bufkit 0.7.0

Memory-backed buffer toolkit with Chunk/ChunkMut traits for predictable, explicit, and retry-friendly access; ideal for Sans-I/O style protocol parsers, database engines, and embedded systems.
Documentation 
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
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339

#![allow(unused_imports)]

#[cfg(test)]
#[cfg(all(feature = "bytes_1", feature = "std"))]
mod bytes_buf_tests {
  use bufkit::{Chunk, ChunkExt};
  use bytes_1::Bytes;

  #[test]
  fn test_remaining() {
    let data = vec![1, 2, 3, 4, 5];
    let buf = Bytes::from(data);
    assert_eq!(buf.remaining(), 5);
    assert!(buf.has_remaining());

    let empty = Bytes::new();
    assert_eq!(empty.remaining(), 0);
    assert!(!empty.has_remaining());
  }

  #[test]
  fn test_buffer() {
    let data = vec![1, 2, 3, 4, 5];
    let buf = Bytes::from(data);
    assert_eq!(buf.buffer(), &[1, 2, 3, 4, 5]);
  }

  #[test]
  fn test_advance() {
    let data = vec![1, 2, 3, 4, 5];
    let mut buf = Bytes::from(data);

    buf.advance(2);
    assert_eq!(buf.remaining(), 3);
    assert_eq!(buf.buffer(), &[3, 4, 5]);

    buf.advance(3);
    assert_eq!(buf.remaining(), 0);
    assert!(!buf.has_remaining());
  }

  #[test]
  #[should_panic]
  fn test_advance_panic() {
    let data = vec![1, 2, 3];
    let mut buf = Bytes::from(data);
    buf.advance(5); // Should panic
  }

  #[test]
  fn test_try_advance() {
    let data = vec![1, 2, 3, 4, 5];
    let mut buf = Bytes::from(data);

    assert!(buf.try_advance(3).is_ok());
    assert_eq!(buf.remaining(), 2);

    let err = buf.try_advance(5).unwrap_err();
    assert_eq!(err.requested().get(), 5);
    assert_eq!(err.available(), 2);
  }

  #[test]
  fn test_truncate() {
    let data = vec![1, 2, 3, 4, 5];
    let mut buf = Bytes::from(data);

    buf.truncate(3);
    assert_eq!(buf.remaining(), 3);
    assert_eq!(buf.buffer(), &[1, 2, 3]);

    // Truncating to larger size has no effect
    buf.truncate(10);
    assert_eq!(buf.remaining(), 3);
  }

  #[test]
  fn test_segment() {
    let data = b"Hello, World!".to_vec();
    let buf = Bytes::from(data);

    let hello = buf.segment(0..5);
    assert_eq!(hello.buffer(), b"Hello");

    let world = buf.segment(7..12);
    assert_eq!(world.buffer(), b"World");

    // Original unchanged
    assert_eq!(buf.remaining(), 13);
  }

  #[allow(clippy::reversed_empty_ranges)]
  #[test]
  fn test_try_segment() {
    let data = vec![1, 2, 3, 4, 5];
    let buf = Bytes::from(data);

    assert!(buf.try_segment(1..4).is_ok());
    assert!(buf.try_segment(0..10).is_err());
    assert!(buf.try_segment(3..2).is_err()); // Invalid range
  }

  #[test]
  fn test_split_off() {
    let data = vec![1, 2, 3, 4, 5];
    let mut buf = Bytes::from(data);

    let tail = buf.split_off(2);
    assert_eq!(buf.buffer(), &[1, 2]);
    assert_eq!(tail.buffer(), &[3, 4, 5]);
  }

  #[test]
  fn test_split_to() {
    let data = vec![1, 2, 3, 4, 5];
    let mut buf = Bytes::from(data);

    let head = buf.split_to(2);
    assert_eq!(head.buffer(), &[1, 2]);
    assert_eq!(buf.buffer(), &[3, 4, 5]);
  }

  #[test]
  fn test_peek_primitives() {
    let data = vec![0x12, 0x34, 0x56, 0x78, 0x9A, 0xBC, 0xDE, 0xF0];
    let buf = Bytes::from(data);

    // Peek doesn't advance
    assert_eq!(buf.peek_u8(), 0x12);
    assert_eq!(buf.remaining(), 8);

    assert_eq!(buf.peek_u16_le(), 0x3412);
    assert_eq!(buf.peek_u16_be(), 0x1234);

    assert_eq!(buf.peek_u32_le(), 0x78563412);
    assert_eq!(buf.peek_u32_be(), 0x12345678);

    // Chunk unchanged
    assert_eq!(buf.remaining(), 8);
  }

  #[test]
  fn test_read_primitives() {
    let data = vec![0x12, 0x34, 0x56, 0x78, 0x9A, 0xBC, 0xDE, 0xF0];
    let mut buf = Bytes::from(data);

    assert_eq!(buf.read_u8(), 0x12);
    assert_eq!(buf.remaining(), 7);

    assert_eq!(buf.read_u16_le(), 0x5634);
    assert_eq!(buf.remaining(), 5);

    assert_eq!(buf.read_u32_be(), 0x789ABCDE);
    assert_eq!(buf.remaining(), 1);

    assert_eq!(buf.read_u8(), 0xF0);
    assert_eq!(buf.remaining(), 0);
  }

  #[test]
  fn test_peek_checked() {
    let data = vec![0x12];
    let buf = Bytes::from(data);

    assert_eq!(buf.peek_u8_checked(), Some(0x12));
    assert_eq!(buf.peek_u16_le_checked(), None);
    assert_eq!(buf.peek_u32_be_checked(), None);
  }

