-
Notifications
You must be signed in to change notification settings - Fork 15.4k
/
string.rs
1011 lines (899 loc) · 32.9 KB
/
string.rs
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
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
// Protocol Buffers - Google's data interchange format
// Copyright 2023 Google LLC. All rights reserved.
//
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file or at
// https://developers.google.com/open-source/licenses/bsd
//! Items specific to `bytes` and `string` fields.
#![allow(dead_code)]
#![allow(unused)]
use crate::__internal::{Private, PtrAndLen, RawMessage};
use crate::__runtime::{BytesAbsentMutData, BytesPresentMutData, InnerBytesMut};
use crate::macros::impl_forwarding_settable_value;
use crate::{
AbsentField, FieldEntry, Mut, MutProxy, Optional, PresentField, Proxied, ProxiedWithPresence,
SettableValue, View, ViewProxy,
};
use std::borrow::Cow;
use std::cmp::{Eq, Ord, Ordering, PartialEq, PartialOrd};
use std::convert::{AsMut, AsRef};
use std::fmt;
use std::hash::{Hash, Hasher};
use std::iter;
use std::ops::{Deref, DerefMut};
use utf8::Utf8Chunks;
/// A mutator for `bytes` fields - this type is `protobuf::Mut<'msg, [u8]>`.
///
/// This type implements `Deref<Target = [u8]>`, so many operations are
/// provided through that, including indexing and slicing.
///
/// Conceptually, this type is like a `&'msg mut &'msg str`, though the actual
/// implementation is dependent on runtime and `'msg` is covariant.
///
/// Unlike `Vec<u8>`, this type has no in-place concatenation functions like
/// `extend_from_slice`.
///
/// `BytesMut` is not intended to be grown and reallocated like a `Vec`. It's
/// recommended to instead build a `Vec<u8>` or `String` and pass that directly
/// to `set`, which will reuse the allocation if supported by the runtime.
#[derive(Debug)]
pub struct BytesMut<'msg> {
inner: InnerBytesMut<'msg>,
}
// SAFETY:
// - Protobuf Rust messages don't allow shared mutation across threads.
// - Protobuf Rust messages don't share arenas.
// - All access that touches an arena occurs behind a `&mut`.
// - All mutators that store an arena are `!Send`.
unsafe impl Sync for BytesMut<'_> {}
impl<'msg> BytesMut<'msg> {
/// Constructs a new `BytesMut` from its internal, runtime-dependent part.
#[doc(hidden)]
pub fn from_inner(_private: Private, inner: InnerBytesMut<'msg>) -> Self {
Self { inner }
}
/// Gets the current value of the field.
pub fn get(&self) -> &[u8] {
self.as_view()
}
/// Sets the byte string to the given `val`, cloning any borrowed data.
///
/// This method accepts both owned and borrowed byte strings; if the runtime
/// supports it, an owned value will not reallocate when setting the
/// string.
pub fn set(&mut self, val: impl SettableValue<[u8]>) {
val.set_on(Private, MutProxy::as_mut(self))
}
/// Truncates the byte string.
///
/// Has no effect if `new_len` is larger than the current `len`.
pub fn truncate(&mut self, new_len: usize) {
self.inner.truncate(new_len)
}
/// Clears the byte string to the empty string.
///
/// # Compared with `FieldEntry::clear`
///
/// Note that this is different than marking an `optional bytes` field as
/// absent; if these `bytes` are in an `optional`, `FieldEntry::is_set`
/// will still return `true` after this method is invoked.
///
/// This also means that if the field has a non-empty default,
/// `BytesMut::clear` results in the accessor returning an empty string
/// while `FieldEntry::clear` results in the non-empty default.
///
/// However, for a proto3 `bytes` that has implicit presence, there is no
/// distinction between these states: unset `bytes` is the same as empty
/// `bytes` and the default is always the empty string.
///
/// In the C++ API, this is the difference between `msg.clear_bytes_field()`
/// and `msg.mutable_bytes_field()->clear()`.
