-
-
Notifications
You must be signed in to change notification settings - Fork 1k
/
arg.rs
5345 lines (5106 loc) · 180 KB
/
arg.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
#![allow(deprecated)]
// Std
use std::{
borrow::Cow,
cmp::{Ord, Ordering},
error::Error,
ffi::OsStr,
fmt::{self, Display, Formatter},
str,
sync::{Arc, Mutex},
};
#[cfg(feature = "env")]
use std::{env, ffi::OsString};
#[cfg(feature = "yaml")]
use yaml_rust::Yaml;
// Internal
use crate::builder::usage_parser::UsageParser;
use crate::builder::ArgPredicate;
use crate::util::{Id, Key};
use crate::ArgAction;
use crate::PossibleValue;
use crate::ValueHint;
use crate::INTERNAL_ERROR_MSG;
use crate::{ArgFlags, ArgSettings};
#[cfg(feature = "regex")]
use crate::builder::RegexRef;
/// The abstract representation of a command line argument. Used to set all the options and
/// relationships that define a valid argument for the program.
///
/// There are two methods for constructing [`Arg`]s, using the builder pattern and setting options
/// manually, or using a usage string which is far less verbose but has fewer options. You can also
/// use a combination of the two methods to achieve the best of both worlds.
///
/// - [Basic API][crate::Arg#basic-api]
/// - [Value Handling][crate::Arg#value-handling]
/// - [Help][crate::Arg#help-1]
/// - [Advanced Argument Relations][crate::Arg#advanced-argument-relations]
/// - [Reflection][crate::Arg#reflection]
///
/// # Examples
///
/// ```rust
/// # use clap::{Arg, arg};
/// // Using the traditional builder pattern and setting each option manually
/// let cfg = Arg::new("config")
/// .short('c')
/// .long("config")
/// .takes_value(true)
/// .value_name("FILE")
/// .help("Provides a config file to myprog");
/// // Using a usage string (setting a similar argument to the one above)
/// let input = arg!(-i --input <FILE> "Provides an input file to the program");
/// ```
#[allow(missing_debug_implementations)]
#[derive(Default, Clone)]
pub struct Arg<'help> {
pub(crate) id: Id,
pub(crate) provider: ArgProvider,
pub(crate) name: &'help str,
pub(crate) help: Option<&'help str>,
pub(crate) long_help: Option<&'help str>,
pub(crate) action: Option<ArgAction>,
pub(crate) value_parser: Option<super::ValueParser>,
pub(crate) blacklist: Vec<Id>,
pub(crate) settings: ArgFlags,
pub(crate) overrides: Vec<Id>,
pub(crate) groups: Vec<Id>,
pub(crate) requires: Vec<(ArgPredicate<'help>, Id)>,
pub(crate) r_ifs: Vec<(Id, &'help str)>,
pub(crate) r_ifs_all: Vec<(Id, &'help str)>,
pub(crate) r_unless: Vec<Id>,
pub(crate) r_unless_all: Vec<Id>,
pub(crate) short: Option<char>,
pub(crate) long: Option<&'help str>,
pub(crate) aliases: Vec<(&'help str, bool)>, // (name, visible)
pub(crate) short_aliases: Vec<(char, bool)>, // (name, visible)
pub(crate) disp_ord: DisplayOrder,
pub(crate) possible_vals: Vec<PossibleValue<'help>>,
pub(crate) val_names: Vec<&'help str>,
pub(crate) num_vals: Option<usize>,
pub(crate) max_occurs: Option<usize>,
pub(crate) max_vals: Option<usize>,
pub(crate) min_vals: Option<usize>,
pub(crate) validator: Option<Arc<Mutex<Validator<'help>>>>,
pub(crate) validator_os: Option<Arc<Mutex<ValidatorOs<'help>>>>,
pub(crate) val_delim: Option<char>,
pub(crate) default_vals: Vec<&'help OsStr>,
pub(crate) default_vals_ifs: Vec<(Id, ArgPredicate<'help>, Option<&'help OsStr>)>,
pub(crate) default_missing_vals: Vec<&'help OsStr>,
#[cfg(feature = "env")]
pub(crate) env: Option<(&'help OsStr, Option<OsString>)>,
pub(crate) terminator: Option<&'help str>,
pub(crate) index: Option<usize>,
pub(crate) help_heading: Option<Option<&'help str>>,
pub(crate) value_hint: Option<ValueHint>,
}
/// # Basic API
impl<'help> Arg<'help> {
/// Create a new [`Arg`] with a unique name.
