Make screen_size handling in tui cleaner

Now screen size is fetched only for output_fd rather than sys.stdout

kittens/diff/render.py

@@ -9,7 +9,7 @@ from math import ceil
 
 from kitty.fast_data_types import truncate_point_for_length, wcswidth
 
-from ..tui.images import can_display_images, screen_size
+from ..tui.images import can_display_images
 from .collect import (
     Segment, data_for_path, highlights_for_path, is_image, lines_for_path,
     path_name_map, sanitize
@@ -371,12 +371,11 @@ def rename_lines(path, other_path, args, columns, margin_size):
 
 class Image:
 
-    def __init__(self, image_id, width, height, margin_size):
+    def __init__(self, image_id, width, height, margin_size, screen_size):
         self.image_id = image_id
         self.width, self.height = width, height
-        ss = screen_size()
-        self.rows = int(ceil(self.height / ss.cell_height))
-        self.columns = int(ceil(self.width / ss.cell_width))
+        self.rows = int(ceil(self.height / screen_size.cell_height))
+        self.columns = int(ceil(self.width / screen_size.cell_width))
         self.margin_size = margin_size
 
 
@@ -400,7 +399,7 @@ def render_image(path, is_left, available_cols, margin_size, image_manager):
         lnum += 1
 
     try:
-        image_id, width, height = image_manager.send_image(path, available_cols - margin_size, screen_size().rows - 2)
+        image_id, width, height = image_manager.send_image(path, available_cols - margin_size, image_manager.screen_size.rows - 2)
     except Exception as e:
         yield from yield_split(_('Failed to render image, with error:'))
         yield from yield_split(' '.join(str(e).splitlines()))
@@ -409,7 +408,7 @@ def render_image(path, is_left, available_cols, margin_size, image_manager):
             width, height, human_readable(len(data_for_path(path))))
     yield from yield_split(meta)
     bg_line = m + fmt(' ' * available_cols)
-    img = Image(image_id, width, height, margin_size)
+    img = Image(image_id, width, height, margin_size, image_manager.screen_size)
     for r in range(img.rows):
         yield bg_line, Reference(path, LineRef(lnum)), ImagePlacement(img, r)
         lnum += 1

kittens/tui/images.py

@@ -9,7 +9,7 @@ from base64 import standard_b64encode
 from collections import defaultdict, deque
 from itertools import count
 
-from kitty.utils import fit_image, screen_size_function
+from kitty.utils import fit_image
 
 from .operations import cursor
 
@@ -18,7 +18,6 @@ try:
     codecs.lookup(fsenc)
 except Exception:
     fsenc = 'utf-8'
-screen_size = screen_size_function()
 
 
 class ImageData:
@@ -123,6 +122,10 @@ class ImageManager:
     def next_image_id(self):
         return next(self.image_id_counter) + 2
 
+    @property
+    def screen_size(self):
+        return self.handler.screen_size
+
     def __enter__(self):
         import tempfile
         self.tdir = tempfile.mkdtemp(prefix='kitten-images-')
@@ -190,7 +193,7 @@ class ImageManager:
                 self.failed_images[path] = e
                 raise
         m = self.image_data[path]
-        ss = screen_size()
+        ss = self.screen_size
         if max_cols is None:
             max_cols = ss.cols
         if max_rows is None:

kittens/tui/loop.py

@@ -27,8 +27,6 @@ from kitty.utils import screen_size_function
 from .handler import Handler
 from .operations import init_state, reset_state
 
-screen_size = screen_size_function()
-
 
 def debug(*a, **kw):
     from base64 import standard_b64encode
@@ -156,6 +154,7 @@ class Loop:
                  sanitize_bracketed_paste='[\x03\x04\x0e\x0f\r\x07\x7f\x8d\x8e\x8f\x90\x9b\x9d\x9e\x9f]'):
         self.input_fd = sys.stdin.fileno() if input_fd is None else input_fd
         self.output_fd = sys.stdout.fileno() if output_fd is None else output_fd
+        self._get_screen_size = screen_size_function(self.output_fd)
         self.wakeup_read_fd, self.wakeup_write_fd = safe_pipe()
         # For some reason on macOS the DefaultSelector fails when input_fd is
         # open('/dev/tty')
@@ -320,8 +319,8 @@ class Loop:
     def _wakeup_ready(self, handler):
         data = os.read(self.wakeup_read_fd, 1024)
         if b'r' in data:
-            screen_size.changed = True
-            handler.on_resize(screen_size())
+            self._get_screen_size.changed = True
+            handler.on_resize(self._get_screen_size())
         if b't' in data:
             handler.on_term()
         if b'i' in data:
@@ -386,7 +385,7 @@ class Loop:
                 image_manager = handler.image_manager_class(handler)
             keep_going = True
             try:
-                handler._initialize(screen_size(), self.quit, self.wakeup, self.start_job, debug, image_manager)
+                handler._initialize(self._get_screen_size(), self.quit, self.wakeup, self.start_job, debug, image_manager)
                 with handler:
                     while keep_going:
                         has_data_to_write = bool(handler.write_buf)
@@ -415,7 +414,7 @@ class Loop:
         handler = UnhandledException(tb)
         handler.write_buf = []
         handler._term_manager = term_manager
-        handler._initialize(screen_size(), self.quit, self.wakeup, self.start_job, debug)
+        handler._initialize(self._get_screen_size(), self.quit, self.wakeup, self.start_job, debug)
         with handler:
             while True:
                 has_data_to_write = bool(handler.write_buf)