1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
|
# This file is part of ranger, the console file manager.
# License: GNU GPL version 3, see the file "AUTHORS" for details.
# TODO: rewrite to use deque instead of list
class HistoryEmptyException(Exception):
pass
class History(object):
def __init__(self, maxlen=None, unique=True):
assert maxlen is not None, "maxlen cannot be None"
if isinstance(maxlen, History):
self._history = list(maxlen._history)
self._index = maxlen._index
self.maxlen = maxlen.maxlen
self.unique = maxlen.unique
else:
self._history = []
self._index = 0
self.maxlen = maxlen
self.unique = unique
def add(self, item):
# Remove everything after index
if self._index < len(self._history) - 2:
del self._history[:self._index + 1]
# Remove Duplicates
if self.unique:
try:
self._history.remove(item)
except Exception:
pass
else:
if self._history and self._history[-1] == item:
del self._history[-1]
# Remove first if list is too long
if len(self._history) > max(self.maxlen - 1, 0):
del self._history[0]
# Append the item and fast forward
self._history.append(item)
self._index = len(self._history) - 1
def modify(self, item, unique=False):
if self._history and unique:
try:
self._history.remove(item)
self._index -= 1
except Exception:
pass
try:
self._history[self._index] = item
except IndexError:
self.add(item)
def rebase(self, other_history):
"""
Replace the past of this history by that of another.
This is used when creating a new tab to seamlessly blend in the history
of the old tab into the new one.
Example: if self is [a,b,C], the current item is uppercase, and
other_history is [x,Y,z], then self.merge(other_history) will result in
[x, y, C].
"""
assert isinstance(other_history, History)
if len(self._history) == 0:
self._index = 0
future_length = 0
else:
future_length = len(self._history) - self._index - 1
self._history[:self._index] = list(
other_history._history[:other_history._index + 1])
if len(self._history) > self.maxlen:
self._history = self._history[-self.maxlen:]
self._index = len(self._history) - future_length - 1
assert self._index < len(self._history)
def __len__(self):
return len(self._history)
def current(self):
if self._history:
return self._history[self._index]
else:
raise HistoryEmptyException
def top(self):
try:
return self._history[-1]
except IndexError:
raise HistoryEmptyException()
def bottom(self):
try:
return self._history[0]
except IndexError:
raise HistoryEmptyException()
def back(self):
self._index -= 1
if self._index < 0:
self._index = 0
return self.current()
def move(self, n):
self._index += n
if self._index > len(self._history) - 1:
self._index = len(self._history) - 1
if self._index < 0:
self._index = 0
return self.current()
def search(self, string, n):
if n != 0 and string:
step = n > 0 and 1 or -1
i = self._index
steps_left = steps_left_at_start = int(abs(n))
while steps_left:
i += step
if i >= len(self._history) or i < 0:
break
if self._history[i].startswith(string):
steps_left -= 1
if steps_left != steps_left_at_start:
self._index = i
return self.current()
def __iter__(self):
return self._history.__iter__()
def forward(self):
if self._history:
self._index += 1
if self._index > len(self._history) - 1:
self._index = len(self._history) - 1
else:
self._index = 0
return self.current()
def fast_forward(self):
if self._history:
self._index = len(self._history) - 1
else:
self._index = 0
|