///
/// The name is used to check whether or not the argument was used at
/// runtime, get values, set relationships with other args, etc..
///
/// **NOTE:** In the case of arguments that take values (i.e. [`Arg::takes_value(true)`])
/// and positional arguments (i.e. those without a preceding `-` or `--`) the name will also
/// be displayed when the user prints the usage/help information of the program.
///
/// # Examples
///
/// ```rust
/// # use clap::{Command, Arg};
/// Arg::new("config")
/// # ;
/// ```
/// [`Arg::takes_value(true)`]: Arg::takes_value()
pub fn new<S: Into<&'help str>>(n: S) -> Self {
Arg::default().name(n)
}
/// Set the identifier used for referencing this argument in the clap API.
///
/// See [`Arg::new`] for more details.
#[must_use]
pub fn id<S: Into<&'help str>>(mut self, n: S) -> Self {
let name = n.into();
self.id = Id::from(&*name);
self.name = name;
self
}
/// Deprecated, replaced with [`Arg::id`]
#[deprecated(since = "3.1.0", note = "Replaced with `Arg::id`")]
pub fn name<S: Into<&'help str>>(self, n: S) -> Self {
self.id(n)
}
/// Sets the short version of the argument without the preceding `-`.
///
/// By default `V` and `h` are used by the auto-generated `version` and `help` arguments,
/// respectively. You may use the uppercase `V` or lowercase `h` for your own arguments, in
/// which case `clap` simply will not assign those to the auto-generated
/// `version` or `help` arguments.
///
/// # Examples
///
/// When calling `short`, use a single valid UTF-8 character which will allow using the
/// argument via a single hyphen (`-`) such as `-c`:
///
/// ```rust
/// # use clap::{Command, Arg};
/// let m = Command::new("prog")
/// .arg(Arg::new("config")
/// .short('c'))
/// .get_matches_from(vec![
/// "prog", "-c"
/// ]);
///
/// assert!(m.is_present("config"));
/// ```
#[inline]
#[must_use]
pub fn short(mut self, s: char) -> Self {
assert!(s != '-', "short option name cannot be `-`");
self.short = Some(s);
self
}
/// Sets the long version of the argument without the preceding `--`.
///
/// By default `version` and `help` are used by the auto-generated `version` and `help`
/// arguments, respectively. You may use the word `version` or `help` for the long form of your
/// own arguments, in which case `clap` simply will not assign those to the auto-generated
/// `version` or `help` arguments.
///
/// **NOTE:** Any leading `-` characters will be stripped
///
/// # Examples
///
/// To set `long` use a word containing valid UTF-8. If you supply a double leading
/// `--` such as `--config` they will be stripped. Hyphens in the middle of the word, however,
/// will *not* be stripped (i.e. `config-file` is allowed).
///
/// Setting `long` allows using the argument via a double hyphen (`--`) such as `--config`
///
/// ```rust
/// # use clap::{Command, Arg};
/// let m = Command::new("prog")
/// .arg(Arg::new("cfg")
/// .long("config"))
/// .get_matches_from(vec![
/// "prog", "--config"
/// ]);
///
/// assert!(m.is_present("cfg"));
/// ```
#[inline]
#[must_use]
pub fn long(mut self, l: &'help str) -> Self {
#[cfg(feature = "unstable-v4")]
{
self.long = Some(l);
}
#[cfg(not(feature = "unstable-v4"))]
{
self.long = Some(l.trim_start_matches(|c| c == '-'));
}
self
}
/// Add an alias, which functions as a hidden long flag.
