Fixed prompt sometimes not clearing.

rtv/terminal.py

@@ -411,12 +411,19 @@ class Terminal(object):
 
         n_rows, n_cols = self.stdscr.getmaxyx()
         attr = curses.A_BOLD | Color.CYAN
-        prompt = self.clean(prompt, n_cols - 1)
-        window = self.stdscr.derwin(
-            1, n_cols - len(prompt), n_rows - 1, len(prompt))
-        window.attrset(attr)
-        self.add_line(self.stdscr, prompt, n_rows-1, 0, attr)
-        self.stdscr.refresh()
+        prompt = self.clean(prompt, n_cols-1)
+
+        # Create a new window to draw the text at the bottom of the screen,
+        # so we can erase it when we're done.
+        prompt_win = curses.newwin(1, len(prompt)+1, n_rows-1, 0)
+        self.add_line(prompt_win, prompt, attr=attr)
+        prompt_win.refresh()
+
+        # Create a separate window for text input
+        input_win = curses.newwin(1, n_cols-len(prompt), n_rows-1, len(prompt))
+        input_win.attrset(attr)
+        input_win.refresh()
+
         if key:
             curses.curs_set(1)
             ch = self.getch()
@@ -426,7 +433,15 @@ class Terminal(object):
             text = ch if ch != self.ESCAPE else None
             curses.curs_set(0)
         else:
-            text = self.text_input(window)
+            text = self.text_input(input_win)
+
+        prompt_win.clear()
+        input_win.clear()
+        del prompt_win
+        del input_win
+        self.stdscr.touchwin()
+        self.stdscr.refresh()
+
         return text
 
     def prompt_y_or_n(self, prompt):

tests/test_terminal.py

@@ -218,7 +218,7 @@ def test_prompt_input(terminal, stdscr, ascii):
     assert isinstance(terminal.prompt_input('hi'), six.text_type)
 
     attr = Color.CYAN | curses.A_BOLD
-    stdscr.addstr.assert_called_with(39, 0, 'hi'.encode('ascii'), attr)
+    stdscr.subwin.addstr.assert_called_with(0, 0, 'hi'.encode('ascii'), attr)
     assert window.nlines == 1
     assert window.ncols == 78
 
@@ -236,25 +236,26 @@ def test_prompt_y_or_n(terminal, stdscr):
 
     stdscr.getch.side_effect = [ord('y'), ord('N'), terminal.ESCAPE, ord('a')]
     attr = Color.CYAN | curses.A_BOLD
+    text = 'hi'.encode('ascii')
 
     # Press 'y'
     assert terminal.prompt_y_or_n('hi')
-    stdscr.addstr.assert_called_with(39, 0, 'hi'.encode('ascii'), attr)
+    stdscr.subwin.addstr.assert_called_with(0, 0, text, attr)
     assert not curses.flash.called
 
     # Press 'N'
     assert not terminal.prompt_y_or_n('hi')
-    stdscr.addstr.assert_called_with(39, 0, 'hi'.encode('ascii'), attr)
+    stdscr.subwin.addstr.assert_called_with(0, 0, text, attr)
     assert not curses.flash.called
 
     # Press Esc
     assert not terminal.prompt_y_or_n('hi')
-    stdscr.addstr.assert_called_with(39, 0, 'hi'.encode('ascii'), attr)
+    stdscr.subwin.addstr.assert_called_with(0, 0, text, attr)
     assert not curses.flash.called
 
     # Press an invalid key
     assert not terminal.prompt_y_or_n('hi')
-    stdscr.addstr.assert_called_with(39, 0, 'hi'.encode('ascii'), attr)
+    stdscr.subwin.addstr.assert_called_with(0, 0, text, attr)
     assert curses.flash.called