///
/// Having the same name and signature as `FieldEntry::clear` makes code
/// that calls `field_mut().clear()` easier to migrate from implicit
/// to explicit presence.
pub fn clear(&mut self) {
self.truncate(0);
}
}
impl Deref for BytesMut<'_> {
type Target = [u8];
fn deref(&self) -> &[u8] {
self.as_ref()
}
}
impl AsRef<[u8]> for BytesMut<'_> {
fn as_ref(&self) -> &[u8] {
unsafe { self.inner.get() }
}
}
impl Proxied for [u8] {
type View<'msg> = &'msg [u8];
type Mut<'msg> = BytesMut<'msg>;
}
impl ProxiedWithPresence for [u8] {
type PresentMutData<'msg> = BytesPresentMutData<'msg>;
type AbsentMutData<'msg> = BytesAbsentMutData<'msg>;
fn clear_present_field(present_mutator: Self::PresentMutData<'_>) -> Self::AbsentMutData<'_> {
present_mutator.clear()
}
fn set_absent_to_default(absent_mutator: Self::AbsentMutData<'_>) -> Self::PresentMutData<'_> {
absent_mutator.set_absent_to_default()
}
}
impl<'msg> ViewProxy<'msg> for &'msg [u8] {
type Proxied = [u8];
fn as_view(&self) -> &[u8] {
self
}
fn into_view<'shorter>(self) -> &'shorter [u8]
where
'msg: 'shorter,
{
self
}
}
impl<'msg> ViewProxy<'msg> for BytesMut<'msg> {
type Proxied = [u8];
fn as_view(&self) -> &[u8] {
self.as_ref()
}
fn into_view<'shorter>(self) -> &'shorter [u8]
where
'msg: 'shorter,
{
self.inner.get()
}
}
impl<'msg> MutProxy<'msg> for BytesMut<'msg> {
fn as_mut(&mut self) -> BytesMut<'_> {
BytesMut { inner: self.inner }
}
fn into_mut<'shorter>(self) -> BytesMut<'shorter>
where
'msg: 'shorter,
{
BytesMut { inner: self.inner }
}
}
impl SettableValue<[u8]> for &'_ [u8] {
fn set_on<'msg>(self, _private: Private, mutator: Mut<'msg, [u8]>)
where
[u8]: 'msg,
{
// SAFETY: this is a `bytes` field with no restriction on UTF-8.
unsafe { mutator.inner.set(self) }
}
fn set_on_absent(
self,
_private: Private,
absent_mutator: <[u8] as ProxiedWithPresence>::AbsentMutData<'_>,
) -> <[u8] as ProxiedWithPresence>::PresentMutData<'_> {
// SAFETY: this is a `bytes` field with no restriction on UTF-8.
unsafe { absent_mutator.set(self) }
}
fn set_on_present(
self,
_private: Private,
present_mutator: <[u8] as ProxiedWithPresence>::PresentMutData<'_>,
) {
// SAFETY: this is a `bytes` field with no restriction on UTF-8.
unsafe {
present_mutator.set(self);
}
}
}
impl<const N: usize> SettableValue<[u8]> for &'_ [u8; N] {
// forward to `self[..]`
impl_forwarding_settable_value!([u8], self => &self[..]);
}
impl SettableValue<[u8]> for Vec<u8> {
// TODO: Investigate taking ownership of this when allowed by the
// runtime.
impl_forwarding_settable_value!([u8], self => &self[..]);
}
impl SettableValue<[u8]> for Cow<'_, [u8]> {
// TODO: Investigate taking ownership of this when allowed by the
// runtime.
impl_forwarding_settable_value!([u8], self => &self[..]);
}
impl Hash for BytesMut<'_> {
fn hash<H: Hasher>(&self, state: &mut H) {
self.deref().hash(state)
}
}
impl Eq for BytesMut<'_> {}
impl<'msg> Ord for BytesMut<'msg> {
fn cmp(&self, other: &BytesMut<'msg>) -> Ordering {
self.deref().cmp(other.deref())
}
}
/// The bytes were not valid UTF-8.
#[derive(Debug, PartialEq)]
pub struct Utf8Error(pub(crate) ());
impl From<std::str::Utf8Error> for Utf8Error {
fn from(_: std::str::Utf8Error) -> Utf8Error {
Utf8Error(())
}
}
/// A shared immutable view of a protobuf `string` field's contents.
///
/// Like a `str`, it can be cheaply accessed as bytes and
/// is dynamically sized, requiring it be accessed through a pointer.
///
/// # UTF-8 and `&str` access
///
/// Protobuf [docs] state that a `string` field contains UTF-8 encoded text.
/// However, not every runtime enforces this, and the Rust runtime is designed
/// to integrate with other runtimes with FFI, like C++.
///
/// Because of this, in order to access the contents as a `&str`, users must
/// call [`ProtoStr::to_str`] to perform a (possibly runtime-elided) UTF-8
/// validation check. However, the Rust API only allows `set()`ting a `string`
/// field with data should be valid UTF-8 like a `&str` or a
/// `&ProtoStr`. This means that this check should rarely fail, but is necessary
/// to prevent UB when interacting with C++, which has looser restrictions.
///
/// Most of the time, users should not perform direct `&str` access to the
/// contents - this type implements `Display` and comparison with `str`,
/// so it's best to avoid a UTF-8 check by working directly with `&ProtoStr`
/// or converting to `&[u8]`.