///
/// This is more efficient, and easier than creating multiple hidden arguments as one only
/// needs to check for the existence of this command, and not all variants.
///
/// # Examples
///
/// ```rust
/// # use clap::{Command, Arg};
/// let m = Command::new("prog")
/// .arg(Arg::new("test")
/// .long("test")
/// .alias("alias")
/// .takes_value(true))
/// .get_matches_from(vec![
/// "prog", "--alias", "cool"
/// ]);
/// assert!(m.is_present("test"));
/// assert_eq!(m.value_of("test"), Some("cool"));
/// ```
#[must_use]
pub fn alias<S: Into<&'help str>>(mut self, name: S) -> Self {
self.aliases.push((name.into(), false));
self
}
/// Add an alias, which functions as a hidden short flag.
///
/// This is more efficient, and easier than creating multiple hidden arguments as one only
/// needs to check for the existence of this command, and not all variants.
///
/// # Examples
///
/// ```rust
/// # use clap::{Command, Arg};
/// let m = Command::new("prog")
/// .arg(Arg::new("test")
/// .short('t')
/// .short_alias('e')
/// .takes_value(true))
/// .get_matches_from(vec![
/// "prog", "-e", "cool"
/// ]);
/// assert!(m.is_present("test"));
/// assert_eq!(m.value_of("test"), Some("cool"));
/// ```
#[must_use]
pub fn short_alias(mut self, name: char) -> Self {
assert!(name != '-', "short alias name cannot be `-`");
self.short_aliases.push((name, false));
self
}
/// Add aliases, which function as hidden long flags.
///
/// This is more efficient, and easier than creating multiple hidden subcommands as one only
/// needs to check for the existence of this command, and not all variants.
///
/// # Examples
///
/// ```rust
/// # use clap::{Command, Arg};
/// let m = Command::new("prog")
/// .arg(Arg::new("test")
/// .long("test")
/// .aliases(&["do-stuff", "do-tests", "tests"])
/// .help("the file to add")
/// .required(false))
/// .get_matches_from(vec![
/// "prog", "--do-tests"
/// ]);
/// assert!(m.is_present("test"));
/// ```
#[must_use]
pub fn aliases(mut self, names: &[&'help str]) -> Self {
self.aliases.extend(names.iter().map(|&x| (x, false)));
self
}
/// Add aliases, which functions as a hidden short flag.
///
/// This is more efficient, and easier than creating multiple hidden subcommands as one only
/// needs to check for the existence of this command, and not all variants.
///
/// # Examples
///
/// ```rust
/// # use clap::{Command, Arg};
/// let m = Command::new("prog")
/// .arg(Arg::new("test")
/// .short('t')
/// .short_aliases(&['e', 's'])
/// .help("the file to add")
/// .required(false))
/// .get_matches_from(vec![
/// "prog", "-s"
/// ]);
/// assert!(m.is_present("test"));
/// ```
#[must_use]
pub fn short_aliases(mut self, names: &[char]) -> Self {
for s in names {
assert!(s != &'-', "short alias name cannot be `-`");
self.short_aliases.push((*s, false));
}
self
}
/// Add an alias, which functions as a visible long flag.
///
/// Like [`Arg::alias`], except that they are visible inside the help message.
///
/// # Examples
///
/// ```rust
/// # use clap::{Command, Arg};
/// let m = Command::new("prog")
/// .arg(Arg::new("test")
/// .visible_alias("something-awesome")
/// .long("test")
/// .takes_value(true))
/// .get_matches_from(vec![
/// "prog", "--something-awesome", "coffee"
/// ]);
/// assert!(m.is_present("test"));
/// assert_eq!(m.value_of("test"), Some("coffee"));
/// ```
/// [`Command::alias`]: Arg::alias()
#[must_use]
pub fn visible_alias<S: Into<&'help str>>(mut self, name: S) -> Self {
self.aliases.push((name.into(), true));
self
}
/// Add an alias, which functions as a visible short flag.
///
/// Like [`Arg::short_alias`], except that they are visible inside the help message.
