Use get_wch() if available, otherwise use the old (maybe buggy) method.

This makes it possible to read the ctrl+arrows keys with python3.3, assign
ctrl+left/right to next/previous tab, in the default config.

1 files changed, 87 insertions, 18 deletions

diff --git a/src/keyboard.py b/src/keyboard.py
index c8f4b60c..71bdd0d1 100644
--- a/src/keyboard.py
+++ b/src/keyboard.py
@@ -12,6 +12,11 @@ of the time ONE char, but may be longer if it's a keyboard
 shortcut, like ^A, M-a or KEY_RESIZE)
 """
 
+import curses
+import curses.ascii
+import logging
+log = logging.getLogger(__name__)
+
 def get_next_byte(s):
     """
     Read the next byte of the utf-8 char
@@ -27,12 +32,15 @@ def get_next_byte(s):
         return (None, c)
     return (ord(c), c.encode('latin-1')) # returns a number and a bytes object
 
-def read_char(s, timeout=1000):
+def get_char_list_old(s):
     """
-    Read one utf-8 char
+    Kept for compatibility for python versions without get_wchar()
+    (introduced in 3.3) Read one or more bytes, concatenate them to create a
+    unicode char. Also treat special bytes to create special chars (like
+    control, alt, etc), returns one or more utf-8 chars
+
     see http://en.wikipedia.org/wiki/UTF-8#Description
     """
-    s.timeout(timeout) # The timeout for timed events to be checked every second
     ret_list = []
     # The list of all chars. For example if you paste a text, the list the chars pasted
     # so that they can be handled at once.
@@ -41,7 +49,7 @@ def read_char(s, timeout=1000):
         if not isinstance(first, int): # Keyboard special, like KEY_HOME etc
             return [char]
         if first == 127 or first == 8:
-            return ["KEY_BACKSPACE"]
+            ret_list.append("KEY_BACKSPACE")
         s.timeout(0)            # we are now getting the missing utf-8 bytes to get a whole char
         if first < 127:  # ASCII char on one byte
             if first <= 26:         # transform Ctrl+* keys
@@ -50,7 +58,7 @@ def read_char(s, timeout=1000):
                 (first, char) = get_next_byte(s)
                 continue
             if first == 27:
-                second = read_char(s, 0)
+                second = get_char_list_old(s)
                 if second is None: # if escape was pressed, a second char
                                    # has to be read. But it timed out.
                     return None
@@ -73,22 +81,83 @@ def read_char(s, timeout=1000):
             return None
         # s.timeout(1)            # timeout to detect a paste of many chars
         (first, char) = get_next_byte(s)
-    if not ret_list:
-        # nothing at all was read, that’s a timed event timeout
-        return None
-    if len(ret_list) != 1:
-        if ret_list[-1] == '^M':
-            ret_list.pop(-1)
-        return [char if char != '^M' else '^J' for char in ret_list]
     return ret_list
 
+def get_char_list_new(s):
+    ret_list = []
+    while True:
+        try:
+            key = s.get_wch()
+        except curses.error:
+            # No input, this means a timeout occurs.
+            return ret_list
+        s.timeout(0)
+        if isinstance(key, int):
+            ret_list.append(curses.keyname(key).decode())
+        else:
+            if curses.ascii.isctrl(key):
+                key = curses.unctrl(key).decode()
+                # Here special cases for alt keys, where we get a ^[ and then a second char
+                if key == '^[':
+                    try:
+                        part = s.get_wch()
+                    except curses.error:
+                        pass
+                    else:
+                        key = 'M-%s' % part
+                    # and an even more special case for keys like
+                    # ctrl+arrows, where we get ^[, then [, then a third
+                    # char.
+                    if key == 'M-[':
+                        try:
+                            part = s.get_wch()
+                        except curses.error:
+                            pass
+                        else:
+                            key = '%s-%s' % (key, part)
+            ret_list.append('^M' if key == '\r' else key)
+
+class Keyboard(object):
+    def __init__(self):
+        self.get_char_list = get_char_list_new
+
+    def get_user_input(self, s, timeout=1000):
+        """
+        Returns a list of all the available characters to read (for example it
+        may contain a whole text if there’s some lag, or the user pasted text,
+        or the user types really really fast).  Also it can return None, meaning
+        that it’s time to do some other checks (because this function is
+        blocking, we need to get out of it every now and then even if nothing
+        was entered).
+        """
+        s.timeout(timeout) # The timeout for timed events to be checked every second
+        try:
+            ret_list = self.get_char_list(s)
+        except AttributeError:
+            # caught if screen.get_wch() does not exist. In that case we use the
+            # old version, so this exception is caught only once. No efficiency
+            # issue here.
+            log.debug("get_wch() missing, switching to old keyboard method")
+            self.get_char_list = get_char_list_old
+            ret_list = self.get_char_list(s)
+        if not ret_list:
+            # nothing at all was read, that’s a timed event timeout
+            return None
+        if len(ret_list) != 1:
+            if ret_list[-1] == '^M':
+                ret_list.pop(-1)
+            return [char if char != '^M' else '^J' for char in ret_list]
+        return ret_list
+
+keyboard = Keyboard()
+
 if __name__ == '__main__':
-    import curses
     s = curses.initscr()
-    curses.curs_set(1)
-    curses.noecho()
-    curses.nonl()
-    s.keypad(True)
     curses.noecho()
+    curses.cbreak()
+    s.keypad(1)
+
     while True:
-        s.addstr('%s\n' % read_char(s))
+        chars = keyboard.get_user_input(s)
+        for char in chars if chars else '':
+            s.addstr('%s ' % (char))