///
/// # `Display` and `ToString`
/// `ProtoStr` is ordinarily UTF-8 and so implements `Display`. If there are
/// any invalid UTF-8 sequences, they are replaced with [`U+FFFD REPLACEMENT
/// CHARACTER`]. Because anything implementing `Display` also implements
/// `ToString`, `proto_str.to_string()` is equivalent to
/// `String::from_utf8_lossy(proto_str.as_bytes()).into_owned()`.
///
/// [docs]: https://protobuf.dev/programming-guides/proto2/#scalar
/// [dst]: https://doc.rust-lang.org/reference/dynamically-sized-types.html
/// [`U+FFFD REPLACEMENT CHARACTER`]: std::char::REPLACEMENT_CHARACTER
#[repr(transparent)]
pub struct ProtoStr([u8]);
impl ProtoStr {
/// Converts `self` to a byte slice.
///
/// Note: this type does not implement `Deref`; you must call `as_bytes()`
/// or `AsRef<[u8]>` to get access to bytes.
pub fn as_bytes(&self) -> &[u8] {
&self.0
}
/// Yields a `&str` slice if `self` contains valid UTF-8.
///
/// This may perform a runtime check, dependent on runtime.
///
/// `String::from_utf8_lossy(proto_str.as_bytes())` can be used to
/// infallibly construct a string, replacing invalid UTF-8 with
/// [`U+FFFD REPLACEMENT CHARACTER`].
///
/// [`U+FFFD REPLACEMENT CHARACTER`]: std::char::REPLACEMENT_CHARACTER
// This is not `try_to_str` since `to_str` is shorter, with `CStr` as precedent.
pub fn to_str(&self) -> Result<&str, Utf8Error> {
Ok(std::str::from_utf8(&self.0)?)
}
/// Converts `self` to a string, including invalid characters.
///
/// Invalid UTF-8 sequences are replaced with
/// [`U+FFFD REPLACEMENT CHARACTER`].
///
/// Users should be prefer this to `.to_string()` provided by `Display`.
/// `.to_cow_lossy()` is the same operation, but it may avoid an
/// allocation if the string is already UTF-8.
///
/// [`U+FFFD REPLACEMENT CHARACTER`]: std::char::REPLACEMENT_CHARACTER
//
// This method is named `to_string_lossy` in `CStr`, but since `to_string`
// also exists on this type, this name was chosen to avoid confusion.
pub fn to_cow_lossy(&self) -> Cow<'_, str> {
String::from_utf8_lossy(&self.0)
}
/// Returns `true` if `self` has a length of zero bytes.
pub fn is_empty(&self) -> bool {
self.0.is_empty()
}
/// Returns the length of `self`.
///
/// Like `&str`, this is a length in bytes, not `char`s or graphemes.
pub fn len(&self) -> usize {
self.0.len()
}
/// Iterates over the `char`s in this protobuf `string`.
///
/// Invalid UTF-8 sequences are replaced with
/// [`U+FFFD REPLACEMENT CHARACTER`].
///
/// [`U+FFFD REPLACEMENT CHARACTER`]: std::char::REPLACEMENT_CHARACTER
pub fn chars(&self) -> impl Iterator<Item = char> + '_ + fmt::Debug {
Utf8Chunks::new(self.as_bytes()).flat_map(|chunk| {
let mut yield_replacement_char = !chunk.invalid().is_empty();
chunk.valid().chars().chain(iter::from_fn(move || {
// Yield a single replacement character for every
// non-empty invalid sequence.
yield_replacement_char.then(|| {
yield_replacement_char = false;
char::REPLACEMENT_CHARACTER
})
}))
})
}
/// Returns an iterator over chunks of UTF-8 data in the string.
///
/// An `Ok(&str)` is yielded for every valid UTF-8 chunk, and an
/// `Err(&[u8])` for each non-UTF-8 chunk. An `Err` will be emitted
/// multiple times in a row for contiguous invalid chunks. Each invalid
/// chunk in an `Err` has a maximum length of 3 bytes.
pub fn utf8_chunks(&self) -> impl Iterator<Item = Result<&str, &[u8]>> + '_ {
Utf8Chunks::new(self.as_bytes()).flat_map(|chunk| {
let valid = chunk.valid();
let invalid = chunk.invalid();
(!valid.is_empty())
.then_some(Ok(valid))
.into_iter()
.chain((!invalid.is_empty()).then_some(Err(invalid)))
})
}
/// Converts known-UTF-8 bytes to a `ProtoStr` without a check.