///
/// # Examples
///
/// ```rust
/// # use clap::{Command, Arg};
/// let m = Command::new("prog")
/// .arg(Arg::new("test")
/// .long("test")
/// .visible_short_alias('t')
/// .takes_value(true))
/// .get_matches_from(vec![
/// "prog", "-t", "coffee"
/// ]);
/// assert!(m.is_present("test"));
/// assert_eq!(m.value_of("test"), Some("coffee"));
/// ```
#[must_use]
pub fn visible_short_alias(mut self, name: char) -> Self {
assert!(name != '-', "short alias name cannot be `-`");
self.short_aliases.push((name, true));
self
}
/// Add aliases, which function as visible long flags.
///
/// Like [`Arg::aliases`], except that they are visible inside the help message.
///
/// # Examples
///
/// ```rust
/// # use clap::{Command, Arg};
/// let m = Command::new("prog")
/// .arg(Arg::new("test")
/// .long("test")
/// .visible_aliases(&["something", "awesome", "cool"]))
/// .get_matches_from(vec![
/// "prog", "--awesome"
/// ]);
/// assert!(m.is_present("test"));
/// ```
/// [`Command::aliases`]: Arg::aliases()
#[must_use]
pub fn visible_aliases(mut self, names: &[&'help str]) -> Self {
self.aliases.extend(names.iter().map(|n| (*n, true)));
self
}
/// Add aliases, which function as visible short flags.
///
/// Like [`Arg::short_aliases`], except that they are visible inside the help message.
///
/// # Examples
///
/// ```rust
/// # use clap::{Command, Arg};
/// let m = Command::new("prog")
/// .arg(Arg::new("test")
/// .long("test")
/// .visible_short_aliases(&['t', 'e']))
/// .get_matches_from(vec![
/// "prog", "-t"
/// ]);
/// assert!(m.is_present("test"));
/// ```
#[must_use]
pub fn visible_short_aliases(mut self, names: &[char]) -> Self {
for n in names {
assert!(n != &'-', "short alias name cannot be `-`");
self.short_aliases.push((*n, true));
}
self
}
/// Specifies the index of a positional argument **starting at** 1.
///
/// **NOTE:** The index refers to position according to **other positional argument**. It does
/// not define position in the argument list as a whole.
///
/// **NOTE:** You can optionally leave off the `index` method, and the index will be
/// assigned in order of evaluation. Utilizing the `index` method allows for setting
/// indexes out of order
///
/// **NOTE:** This is only meant to be used for positional arguments and shouldn't to be used
/// with [`Arg::short`] or [`Arg::long`].
///
/// **NOTE:** When utilized with [`Arg::multiple_values(true)`], only the **last** positional argument
/// may be defined as multiple (i.e. with the highest index)
///
/// # Panics
///
/// [`Command`] will [`panic!`] if indexes are skipped (such as defining `index(1)` and `index(3)`
/// but not `index(2)`, or a positional argument is defined as multiple and is not the highest
/// index
///
/// # Examples
///
/// ```rust
/// # use clap::{Command, Arg};
/// Arg::new("config")
/// .index(1)
/// # ;
/// ```
///
/// ```rust
/// # use clap::{Command, Arg};
/// let m = Command::new("prog")
/// .arg(Arg::new("mode")
/// .index(1))
/// .arg(Arg::new("debug")
/// .long("debug"))
/// .get_matches_from(vec![
/// "prog", "--debug", "fast"
/// ]);
///
/// assert!(m.is_present("mode"));
/// assert_eq!(m.value_of("mode"), Some("fast")); // notice index(1) means "first positional"
/// // *not* first argument
/// ```
/// [`Arg::short`]: Arg::short()
/// [`Arg::long`]: Arg::long()
/// [`Arg::multiple_values(true)`]: Arg::multiple_values()
/// [`panic!`]: https://doc.rust-lang.org/std/macro.panic!.html
/// [`Command`]: crate::Command
#[inline]
#[must_use]
pub fn index(mut self, idx: usize) -> Self {
self.index = Some(idx);
self
}
/// This arg is the last, or final, positional argument (i.e. has the highest
/// index) and is *only* able to be accessed via the `--` syntax (i.e. `$ prog args --
/// last_arg`).
