forked from RustPython/RustPython
-
Notifications
You must be signed in to change notification settings - Fork 0
Expand file tree
/
Copy pathsliceable.rs
More file actions
306 lines (272 loc) · 9.07 KB
/
sliceable.rs
File metadata and controls
306 lines (272 loc) · 9.07 KB
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
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
use std::ops::Range;
// export through slicable module, not slice.
pub use crate::builtins::slice::{saturate_index, SaturatedSlice};
use crate::{
builtins::{
int::PyInt,
slice::{PySlice, SaturatedSliceIter},
},
PyObject, PyResult, TryFromBorrowedObject, TypeProtocol, VirtualMachine,
};
pub trait SliceableSequenceMutOp {
type Item: Clone;
fn as_slice(&self) -> &[Self::Item];
fn do_set(&mut self, index: usize, value: Self::Item);
fn do_delele(&mut self, index: usize);
/// as CPython, length of range and items could be different, function must act like Vec::splice()
fn do_set_range(&mut self, range: Range<usize>, items: &[Self::Item]);
fn do_delete_range(&mut self, range: Range<usize>);
fn do_set_indexes<I>(&mut self, indexes: I, items: &[Self::Item])
where
I: Iterator<Item = usize>;
/// indexes must be positive order
fn do_delete_indexes<I>(&mut self, range: Range<usize>, indexes: I)
where
I: Iterator<Item = usize>;
fn set_item_by_index(
&mut self,
vm: &VirtualMachine,
index: isize,
value: Self::Item,
) -> PyResult<()> {
let pos = self
.as_slice()
.wrap_index(index)
.ok_or_else(|| vm.new_index_error("assigment index out of range".to_owned()))?;
self.do_set(pos, value);
Ok(())
}
fn set_item_by_slice_no_resize(
&mut self,
vm: &VirtualMachine,
slice: SaturatedSlice,
items: &[Self::Item],
) -> PyResult<()> {
let (range, step, slicelen) = slice.adjust_indices(self.as_slice().len());
if slicelen != items.len() {
Err(vm
.new_buffer_error("Existing exports of data: object cannot be re-sized".to_owned()))
} else if step == 1 {
self.do_set_range(range, items);
Ok(())
} else {
self.do_set_indexes(
SaturatedSliceIter::from_adjust_indices(range, step, slicelen),
items,
);
Ok(())
}
}
fn set_item_by_slice(
&mut self,
vm: &VirtualMachine,
slice: SaturatedSlice,
items: &[Self::Item],
) -> PyResult<()> {
let (range, step, slicelen) = slice.adjust_indices(self.as_slice().len());
if step == 1 {
self.do_set_range(range, items);
Ok(())
} else if slicelen == items.len() {
self.do_set_indexes(
SaturatedSliceIter::from_adjust_indices(range, step, slicelen),
items,
);
Ok(())
} else {
Err(vm.new_value_error(format!(
"attempt to assign sequence of size {} to extended slice of size {}",
items.len(),
slicelen
)))
}
}
fn del_item_by_index(&mut self, vm: &VirtualMachine, index: isize) -> PyResult<()> {
let pos = self
.as_slice()
.wrap_index(index)
.ok_or_else(|| vm.new_index_error("assigment index out of range".to_owned()))?;
self.do_delele(pos);
Ok(())
}
fn del_item_by_slice(&mut self, _vm: &VirtualMachine, slice: SaturatedSlice) -> PyResult<()> {
let (range, step, slicelen) = slice.adjust_indices(self.as_slice().len());
if slicelen == 0 {
Ok(())
} else if step == 1 {
self.do_set_range(range, &[]);
Ok(())
} else {
self.do_delete_indexes(
range.clone(),
SaturatedSliceIter::from_adjust_indices(range, step, slicelen).positive_order(),
);
Ok(())
}
}
}
impl<T: Clone> SliceableSequenceMutOp for Vec<T> {
type Item = T;
fn as_slice(&self) -> &[Self::Item] {
self.as_slice()
}
fn do_set(&mut self, index: usize, value: Self::Item) {
self[index] = value;
}
fn do_delele(&mut self, index: usize) {
self.remove(index);
}
fn do_set_range(&mut self, range: Range<usize>, items: &[Self::Item]) {
self.splice(range, items.to_vec());
}
fn do_delete_range(&mut self, range: Range<usize>) {
self.drain(range);
}
fn do_set_indexes<I>(&mut self, indexes: I, items: &[Self::Item])
where
I: Iterator<Item = usize>,
{