///
/// # Safety
/// `bytes` must be valid UTF-8 if the current runtime requires it.
pub unsafe fn from_utf8_unchecked(bytes: &[u8]) -> &Self {
// SAFETY:
// - `ProtoStr` is `#[repr(transparent)]` over `[u8]`, so it has the same
// layout.
// - `ProtoStr` has the same pointer metadata and element size as `[u8]`.
unsafe { &*(bytes as *const [u8] as *const Self) }
}
/// Interprets a string slice as a `&ProtoStr`.
pub fn from_str(string: &str) -> &Self {
// SAFETY: `string.as_bytes()` is valid UTF-8.
unsafe { Self::from_utf8_unchecked(string.as_bytes()) }
}
}
impl AsRef<[u8]> for ProtoStr {
fn as_ref(&self) -> &[u8] {
self.as_bytes()
}
}
impl<'msg> From<&'msg ProtoStr> for &'msg [u8] {
fn from(val: &'msg ProtoStr) -> &'msg [u8] {
val.as_bytes()
}
}
impl<'msg> From<&'msg str> for &'msg ProtoStr {
fn from(val: &'msg str) -> &'msg ProtoStr {
ProtoStr::from_str(val)
}
}
impl<'msg> TryFrom<&'msg ProtoStr> for &'msg str {
type Error = Utf8Error;
fn try_from(val: &'msg ProtoStr) -> Result<&'msg str, Utf8Error> {
val.to_str()
}
}
impl<'msg> TryFrom<&'msg [u8]> for &'msg ProtoStr {
type Error = Utf8Error;
fn try_from(val: &'msg [u8]) -> Result<&'msg ProtoStr, Utf8Error> {
Ok(ProtoStr::from_str(std::str::from_utf8(val)?))
}
}
impl fmt::Debug for ProtoStr {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
fmt::Debug::fmt(&Utf8Chunks::new(self.as_bytes()).debug(), f)
}
}
impl fmt::Display for ProtoStr {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
use std::fmt::Write as _;
for chunk in Utf8Chunks::new(self.as_bytes()) {
fmt::Display::fmt(chunk.valid(), f)?;
if !chunk.invalid().is_empty() {
// One invalid chunk is emitted per detected invalid sequence.
f.write_char(char::REPLACEMENT_CHARACTER)?;
}
}
Ok(())
}
}
impl Hash for ProtoStr {
fn hash<H: Hasher>(&self, state: &mut H) {
self.as_bytes().hash(state)
}
}
impl Eq for ProtoStr {}
impl Ord for ProtoStr {
fn cmp(&self, other: &ProtoStr) -> Ordering {
self.as_bytes().cmp(other.as_bytes())
}
}
impl Proxied for ProtoStr {
type View<'msg> = &'msg ProtoStr;
type Mut<'msg> = ProtoStrMut<'msg>;
}
impl ProxiedWithPresence for ProtoStr {
type PresentMutData<'msg> = StrPresentMutData<'msg>;
type AbsentMutData<'msg> = StrAbsentMutData<'msg>;
fn clear_present_field(present_mutator: Self::PresentMutData<'_>) -> Self::AbsentMutData<'_> {
StrAbsentMutData(present_mutator.0.clear())
}
fn set_absent_to_default(absent_mutator: Self::AbsentMutData<'_>) -> Self::PresentMutData<'_> {
StrPresentMutData(absent_mutator.0.set_absent_to_default())
}
}
impl<'msg> ViewProxy<'msg> for &'msg ProtoStr {
type Proxied = ProtoStr;
fn as_view(&self) -> &ProtoStr {
self
}
fn into_view<'shorter>(self) -> &'shorter ProtoStr
where
'msg: 'shorter,
{
self
}
}
/// Non-exported newtype for `ProxiedWithPresence::PresentData`
#[derive(Debug)]
pub struct StrPresentMutData<'msg>(BytesPresentMutData<'msg>);
impl<'msg> ViewProxy<'msg> for StrPresentMutData<'msg> {
type Proxied = ProtoStr;
fn as_view(&self) -> View<'_, ProtoStr> {
// SAFETY: The `ProtoStr` API guards against non-UTF-8 data. The runtime does
// not require `ProtoStr` to be UTF-8 if it could be mutated outside of these
// guards, such as through FFI.
unsafe { ProtoStr::from_utf8_unchecked(self.0.as_view()) }
}
fn into_view<'shorter>(self) -> View<'shorter, ProtoStr>
where
'msg: 'shorter,
{
// SAFETY: The `ProtoStr` API guards against non-UTF-8 data. The runtime does
// not require `ProtoStr` to be UTF-8 if it could be mutated outside of these
// guards, such as through FFI.