///
/// Even, if no other arguments are left to parse, if the user omits the `--` syntax
/// they will receive an [`UnknownArgument`] error. Setting an argument to `.last(true)` also
/// allows one to access this arg early using the `--` syntax. Accessing an arg early, even with
/// the `--` syntax is otherwise not possible.
///
/// **NOTE:** This will change the usage string to look like `$ prog [OPTIONS] [-- <ARG>]` if
/// `ARG` is marked as `.last(true)`.
///
/// **NOTE:** This setting will imply [`crate::Command::dont_collapse_args_in_usage`] because failing
/// to set this can make the usage string very confusing.
///
/// **NOTE**: This setting only applies to positional arguments, and has no effect on OPTIONS
///
/// **NOTE:** Setting this requires [`Arg::takes_value`]
///
/// **CAUTION:** Using this setting *and* having child subcommands is not
/// recommended with the exception of *also* using
/// [`crate::Command::args_conflicts_with_subcommands`]
/// (or [`crate::Command::subcommand_negates_reqs`] if the argument marked `Last` is also
/// marked [`Arg::required`])
///
/// # Examples
///
/// ```rust
/// # use clap::Arg;
/// Arg::new("args")
/// .takes_value(true)
/// .last(true)
/// # ;
/// ```
///
/// Setting `last` ensures the arg has the highest [index] of all positional args
/// and requires that the `--` syntax be used to access it early.
///
/// ```rust
/// # use clap::{Command, Arg};
/// let res = Command::new("prog")
/// .arg(Arg::new("first"))
/// .arg(Arg::new("second"))
/// .arg(Arg::new("third")
/// .takes_value(true)
/// .last(true))
/// .try_get_matches_from(vec![
/// "prog", "one", "--", "three"
/// ]);
///
/// assert!(res.is_ok());
/// let m = res.unwrap();
/// assert_eq!(m.value_of("third"), Some("three"));
/// assert!(m.value_of("second").is_none());
/// ```
///
/// Even if the positional argument marked `Last` is the only argument left to parse,
/// failing to use the `--` syntax results in an error.
///
/// ```rust
/// # use clap::{Command, Arg, ErrorKind};
/// let res = Command::new("prog")
/// .arg(Arg::new("first"))
/// .arg(Arg::new("second"))
/// .arg(Arg::new("third")
/// .takes_value(true)
/// .last(true))
/// .try_get_matches_from(vec![
/// "prog", "one", "two", "three"
/// ]);
///
/// assert!(res.is_err());
/// assert_eq!(res.unwrap_err().kind(), ErrorKind::UnknownArgument);
/// ```
/// [index]: Arg::index()
/// [`UnknownArgument`]: crate::ErrorKind::UnknownArgument
#[inline]
#[must_use]
pub fn last(self, yes: bool) -> Self {
if yes {
self.setting(ArgSettings::Last)
} else {
self.unset_setting(ArgSettings::Last)
}
}
/// Specifies that the argument must be present.
///
/// Required by default means it is required, when no other conflicting rules or overrides have
/// been evaluated. Conflicting rules take precedence over being required.
///
/// **Pro tip:** Flags (i.e. not positional, or arguments that take values) shouldn't be
/// required by default. This is because if a flag were to be required, it should simply be
/// implied. No additional information is required from user. Flags by their very nature are
/// simply boolean on/off switches. The only time a user *should* be required to use a flag
/// is if the operation is destructive in nature, and the user is essentially proving to you,
/// "Yes, I know what I'm doing."
///
/// # Examples
///
/// ```rust
/// # use clap::Arg;
/// Arg::new("config")
/// .required(true)
/// # ;
/// ```
///
/// Setting required requires that the argument be used at runtime.
