Line wrap interpreter content

When lines exceed our terminal width we cropped the content. Clearly this sucks since it makes that content impossible to... well, get. Wrapping lines that exceed our panel width with a two space indentation. https://trac.torproject.org/projects/tor/ticket/28297

Line wrap interpreter content
75052e8d · Damian Johnson · 6492a3a1 · 75052e8d · 75052e8d
Commit 75052e8d authored Jan 4, 2019 by Damian Johnson
--- a/nyx/panel/interpreter.py
+++ b/nyx/panel/interpreter.py
@@ -7,6 +7,7 @@ information, tab completion, and other usability features.
 """

 import curses
+import threading
 import nyx.curses
 import nyx.panel

@@ -53,6 +54,12 @@ class InterpreterPanel(nyx.panel.Panel):
    self._lines = []
    self._user_inputs = []  # previous user inputs

+    # cache for the line wrapped content we display
+
+    self._wrapped_lines = []
+    self._wrapped_line_lock = threading.RLock()
+    self._wrapped_line_width = 80
+
    controller = tor_controller()
    self._autocompleter = stem.interpreter.autocomplete.Autocompleter(controller)
    self._interpreter = stem.interpreter.commands.ControlInterpreter(controller)
@@ -60,7 +67,7 @@ class InterpreterPanel(nyx.panel.Panel):
  def key_handlers(self):
    def _scroll(key):
      page_height = self.get_height() - 1
-      is_changed = self._scroller.handle_key(key, len(self._lines) + 1, page_height)
+      is_changed = self._scroller.handle_key(key, len(self._get_lines()) + 1, page_height)

      if is_changed:
        self.redraw()
@@ -71,7 +78,7 @@ class InterpreterPanel(nyx.panel.Panel):

      return nyx.curses.str_input(
        4 + self._x_offset,
-        self.get_top() + max(1, min(len(self._lines) + 1, self.get_height() - 1)),
+        self.get_top() + max(1, min(len(self._get_lines()) + 1, self.get_height() - 1)),
        backlog = self._user_inputs,
        tab_completion = self._autocompleter.matches
      )
@@ -98,11 +105,11 @@ class InterpreterPanel(nyx.panel.Panel):
          self._is_input_mode = False
          break

-        self._lines.append(_format_prompt_input(user_input, prompt))
+        self._add_line(_format_prompt_input(user_input, prompt))

        if response:
          for line in response.split('\n'):
-            self._lines.append([(text, attr) for text, attr in nyx.curses.asci_to_curses(line)])
+            self._add_line([(text, attr) for text, attr in nyx.curses.asci_to_curses(line)])

      self.redraw()

@@ -111,13 +118,49 @@ class InterpreterPanel(nyx.panel.Panel):
      nyx.panel.KeyHandler('arrows', 'scroll up and down', _scroll, key_func = lambda key: key.is_scroll()),
    )

+  def _add_line(self, line):
+    with self._wrapped_line_lock:
+      self._lines.append(line)
+
+      wrapped_line = []
+
+      for text, attr in line:
+        while text:
+          wrapped_line.append((text[:self._wrapped_line_width], attr))
+          text = text[self._wrapped_line_width:]
+
+          if text:
+            text = '  ' + text  # indent wrapped lines
+            self._wrapped_lines.append(wrapped_line)
+            wrapped_line = []
+
+      self._wrapped_lines.append(wrapped_line)
+
+  def _get_lines(self, width = None):
+    with self._wrapped_line_lock:
+      if width and width != self._wrapped_line_width:
+        # Our panel size has changed. As such, line wrapping needs to be re-cached.
+
+        lines = self._lines
+
+        self._lines = []
+        self._wrapped_lines = []
+        self._wrapped_line_width = width
+
+        for line in lines:
+          self._add_line(line)
+
+      return self._wrapped_lines
+
  def _draw(self, subwindow):
    if self._is_input_mode:
      subwindow.addstr(0, 0, 'Control Interpreter (enter "/help" for usage or a blank line to stop):', HIGHLIGHT)
    else:
      subwindow.addstr(0, 0, 'Control Interpreter:', HIGHLIGHT)

-    scroll = self._scroller.location(len(self._lines) + 1, subwindow.height - 1)
+    lines = self._get_lines(subwindow.width - self._x_offset)
+
+    scroll = self._scroller.location(len(lines) + 1, subwindow.height - 1)

    if self._interpreter.is_multiline_context:
      prompt = [MULTILINE_PROMPT]
@@ -126,11 +169,11 @@ class InterpreterPanel(nyx.panel.Panel):
    else:
      prompt = [PROMPT, PROMPT_USAGE]

-    if len(self._lines) > subwindow.height - 2:
+    if len(lines) > subwindow.height - 2:
      self._x_offset = 2
-      subwindow.scrollbar(1, scroll, len(self._lines) + 1)
+      subwindow.scrollbar(1, scroll, len(lines) + 1)

-    visible_lines = self._lines[scroll:scroll + subwindow.height - 1]
+    visible_lines = lines[scroll:scroll + subwindow.height - 1]

    if len(visible_lines) < subwindow.height - 1:
      visible_lines.append(prompt)

--- a/web/changelog/index.html
+++ b/web/changelog/index.html
@@ -96,6 +96,7 @@
          <ul>
            <li>Geoip information unavailable for inbound connections</li>
            <li>Dialog showing exit statistics crashed when no data was available (<a href="https://trac.torproject.org/projects/tor/ticket/25801">ticket</a>)</li>
+            <li>More strictly scrub sensitive connection information (<a href="https://trac.torproject.org/projects/tor/ticket/27475">ticket</a>)</li>
          </ul>
        </li>

@@ -114,6 +115,7 @@

        <li><span class="component">Interpreter</span>
          <ul>
+            <li>Line wrap content (<b><a href="https://trac.torproject.org/projects/tor/ticket/28297">ticket</a></b>)</li>
            <li>Large amounts of content made panel sluggish (<b><a href="https://trac.torproject.org/projects/tor/ticket/28902">ticket</a></b>)</li>
          </ul>
        </li>