unsafe { ProtoStr::from_utf8_unchecked(self.0.into_view()) }
}
}
impl<'msg> MutProxy<'msg> for StrPresentMutData<'msg> {
fn as_mut(&mut self) -> Mut<'_, ProtoStr> {
ProtoStrMut { bytes: self.0.as_mut() }
}
fn into_mut<'shorter>(self) -> Mut<'shorter, ProtoStr>
where
'msg: 'shorter,
{
ProtoStrMut { bytes: self.0.into_mut() }
}
}
/// Non-exported newtype for `ProxiedWithPresence::AbsentData`
#[derive(Debug)]
pub struct StrAbsentMutData<'msg>(BytesAbsentMutData<'msg>);
impl<'msg> ViewProxy<'msg> for StrAbsentMutData<'msg> {
type Proxied = ProtoStr;
fn as_view(&self) -> View<'_, ProtoStr> {
// SAFETY: The `ProtoStr` API guards against non-UTF-8 data. The runtime does
// not require `ProtoStr` to be UTF-8 if it could be mutated outside of these
// guards, such as through FFI.
unsafe { ProtoStr::from_utf8_unchecked(self.0.as_view()) }
}
fn into_view<'shorter>(self) -> View<'shorter, ProtoStr>
where
'msg: 'shorter,
{
// SAFETY: The `ProtoStr` API guards against non-UTF-8 data. The runtime does
// not require `ProtoStr` to be UTF-8 if it could be mutated outside of these
// guards, such as through FFI.
unsafe { ProtoStr::from_utf8_unchecked(self.0.into_view()) }
}
}
#[derive(Debug)]
pub struct ProtoStrMut<'msg> {
bytes: BytesMut<'msg>,
}
impl<'msg> ProtoStrMut<'msg> {
/// Constructs a new `ProtoStrMut` from its internal, runtime-dependent
/// part.
#[doc(hidden)]
pub fn from_inner(_private: Private, inner: InnerBytesMut<'msg>) -> Self {
Self { bytes: BytesMut { inner } }
}
/// Converts a `bytes` `FieldEntry` into a `string` one. Used by gencode.
#[doc(hidden)]
pub fn field_entry_from_bytes(
_private: Private,
field_entry: FieldEntry<'_, [u8]>,
) -> FieldEntry<ProtoStr> {
match field_entry {
Optional::Set(present) => {
Optional::Set(PresentField::from_inner(Private, StrPresentMutData(present.inner)))
}
Optional::Unset(absent) => {
Optional::Unset(AbsentField::from_inner(Private, StrAbsentMutData(absent.inner)))
}
}
}
/// Gets the current value of the field.
pub fn get(&self) -> &ProtoStr {
self.as_view()
}
/// Sets the string to the given `val`, cloning any borrowed data.
///
/// This method accepts both owned and borrowed strings; if the runtime
/// supports it, an owned value will not reallocate when setting the
/// string.
pub fn set(&mut self, val: impl SettableValue<ProtoStr>) {
val.set_on(Private, MutProxy::as_mut(self))
}
/// Truncates the string.
///
/// Has no effect if `new_len` is larger than the current `len`.
///
/// If `new_len` does not lie on a UTF-8 `char` boundary, behavior is
/// runtime-dependent. If this occurs, the runtime may:
///
/// - Panic
/// - Truncate the string further to be on a `char` boundary.
/// - Truncate to `new_len`, resulting in a `ProtoStr` with a non-UTF8 tail.
pub fn truncate(&mut self, new_len: usize) {
self.bytes.truncate(new_len)
}
/// Clears the string, setting it to the empty string.
///
/// # Compared with `FieldEntry::clear`
///
/// Note that this is different than marking an `optional string` field as
/// absent; if this cleared `string` is in an `optional`,
/// `FieldEntry::is_set` will still return `true` after this method is
/// invoked.
///
/// This also means that if the field has a non-empty default,
/// `ProtoStrMut::clear` results in the accessor returning an empty string
/// while `FieldEntry::clear` results in the non-empty default.
///
/// However, for a proto3 `string` that has implicit presence, there is no
/// distinction between these states: unset `string` is the same as empty
/// `string` and the default is always the empty string.
///
/// In the C++ API, this is the difference between
/// `msg.clear_string_field()`
/// and `msg.mutable_string_field()->clear()`.