///
/// ```rust
/// # use clap::{Command, Arg};
/// let res = Command::new("prog")
/// .arg(Arg::new("cfg")
/// .required(true)
/// .takes_value(true)
/// .long("config"))
/// .try_get_matches_from(vec![
/// "prog", "--config", "file.conf",
/// ]);
///
/// assert!(res.is_ok());
/// ```
///
/// Setting required and then *not* supplying that argument at runtime is an error.
///
/// ```rust
/// # use clap::{Command, Arg, ErrorKind};
/// let res = Command::new("prog")
/// .arg(Arg::new("cfg")
/// .required(true)
/// .takes_value(true)
/// .long("config"))
/// .try_get_matches_from(vec![
/// "prog"
/// ]);
///
/// assert!(res.is_err());
/// assert_eq!(res.unwrap_err().kind(), ErrorKind::MissingRequiredArgument);
/// ```
#[inline]
#[must_use]
pub fn required(self, yes: bool) -> Self {
if yes {
self.setting(ArgSettings::Required)
} else {
self.unset_setting(ArgSettings::Required)
}
}
/// Sets an argument that is required when this one is present
///
/// i.e. when using this argument, the following argument *must* be present.
///
/// **NOTE:** [Conflicting] rules and [override] rules take precedence over being required
///
/// # Examples
///
/// ```rust
/// # use clap::Arg;
/// Arg::new("config")
/// .requires("input")
/// # ;
/// ```
///
/// Setting [`Arg::requires(name)`] requires that the argument be used at runtime if the
/// defining argument is used. If the defining argument isn't used, the other argument isn't
/// required
///
/// ```rust
/// # use clap::{Command, Arg};
/// let res = Command::new("prog")
/// .arg(Arg::new("cfg")
/// .takes_value(true)
/// .requires("input")
/// .long("config"))
/// .arg(Arg::new("input"))
/// .try_get_matches_from(vec![
/// "prog"
/// ]);
///
/// assert!(res.is_ok()); // We didn't use cfg, so input wasn't required
/// ```
///
/// Setting [`Arg::requires(name)`] and *not* supplying that argument is an error.
///
/// ```rust
/// # use clap::{Command, Arg, ErrorKind};
/// let res = Command::new("prog")
/// .arg(Arg::new("cfg")
/// .takes_value(true)
/// .requires("input")
/// .long("config"))
/// .arg(Arg::new("input"))
/// .try_get_matches_from(vec![
/// "prog", "--config", "file.conf"
/// ]);
///
/// assert!(res.is_err());
/// assert_eq!(res.unwrap_err().kind(), ErrorKind::MissingRequiredArgument);
/// ```
/// [`Arg::requires(name)`]: Arg::requires()
/// [Conflicting]: Arg::conflicts_with()
/// [override]: Arg::overrides_with()
#[must_use]
pub fn requires<T: Key>(mut self, arg_id: T) -> Self {
self.requires.push((ArgPredicate::IsPresent, arg_id.into()));
self
}
/// This argument must be passed alone; it conflicts with all other arguments.
///
/// # Examples
///
/// ```rust
/// # use clap::Arg;
/// Arg::new("config")
/// .exclusive(true)
/// # ;
/// ```
///
/// Setting an exclusive argument and having any other arguments present at runtime
/// is an error.
///
/// ```rust
/// # use clap::{Command, Arg, ErrorKind};
/// let res = Command::new("prog")
/// .arg(Arg::new("exclusive")
/// .takes_value(true)
/// .exclusive(true)
/// .long("exclusive"))
/// .arg(Arg::new("debug")
/// .long("debug"))
/// .arg(Arg::new("input"))
/// .try_get_matches_from(vec![
/// "prog", "--exclusive", "file.conf", "file.txt"
/// ]);
///
/// assert!(res.is_err());
/// assert_eq!(res.unwrap_err().kind(), ErrorKind::ArgumentConflict);
/// ```
#[inline]
#[must_use]
pub fn exclusive(self, yes: bool) -> Self {
if yes {
self.setting(ArgSettings::Exclusive)
} else {
self.unset_setting(ArgSettings::Exclusive)
}
}
/// Specifies that an argument can be matched to all child [`Subcommand`]s.