for (i, item) in indexes.zip(items) {
self.do_set(i, item.clone());
}
}
fn do_delete_indexes<I>(&mut self, range: Range<usize>, indexes: I)
where
I: Iterator<Item = usize>,
{
let mut indexes = indexes.peekable();
let mut deleted = 0;
// passing whole range, swap or overlap
for i in range.clone() {
if indexes.peek() == Some(&i) {
indexes.next();
deleted += 1;
} else {
self.swap(i - deleted, i);
}
}
// then drain (the values to delete should now be contiguous at the end of the range)
self.drain((range.end - deleted)..range.end);
}
}
#[allow(clippy::len_without_is_empty)]
pub trait SliceableSequenceOp {
type Item;
type Sliced;
fn do_get(&self, index: usize) -> Self::Item;
fn do_slice(&self, range: Range<usize>) -> Self::Sliced;
fn do_slice_reverse(&self, range: Range<usize>) -> Self::Sliced;
fn do_stepped_slice(&self, range: Range<usize>, step: usize) -> Self::Sliced;
fn do_stepped_slice_reverse(&self, range: Range<usize>, step: usize) -> Self::Sliced;
fn empty() -> Self::Sliced;
fn len(&self) -> usize;
fn wrap_index(&self, p: isize) -> Option<usize> {
wrap_index(p, self.len())
}
fn saturate_index(&self, p: isize) -> usize {
saturate_index(p, self.len())
}
fn get_item_by_slice(
&self,
_vm: &VirtualMachine,
slice: SaturatedSlice,
) -> PyResult<Self::Sliced> {
let (range, step, slicelen) = slice.adjust_indices(self.len());
let sliced = if slicelen == 0 {
Self::empty()
} else if step == 1 {
if step.is_negative() {
self.do_slice_reverse(range)
} else {
self.do_slice(range)
}
} else if step.is_negative() {
self.do_stepped_slice_reverse(range, step.unsigned_abs())
} else {
self.do_stepped_slice(range, step.unsigned_abs())
};
Ok(sliced)
}
fn get_item_by_index(&self, vm: &VirtualMachine, index: isize) -> PyResult<Self::Item> {
let pos = self
.wrap_index(index)
.ok_or_else(|| vm.new_index_error("index out of range".to_owned()))?;
Ok(self.do_get(pos))
}
}
impl<T: Clone> SliceableSequenceOp for [T] {
type Item = T;
type Sliced = Vec<T>;
#[inline]
fn do_get(&self, index: usize) -> Self::Item {
self[index].clone()
}
#[inline]
fn do_slice(&self, range: Range<usize>) -> Self::Sliced {
self[range].to_vec()
}
#[inline]
fn do_slice_reverse(&self, range: Range<usize>) -> Self::Sliced {
let mut slice = self[range].to_vec();
slice.reverse();
slice
}
#[inline]
fn do_stepped_slice(&self, range: Range<usize>, step: usize) -> Self::Sliced {
self[range].iter().step_by(step).cloned().collect()
}
#[inline]
fn do_stepped_slice_reverse(&self, range: Range<usize>, step: usize) -> Self::Sliced {
self[range].iter().rev().step_by(step).cloned().collect()
}
#[inline(always)]
fn empty() -> Self::Sliced {
Vec::new()
}
#[inline(always)]
fn len(&self) -> usize {
self.len()
}
}
pub enum SequenceIndex {
Int(isize),
Slice(SaturatedSlice),
}
impl TryFromBorrowedObject for SequenceIndex {
fn try_from_borrowed_object(vm: &VirtualMachine, obj: &PyObject) -> PyResult<Self> {
if let Some(i) = obj.payload::<PyInt>() {
// TODO: number protocol
i.try_to_primitive(vm)
.map_err(|_| {
vm.new_index_error("cannot fit 'int' into an index-sized integer".to_owned())
})
.map(Self::Int)
} else if let Some(slice) = obj.payload::<PySlice>() {
slice.to_saturated(vm).map(Self::Slice)
} else if let Some(i) = vm.to_index_opt(obj.to_owned()) {
// TODO: __index__ for indice is no more supported?
i?.try_to_primitive(vm)
.map_err(|_| {
vm.new_index_error("cannot fit 'int' into an index-sized integer".to_owned())
})
.map(Self::Int)
} else {
Err(vm.new_type_error(format!(
"indices must be integers or slices or classes that override __index__ operator, not '{}'",
obj.class()
)))
}
}
}
// Use PySliceableSequence::wrap_index for implementors
pub(crate) fn wrap_index(p: isize, len: usize) -> Option<usize> {
let neg = p.is_negative();
let p = p.wrapping_abs() as usize;
if neg {
len.checked_sub(p)
} else if p >= len {
None
} else {
Some(p)
}
}