///
/// Having the same name and signature as `FieldEntry::clear` makes code
/// that calls `field_mut().clear()` easier to migrate from implicit
/// to explicit presence.
pub fn clear(&mut self) {
self.truncate(0);
}
}
impl Deref for ProtoStrMut<'_> {
type Target = ProtoStr;
fn deref(&self) -> &ProtoStr {
self.as_view()
}
}
impl AsRef<ProtoStr> for ProtoStrMut<'_> {
fn as_ref(&self) -> &ProtoStr {
self.as_view()
}
}
impl AsRef<[u8]> for ProtoStrMut<'_> {
fn as_ref(&self) -> &[u8] {
self.as_view().as_bytes()
}
}
impl<'msg> ViewProxy<'msg> for ProtoStrMut<'msg> {
type Proxied = ProtoStr;
fn as_view(&self) -> &ProtoStr {
// SAFETY: The `ProtoStr` API guards against non-UTF-8 data. The runtime does
// not require `ProtoStr` to be UTF-8 if it could be mutated outside of these
// guards, such as through FFI.
unsafe { ProtoStr::from_utf8_unchecked(self.bytes.as_view()) }
}
fn into_view<'shorter>(self) -> &'shorter ProtoStr
where
'msg: 'shorter,
{
unsafe { ProtoStr::from_utf8_unchecked(self.bytes.into_view()) }
}
}
impl<'msg> MutProxy<'msg> for ProtoStrMut<'msg> {
fn as_mut(&mut self) -> ProtoStrMut<'_> {
ProtoStrMut { bytes: BytesMut { inner: self.bytes.inner } }
}
fn into_mut<'shorter>(self) -> ProtoStrMut<'shorter>
where
'msg: 'shorter,
{
ProtoStrMut { bytes: BytesMut { inner: self.bytes.inner } }
}
}
impl SettableValue<ProtoStr> for &'_ ProtoStr {
fn set_on<'b>(self, _private: Private, mutator: Mut<'b, ProtoStr>)
where
ProtoStr: 'b,
{
// SAFETY: A `ProtoStr` has the same UTF-8 validity requirement as the runtime.
unsafe { mutator.bytes.inner.set(self.as_bytes()) }
}
fn set_on_absent(
self,
_private: Private,
absent_mutator: <ProtoStr as ProxiedWithPresence>::AbsentMutData<'_>,
) -> <ProtoStr as ProxiedWithPresence>::PresentMutData<'_> {
// SAFETY: A `ProtoStr` has the same UTF-8 validity requirement as the runtime.
StrPresentMutData(unsafe { absent_mutator.0.set(self.as_bytes()) })
}
fn set_on_present(
self,
_private: Private,
present_mutator: <ProtoStr as ProxiedWithPresence>::PresentMutData<'_>,
) {
// SAFETY: A `ProtoStr` has the same UTF-8 validity requirement as the runtime.
unsafe {
present_mutator.0.set(self.as_bytes());
}
}
}
impl SettableValue<ProtoStr> for &'_ str {
impl_forwarding_settable_value!(ProtoStr, self => ProtoStr::from_str(self));
}
impl SettableValue<ProtoStr> for String {
// TODO: Investigate taking ownership of this when allowed by the
// runtime.
impl_forwarding_settable_value!(ProtoStr, self => ProtoStr::from_str(&self));
}
impl SettableValue<ProtoStr> for Cow<'_, str> {
// TODO: Investigate taking ownership of this when allowed by the
// runtime.
impl_forwarding_settable_value!(ProtoStr, self => ProtoStr::from_str(&self));
}
impl Hash for ProtoStrMut<'_> {
fn hash<H: Hasher>(&self, state: &mut H) {
self.deref().hash(state)
}
}
impl Eq for ProtoStrMut<'_> {}
impl<'msg> Ord for ProtoStrMut<'msg> {
fn cmp(&self, other: &ProtoStrMut<'msg>) -> Ordering {
self.deref().cmp(other.deref())
}
}
/// Implements `PartialCmp` and `PartialEq` for the `lhs` against the `rhs`
/// using `AsRef<[u8]>`.
// TODO: consider improving to not require a `<()>` if no generics are
// needed
macro_rules! impl_bytes_partial_cmp {
($(<($($generics:tt)*)> $lhs:ty => $rhs:ty),+ $(,)?) => {
$(
impl<$($generics)*> PartialEq<$rhs> for $lhs {
fn eq(&self, other: &$rhs) -> bool {
AsRef::<[u8]>::as_ref(self) == AsRef::<[u8]>::as_ref(other)
}
}
impl<$($generics)*> PartialOrd<$rhs> for $lhs {
fn partial_cmp(&self, other: &$rhs) -> Option<Ordering> {
AsRef::<[u8]>::as_ref(self).partial_cmp(AsRef::<[u8]>::as_ref(other))
}
}
)*
};
}
impl_bytes_partial_cmp!(
// Should `BytesMut` compare with `str` and `ProtoStr[Mut]` with `[u8]`?
