[Python-checkins] cpython (2.7): Issue #13051: Fixed recursion errors in large or resized curses.textpad.Textbox.

Wed Dec 28 03:23:40 EST 2016

https://hg.python.org/cpython/rev/d87771d1c1e6
changeset: 105872:d87771d1c1e6
branch: 2.7
parent: 105868:84ca252ac346
user: Serhiy Storchaka <storchaka at gmail.com>
date: Wed Dec 28 10:16:06 2016 +0200
summary:
 Issue #13051: Fixed recursion errors in large or resized curses.textpad.Textbox.
Based on patch by Tycho Andersen.
files:
 Lib/curses/textpad.py | 31 ++++++++++++++++++++--------
 Lib/test/test_curses.py | 9 ++++++++
 Misc/ACKS | 1 +
 Misc/NEWS | 3 ++
 4 files changed, 35 insertions(+), 9 deletions(-)

diff --git a/Lib/curses/textpad.py b/Lib/curses/textpad.py
--- a/Lib/curses/textpad.py
+++ b/Lib/curses/textpad.py
@@ -43,16 +43,20 @@
 def __init__(self, win, insert_mode=False):
 self.win = win
 self.insert_mode = insert_mode
- (self.maxy, self.maxx) = win.getmaxyx()
- self.maxy = self.maxy - 1
- self.maxx = self.maxx - 1
+ self._update_max_yx()
 self.stripspaces = 1
 self.lastcmd = None
 win.keypad(1)
 
+ def _update_max_yx(self):
+ maxy, maxx = self.win.getmaxyx()
+ self.maxy = maxy - 1
+ self.maxx = maxx - 1
+
 def _end_of_line(self, y):
 """Go to the location of the first blank on the given line,
 returning the index of the last non-blank character."""
+ self._update_max_yx()
 last = self.maxx
 while True:
 if curses.ascii.ascii(self.win.inch(y, last)) != curses.ascii.SP:
@@ -64,8 +68,10 @@
 return last
 
 def _insert_printable_char(self, ch):
+ self._update_max_yx()
 (y, x) = self.win.getyx()
- if y < self.maxy or x < self.maxx:
+ backyx = None
+ while y < self.maxy or x < self.maxx:
 if self.insert_mode:
 oldch = self.win.inch()
 # The try-catch ignores the error we trigger from some curses
@@ -75,14 +81,20 @@
 self.win.addch(ch)
 except curses.error:
 pass
- if self.insert_mode:
- (backy, backx) = self.win.getyx()
- if curses.ascii.isprint(oldch):
- self._insert_printable_char(oldch)
- self.win.move(backy, backx)
+ if not self.insert_mode or not curses.ascii.isprint(oldch):
+ break
+ ch = oldch
+ (y, x) = self.win.getyx()
+ # Remember where to put the cursor back since we are in insert_mode
+ if backyx is None:
+ backyx = y, x
+
+ if backyx is not None:
+ self.win.move(*backyx)
 
 def do_command(self, ch):
 "Process a single editing command."
+ self._update_max_yx()
 (y, x) = self.win.getyx()
 self.lastcmd = ch
 if curses.ascii.isprint(ch):
@@ -148,6 +160,7 @@
 def gather(self):
 "Collect and return the contents of the window."
 result = ""
+ self._update_max_yx()
 for y in range(self.maxy+1):
 self.win.move(y, 0)
 stop = self._end_of_line(y)
diff --git a/Lib/test/test_curses.py b/Lib/test/test_curses.py
--- a/Lib/test/test_curses.py
+++ b/Lib/test/test_curses.py
@@ -26,6 +26,7 @@
 curses = import_module('curses')
 import_module('curses.panel')
 import_module('curses.ascii')
+import_module('curses.textpad')
 
 def requires_curses_func(name):
 return unittest.skipUnless(hasattr(curses, name),
@@ -327,6 +328,14 @@
 b = curses.tparm(curses.tigetstr("cup"), 5, 3)
 self.assertIs(type(b), bytes)
 
+ def test_issue13051(self):
+ stdscr = self.stdscr
+ box = curses.textpad.Textbox(stdscr, insert_mode=True)
+ lines, cols = stdscr.getmaxyx()
+ stdscr.resize(lines-2, cols-2)
+ # this may cause infinite recursion, leading to a RuntimeError
+ box._insert_printable_char('a')
+
 
 class TestAscii(unittest.TestCase):
 
diff --git a/Misc/ACKS b/Misc/ACKS
--- a/Misc/ACKS
+++ b/Misc/ACKS
@@ -37,6 +37,7 @@
 Mark Anacker
 Shashwat Anand
 Anders Andersen
+Tycho Andersen
 John Anderson
 Pehr Anderson
 Erik Andersén
diff --git a/Misc/NEWS b/Misc/NEWS
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -15,6 +15,9 @@
 Library
 -------
 
+- Issue #13051: Fixed recursion errors in large or resized
+ curses.textpad.Textbox. Based on patch by Tycho Andersen.
+
 - Issue #9770: curses.ascii predicates now work correctly with negative
 integers.
 
-- 
Repository URL: https://hg.python.org/cpython
