tfdbg: Curses CLI: Fill line-end whitespace with default color pair

to prevent spurious color pairs from appearing in certain text
terminal environments.

RELNOTES: Bug fix: tfdbg curses CLI: fix spurious background colors in some text terminals.
PiperOrigin-RevId: 189742433

1 files changed, 19 insertions, 0 deletions

diff --git a/tensorflow/python/debug/cli/curses_ui.py b/tensorflow/python/debug/cli/curses_ui.py
index bb52f90512..f66cefb427 100644
--- a/tensorflow/python/debug/cli/curses_ui.py
+++ b/tensorflow/python/debug/cli/curses_ui.py
@@ -1185,6 +1185,22 @@ class CursesUI(base_ui.BaseUI):
       self._main_menu = None
       self._main_menu_pad = None
 
+  def _pad_line_end_with_whitespace(self, pad, row, line_end_x):
+    """Pad the whitespace at the end of a line with the default color pair.
+
+    Prevents spurious color pairs from appearing at the end of the lines in
+    certain text terimnals.
+
+    Args:
+      pad: The curses pad object to operate on.
+      row: (`int`) row index.
+      line_end_x: (`int`) column index of the end of the line (beginning of
+        the whitespace).
+    """
+    if line_end_x < self._max_x - 2:
+      pad.addstr(row, line_end_x, " " * (self._max_x - 3 - line_end_x),
+                 self._default_color_pair)
+
   def _screen_add_line_to_output_pad(self, pad, row, txt, color_segments=None):
     """Render a line in a text pad.
 
@@ -1208,6 +1224,7 @@ class CursesUI(base_ui.BaseUI):
 
     if not color_segments:
       pad.addstr(row, 0, txt, self._default_color_pair)
+      self._pad_line_end_with_whitespace(pad, row, len(txt))
       return
 
     if not isinstance(color_segments, list):
@@ -1248,6 +1265,8 @@ class CursesUI(base_ui.BaseUI):
     for segment, color_pair in zip(all_segments, all_color_pairs):
       if segment[1] < self._max_x:
         pad.addstr(row, segment[0], txt[segment[0]:segment[1]], color_pair)
+    if all_segments:
+      self._pad_line_end_with_whitespace(pad, row, all_segments[-1][1])
 
   def _screen_scroll_output_pad(self, pad, viewport_top, viewport_left,
                                 screen_location_top, screen_location_left,