///
/// **NOTE:** Global arguments *only* propagate down, **not** up (to parent commands), however
/// their values once a user uses them will be propagated back up to parents. In effect, this
/// means one should *define* all global arguments at the top level, however it doesn't matter
/// where the user *uses* the global argument.
///
/// # Examples
///
/// Assume an application with two subcommands, and you'd like to define a
/// `--verbose` flag that can be called on any of the subcommands and parent, but you don't
/// want to clutter the source with three duplicate [`Arg`] definitions.
///
/// ```rust
/// # use clap::{Command, Arg};
/// let m = Command::new("prog")
/// .arg(Arg::new("verb")
/// .long("verbose")
/// .short('v')
/// .global(true))
/// .subcommand(Command::new("test"))
/// .subcommand(Command::new("do-stuff"))
/// .get_matches_from(vec![
/// "prog", "do-stuff", "--verbose"
/// ]);
///
/// assert_eq!(m.subcommand_name(), Some("do-stuff"));
/// let sub_m = m.subcommand_matches("do-stuff").unwrap();
/// assert!(sub_m.is_present("verb"));
/// ```
///
/// [`Subcommand`]: crate::Subcommand
/// [`ArgMatches::is_present("flag")`]: ArgMatches::is_present()
#[inline]
#[must_use]
pub fn global(self, yes: bool) -> Self {
if yes {
self.setting(ArgSettings::Global)
} else {
self.unset_setting(ArgSettings::Global)
}
}
/// Deprecated, replaced with [`Arg::action`] ([Issue #3772](https://github.com/clap-rs/clap/issues/3772))
#[inline]
#[must_use]
#[deprecated(since = "3.2.0", note = "Replaced with `Arg::action` (Issue #3772)")]
pub fn multiple_occurrences(self, yes: bool) -> Self {
if yes {
self.setting(ArgSettings::MultipleOccurrences)
} else {
self.unset_setting(ArgSettings::MultipleOccurrences)
}
}
/// Deprecated, for flags this is replaced with `action(ArgAction::Count).value_parser(value_parser!(u64).range(..max))`
#[inline]
#[must_use]
#[deprecated(
since = "3.2.0",
note = "For flags, replaced with `action(ArgAction::Count).value_parser(value_parser!(u64).range(..max))`"
)]
pub fn max_occurrences(mut self, qty: usize) -> Self {
self.max_occurs = Some(qty);
if qty > 1 {
self.multiple_occurrences(true)
} else {
self
}
}
/// Check if the [`ArgSettings`] variant is currently set on the argument.
///
/// [`ArgSettings`]: crate::ArgSettings
#[inline]
pub fn is_set(&self, s: ArgSettings) -> bool {
self.settings.is_set(s)
}
/// Apply a setting to the argument.
///
/// See [`ArgSettings`] for a full list of possibilities and examples.
///
/// # Examples
///
/// ```no_run
/// # use clap::{Arg, ArgSettings};
/// Arg::new("config")
/// .setting(ArgSettings::Required)
/// .setting(ArgSettings::TakesValue)
/// # ;
/// ```
///
/// ```no_run
/// # use clap::{Arg, ArgSettings};
/// Arg::new("config")
/// .setting(ArgSettings::Required | ArgSettings::TakesValue)
/// # ;
/// ```
#[inline]
#[must_use]
pub fn setting<F>(mut self, setting: F) -> Self
where
F: Into<ArgFlags>,
{
self.settings.insert(setting.into());
self
}
/// Remove a setting from the argument.
///
/// See [`ArgSettings`] for a full list of possibilities and examples.
///
/// # Examples
///
/// ```no_run
/// # use clap::{Arg, ArgSettings};
/// Arg::new("config")
/// .unset_setting(ArgSettings::Required)
/// .unset_setting(ArgSettings::TakesValue)
/// # ;
/// ```
///
/// ```no_run
/// # use clap::{Arg, ArgSettings};
/// Arg::new("config")
/// .unset_setting(ArgSettings::Required | ArgSettings::TakesValue)
/// # ;
/// ```
#[inline]
#[must_use]
pub fn unset_setting<F>(mut self, setting: F) -> Self
where
F: Into<ArgFlags>,
{
self.settings.remove(setting.into());
self
}
}
/// # Value Handling
impl<'help> Arg<'help> {
/// Specifies that the argument takes a value at run time.