// `[u8]` and `str` do not compare with each other in the stdlib.
// `BytesMut` against protobuf types
<('a, 'b)> BytesMut<'a> => BytesMut<'b>,
// `BytesMut` against foreign types
<('a)> BytesMut<'a> => [u8],
<('a)> [u8] => BytesMut<'a>,
<('a, const N: usize)> BytesMut<'a> => [u8; N],
<('a, const N: usize)> [u8; N] => BytesMut<'a>,
// `ProtoStr` against protobuf types
<()> ProtoStr => ProtoStr,
<('a)> ProtoStr => ProtoStrMut<'a>,
// `ProtoStr` against foreign types
<()> ProtoStr => str,
<()> str => ProtoStr,
// `ProtoStrMut` against protobuf types
<('a, 'b)> ProtoStrMut<'a> => ProtoStrMut<'b>,
<('a)> ProtoStrMut<'a> => ProtoStr,
// `ProtoStrMut` against foreign types
<('a)> ProtoStrMut<'a> => str,
<('a)> str => ProtoStrMut<'a>,
);
#[cfg(test)]
mod tests {
use super::*;
// TODO: Add unit tests
// Shorter and safe utility function to construct `ProtoStr` from bytes for
// testing.
fn test_proto_str(bytes: &[u8]) -> &ProtoStr {
// SAFETY: The runtime that this test executes under does not elide UTF-8 checks
// inside of `ProtoStr`.
unsafe { ProtoStr::from_utf8_unchecked(bytes) }
}
// UTF-8 test cases copied from:
// https://github.com/rust-lang/rust/blob/e8ee0b7/library/core/tests/str_lossy.rs
#[test]
fn proto_str_debug() {
assert_eq!(&format!("{:?}", test_proto_str(b"Hello There")), "\"Hello There\"");
assert_eq!(
&format!(
"{:?}",
test_proto_str(b"Hello\xC0\x80 There\xE6\x83 Goodbye\xf4\x8d\x93\xaa"),
),
"\"Hello\\xC0\\x80 There\\xE6\\x83 Goodbye\\u{10d4ea}\"",
);
}
#[test]
fn proto_str_display() {
assert_eq!(&test_proto_str(b"Hello There").to_string(), "Hello There");
assert_eq!(
&test_proto_str(b"Hello\xC0\x80 There\xE6\x83 Goodbye\xf4\x8d\x93\xaa").to_string(),
"Hello�� There� Goodbye\u{10d4ea}",
);
}
#[test]
fn proto_str_to_rust_str() {
assert_eq!(test_proto_str(b"hello").to_str(), Ok("hello"));
assert_eq!(test_proto_str("ศไทย中华Việt Nam".as_bytes()).to_str(), Ok("ศไทย中华Việt Nam"));
for expect_fail in [
&b"Hello\xC2 There\xFF Goodbye"[..],
b"Hello\xC0\x80 There\xE6\x83 Goodbye",
b"\xF5foo\xF5\x80bar",
b"\xF1foo\xF1\x80bar\xF1\x80\x80baz",
b"\xF4foo\xF4\x80bar\xF4\xBFbaz",
b"\xF0\x80\x80\x80foo\xF0\x90\x80\x80bar",
b"\xED\xA0\x80foo\xED\xBF\xBFbar",
] {
assert_eq!(test_proto_str(expect_fail).to_str(), Err(Utf8Error(())), "{expect_fail:?}");
}
}
#[test]
fn proto_str_to_cow() {
assert_eq!(test_proto_str(b"hello").to_cow_lossy(), Cow::Borrowed("hello"));
assert_eq!(
test_proto_str("ศไทย中华Việt Nam".as_bytes()).to_cow_lossy(),
Cow::Borrowed("ศไทย中华Việt Nam")
);
for (bytes, lossy_str) in [
(&b"Hello\xC2 There\xFF Goodbye"[..], "Hello� There� Goodbye"),
(b"Hello\xC0\x80 There\xE6\x83 Goodbye", "Hello�� There� Goodbye"),
(b"\xF5foo\xF5\x80bar", "�foo��bar"),
(b"\xF1foo\xF1\x80bar\xF1\x80\x80baz", "�foo�bar�baz"),
(b"\xF4foo\xF4\x80bar\xF4\xBFbaz", "�foo�bar��baz"),
