] | None = None,
     ) -> None:
-        super().__init__(console, target, debug)
+        super().__init__(console, target, debug=debug, size=size)
         self.fileno = sys.stdin.fileno()
         self.attrs_before: list[Any] | None = None
         self.exit_event = Event()

src/textual/drivers/windows_driver.py

@@ -18,9 +18,14 @@ class WindowsDriver(Driver):
     """Powers display and input for Windows."""
 
     def __init__(
-        self, console: "Console", target: "MessageTarget", debug: bool = False
+        self,
+        console: "Console",
+        target: "MessageTarget",
+        *,
+        debug: bool = False,
+        size: tuple[int, int] | None = None,
     ) -> None:
-        super().__init__(console, target, debug)
+        super().__init__(console, target, debug=debug, size=size)
         self.in_fileno = sys.stdin.fileno()
         self.out_fileno = sys.stdout.fileno()
 

tests/snapshot_tests/conftest.py

@@ -41,7 +41,7 @@ def snap_compare(
     def compare(
         app_path: str,
         press: Iterable[str] = ("_",),
-        terminal_size: tuple[int, int] = (24, 80),
+        terminal_size: tuple[int, int] = (80, 24),
     ) -> bool:
         """
         Compare a current screenshot of the app running at app_path, with
@@ -52,7 +52,7 @@ def compare(
         Args:
             app_path (str): The path of the app.
             press (Iterable[str]): Key presses to run before taking screenshot. "_" is a short pause.
-            terminal_size (tuple[int, int]): A pair of integers (rows, columns), representing terminal size.
+            terminal_size (tuple[int, int]): A pair of integers (WIDTH, SIZE), representing terminal size.
 
         Returns:
             bool: True if the screenshot matches the snapshot.