added lazy command fields to history

tests/test_history.py

@@ -5,8 +5,8 @@ import os
 import nose
 from nose.tools import assert_equal, assert_true
 
-from xonsh.history import History
 from xonsh.lazyjson import LazyJSON
+from xonsh.history import History, CommandField
 
 HIST_TEST_KWARGS = dict(sessionid='SESSIONID', gc=False)
 
@@ -48,6 +48,25 @@ def test_hist_flush():
     os.remove(FNAME)
 
 
+def test_cmd_field():
+    FNAME = 'xonsh-SESSIONID.json'
+    FNAME += '.cmdfield'
+    hist = History(filename=FNAME, here='yup', **HIST_TEST_KWARGS)
+    # in-memory
+    hf = hist.append({'rtn': 1})
+    yield assert_true, hf is None
+    yield assert_equal, 1, hist.rtns[0]
+    yield assert_equal, 1, hist.rtns[-1]
+    yield assert_equal, None, hist.outs[-1]
+    # slice
+    yield assert_equal, [1], hist.rtns[:]
+    # on disk
+    hf = hist.flush()
+    yield assert_true, hf is not None
+    yield assert_equal, 1, hist.rtns[0]
+    yield assert_equal, 1, hist.rtns[-1]
+    yield assert_equal, None, hist.outs[-1]
+    os.remove(FNAME)
 
 if __name__ == '__main__':
     nose.runmodule()

xonsh/history.py

@@ -98,6 +98,7 @@ class HistoryFlusher(Thread):
             self.queue.popleft()
 
     def i_am_at_the_front(self):
+        """Tests if the flusher is at the front of the queue."""
         return self is self.queue[0]
 
     def dump(self):
@@ -146,10 +147,10 @@ class CommandField(Sequence):
         if size - bufsize <= key:  # key is in buffer
             return self.hist.buffer[key + bufsize - size].get(self.field, self.default)
         # now we know we have to go into the file
-        queue = self.hist.queue
+        queue = self.hist._queue
         queue.append(self)
-        with self.hist.cond as cond:
-            cond.wait_for(self.i_am_at_the_front)
+        with self.hist._cond:
+            self.hist._cond.wait_for(self.i_am_at_the_front)
             with open(self.hist.filename, 'r', newline='\n') as f:
                 lj = lazyjson.LazyJSON(f, reopen=False)
                 rtn = lj['cmds'][key].get(self.field, self.default)
@@ -159,7 +160,8 @@ class CommandField(Sequence):
         return rtn
 
     def i_am_at_the_front(self):
-        return self is self.hist.queue[0]
+        """Tests if the command field is at the front of the queue."""
+        return self is self.hist._queue[0]
 
 
 class History(object):