  #[test]
  fn test_read_checked() {
    let data = vec![0x12, 0x34];
    let mut buf = Bytes::from(data);

    assert_eq!(buf.read_u8_checked(), Some(0x12));
    assert_eq!(buf.read_u16_le_checked(), None); // Only 1 byte left
    assert_eq!(buf.remaining(), 1); // Read failed, cursor unchanged

    assert_eq!(buf.read_u8_checked(), Some(0x34));
    assert_eq!(buf.remaining(), 0);
  }

  #[test]
  fn test_try_methods() {
    let data = vec![0x12, 0x34];
    let mut buf = Bytes::from(data);

    assert!(buf.try_peek_u16_le().is_ok());

    let err = buf.try_peek_u32_le().unwrap_err();
    assert_eq!(err.requested().get(), 4);
    assert_eq!(err.available(), 2);

    assert!(buf.try_read_u16_be().is_ok());
    assert_eq!(buf.remaining(), 0);

    let err = buf.try_read_u8().unwrap_err();
    assert_eq!(err.requested().get(), 1);
    assert_eq!(err.available(), 0);
  }

  #[test]
  fn test_arrays() {
    let data = vec![1, 2, 3, 4, 5, 6, 7, 8];
    let mut buf = Bytes::from(data);

    let arr: [u8; 3] = buf.peek_array();
    assert_eq!(arr, [1, 2, 3]);
    assert_eq!(buf.remaining(), 8);

    let arr: [u8; 3] = buf.read_array();
    assert_eq!(arr, [1, 2, 3]);
    assert_eq!(buf.remaining(), 5);

    assert!(buf.peek_array_checked::<10>().is_none());
    assert!(buf.read_array_checked::<10>().is_none());
  }

  #[test]
  fn test_floating_point() {
    let data = vec![
      0x00, 0x00, 0x80, 0x3F, // 1.0f32 in little-endian
      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xF0, 0x3F, // 1.0f64 in little-endian
    ];
    let mut buf = Bytes::from(data);

    assert_eq!(buf.read_f32_le(), 1.0);
    assert_eq!(buf.read_f64_le(), 1.0);
    assert_eq!(buf.remaining(), 0);
  }

  #[test]
  fn test_to_vec() {
    let data = vec![1, 2, 3, 4, 5];
    let mut buf = Bytes::from(data);

    buf.advance(2);
    let vec = buf.to_vec();
    assert_eq!(vec, vec![3, 4, 5]);
  }

  #[test]
  fn test_to_bytes() {
    let data = vec![1, 2, 3, 4, 5];
    let mut buf = Bytes::from(data.clone());

    buf.advance(1);
    let bytes = buf.to_bytes();
    assert_eq!(bytes.as_ref(), &[2, 3, 4, 5]);

    // Original unchanged
    assert_eq!(buf.buffer(), &[2, 3, 4, 5]);
  }

  #[test]
  fn test_to_bytes_mut() {
    let data = vec![1, 2, 3, 4, 5];
    let mut buf = Bytes::from(data);

    buf.advance(1);
    let mut bytes_mut = buf.to_bytes_mut();
    bytes_mut[0] = 10;
    assert_eq!(bytes_mut.as_ref(), &[10, 3, 4, 5]);

    // Original unchanged
    assert_eq!(buf.buffer(), &[2, 3, 4, 5]);
  }

  #[test]
  fn test_bytes_specific_features() {
    let data = vec![1, 2, 3, 4, 5];
    let buf = Bytes::from(data);

    // Test zero-copy cloning
    let clone1 = buf.clone();
    let clone2 = buf.clone();

    assert_eq!(clone1.buffer(), clone2.buffer());
    assert_eq!(clone1.buffer(), buf.buffer());

    // Test slicing maintains reference counting
    let slice = buf.segment(1..4);
    assert_eq!(slice.buffer(), &[2, 3, 4]);
  }

  #[test]
  fn test_varint() {
    use varing::Varint as _;

    let mut data = vec![0; 10];

    // Encode a varint
    let encoded_len = 42u32.encode(&mut data).unwrap();
    let buf = Bytes::from(data);

    // Peek varint
    let (len, value) = buf.peek_varint::<u32>().unwrap();
    assert_eq!(value, 42);
    assert_eq!(len, encoded_len);
    assert_eq!(buf.remaining(), 10);

    // Read varint
    let mut buf = buf;
    let (len, value) = buf.read_varint::<u32>().unwrap();
    assert_eq!(value, 42);
    assert_eq!(len, encoded_len);
    assert_eq!(buf.remaining(), 10 - encoded_len.get());
  }

  #[test]
  fn test_segment_edge() {
    let empty = Bytes::new();
    let seg = empty.segment(..);
    assert_eq!(seg.remaining(), 0);

    let empty: &[u8] = &[];
    let seg = empty.segment(..);
    assert_eq!(seg.remaining(), 0);
  }

  #[test]
  fn test_try_segment_edge() {
    let empty = Bytes::new();
    let seg = empty.try_segment(..).unwrap();
    assert_eq!(seg.remaining(), 0);

    let empty: &[u8] = &[];
    let seg = empty.try_segment(..).unwrap();
    assert_eq!(seg.remaining(), 0);
  }

  #[test]
  #[should_panic]
  fn test_advance_panic_empty() {
    let empty = Bytes::new();
    let mut buf = empty;
    buf.advance(1); // Should panic
  }
}