(b"\xF0\x80\x80\x80foo\xF0\x90\x80\x80bar", "����foo\u{10000}bar"),
(b"\xED\xA0\x80foo\xED\xBF\xBFbar", "���foo���bar"),
] {
let cow = test_proto_str(bytes).to_cow_lossy();
assert!(matches!(cow, Cow::Owned(_)));
assert_eq!(&*cow, lossy_str, "{bytes:?}");
}
}
#[test]
fn proto_str_utf8_chunks() {
macro_rules! assert_chunks {
($bytes:expr, $($chunks:expr),* $(,)?) => {
let bytes = $bytes;
let chunks: &[Result<&str, &[u8]>] = &[$($chunks),*];
let s = test_proto_str(bytes);
let mut got_chunks = s.utf8_chunks();
let mut expected_chars = chunks.iter().copied();
assert!(got_chunks.eq(expected_chars), "{bytes:?} -> {chunks:?}");
};
}
assert_chunks!(b"hello", Ok("hello"));
assert_chunks!("ศไทย中华Việt Nam".as_bytes(), Ok("ศไทย中华Việt Nam"));
assert_chunks!(
b"Hello\xC2 There\xFF Goodbye",
Ok("Hello"),
Err(b"\xC2"),
Ok(" There"),
Err(b"\xFF"),
Ok(" Goodbye"),
);
assert_chunks!(
b"Hello\xC0\x80 There\xE6\x83 Goodbye",
Ok("Hello"),
Err(b"\xC0"),
Err(b"\x80"),
Ok(" There"),
Err(b"\xE6\x83"),
Ok(" Goodbye"),
);
assert_chunks!(
b"\xF5foo\xF5\x80bar",
Err(b"\xF5"),
Ok("foo"),
Err(b"\xF5"),
Err(b"\x80"),
Ok("bar"),
);
assert_chunks!(
b"\xF1foo\xF1\x80bar\xF1\x80\x80baz",
Err(b"\xF1"),
Ok("foo"),
Err(b"\xF1\x80"),
Ok("bar"),
Err(b"\xF1\x80\x80"),
Ok("baz"),
);
assert_chunks!(
b"\xF4foo\xF4\x80bar\xF4\xBFbaz",
Err(b"\xF4"),
Ok("foo"),
Err(b"\xF4\x80"),
Ok("bar"),
Err(b"\xF4"),
Err(b"\xBF"),
Ok("baz"),
);
assert_chunks!(
b"\xF0\x80\x80\x80foo\xF0\x90\x80\x80bar",
Err(b"\xF0"),
Err(b"\x80"),
Err(b"\x80"),
Err(b"\x80"),
Ok("foo\u{10000}bar"),
);
assert_chunks!(
b"\xED\xA0\x80foo\xED\xBF\xBFbar",
Err(b"\xED"),
Err(b"\xA0"),
Err(b"\x80"),
Ok("foo"),
Err(b"\xED"),
Err(b"\xBF"),
Err(b"\xBF"),
Ok("bar"),
);
}
#[test]
fn proto_str_chars() {
macro_rules! assert_chars {
($bytes:expr, $chars:expr) => {
let bytes = $bytes;
let chars = $chars;
let s = test_proto_str(bytes);
let mut got_chars = s.chars();
let mut expected_chars = chars.into_iter();
assert!(got_chars.eq(expected_chars), "{bytes:?} -> {chars:?}");
};
}
assert_chars!(b"hello", ['h', 'e', 'l', 'l', 'o']);
assert_chars!(
"ศไทย中华Việt Nam".as_bytes(),
['ศ', 'ไ', 'ท', 'ย', '中', '华', 'V', 'i', 'ệ', 't', ' ', 'N', 'a', 'm']
);
assert_chars!(
b"Hello\xC2 There\xFF Goodbye",
[
'H', 'e', 'l', 'l', 'o', '�', ' ', 'T', 'h', 'e', 'r', 'e', '�', ' ', 'G', 'o',
'o', 'd', 'b', 'y', 'e'
]
);
assert_chars!(
b"Hello\xC0\x80 There\xE6\x83 Goodbye",
[
'H', 'e', 'l', 'l', 'o', '�', '�', ' ', 'T', 'h', 'e', 'r', 'e', '�', ' ', 'G',
'o', 'o', 'd', 'b', 'y', 'e'
]
);
assert_chars!(b"\xF5foo\xF5\x80bar", ['�', 'f', 'o', 'o', '�', '�', 'b', 'a', 'r']);
assert_chars!(
b"\xF1foo\xF1\x80bar\xF1\x80\x80baz",
['�', 'f', 'o', 'o', '�', 'b', 'a', 'r', '�', 'b', 'a', 'z']
);
assert_chars!(
b"\xF4foo\xF4\x80bar\xF4\xBFbaz",
['�', 'f', 'o', 'o', '�', 'b', 'a', 'r', '�', '�', 'b', 'a', 'z']