///
/// **NOTE:** values for arguments may be specified in any of the following methods
///
/// - Using a space such as `-o value` or `--option value`
/// - Using an equals and no space such as `-o=value` or `--option=value`
/// - Use a short and no space such as `-ovalue`
///
/// **NOTE:** By default, args which allow [multiple values] are delimited by commas, meaning
/// `--option=val1,val2,val3` is three values for the `--option` argument. If you wish to
/// change the delimiter to another character you can use [`Arg::value_delimiter(char)`],
/// alternatively you can turn delimiting values **OFF** by using
/// [`Arg::use_value_delimiter(false)`][Arg::use_value_delimiter]
///
/// # Examples
///
/// ```rust
/// # use clap::{Command, Arg};
/// let m = Command::new("prog")
/// .arg(Arg::new("mode")
/// .long("mode")
/// .takes_value(true))
/// .get_matches_from(vec![
/// "prog", "--mode", "fast"
/// ]);
///
/// assert!(m.is_present("mode"));
/// assert_eq!(m.value_of("mode"), Some("fast"));
/// ```
/// [`Arg::value_delimiter(char)`]: Arg::value_delimiter()
/// [multiple values]: Arg::multiple_values
#[inline]
#[must_use]
pub fn takes_value(self, yes: bool) -> Self {
if yes {
self.setting(ArgSettings::TakesValue)
} else {
self.unset_setting(ArgSettings::TakesValue)
}
}
/// Specify the behavior when parsing an argument
///
/// # Examples
///
/// ```rust
/// # use clap::Command;
/// # use clap::Arg;
/// let cmd = Command::new("mycmd")
/// .arg(
/// Arg::new("flag")
/// .long("flag")
/// .action(clap::ArgAction::Set)
/// );
///
/// let matches = cmd.try_get_matches_from(["mycmd", "--flag", "value"]).unwrap();
/// assert!(matches.is_present("flag"));
/// assert_eq!(matches.occurrences_of("flag"), 0);
/// assert_eq!(
/// matches.get_many::<String>("flag").unwrap_or_default().map(|v| v.as_str()).collect::<Vec<_>>(),
/// vec!["value"]
/// );
/// ```
#[inline]
#[must_use]
pub fn action(mut self, action: ArgAction) -> Self {
self.action = Some(action);
self
}
/// Specify the type of the argument.
///
/// This allows parsing and validating a value before storing it into
/// [`ArgMatches`][crate::ArgMatches].
///
/// See also
/// - [`value_parser!`][crate::value_parser!] for auto-selecting a value parser for a given type
/// - [`BoolishValueParser`][crate::builder::BoolishValueParser], and [`FalseyValueParser`][crate::builder::FalseyValueParser] for alternative `bool` implementations
/// - [`NonEmptyStringValueParser`][crate::builder::NonEmptyStringValueParser] for basic validation for strings
/// - [`RangedI64ValueParser`][crate::builder::RangedI64ValueParser] and [`RangedU64ValueParser`][crate::builder::RangedU64ValueParser] for numeric ranges
/// - [`EnumValueParser`][crate::builder::EnumValueParser] and [`PossibleValuesParser`][crate::builder::PossibleValuesParser] for static enumerated values
/// - or any other [`TypedValueParser`][crate::builder::TypedValueParser] implementation
///
/// ```rust
/// let mut cmd = clap::Command::new("raw")
/// .arg(
/// clap::Arg::new("color")
/// .long("color")
/// .value_parser(["always", "auto", "never"])
/// .default_value("auto")
/// )
/// .arg(
/// clap::Arg::new("hostname")
/// .long("hostname")
/// .value_parser(clap::builder::NonEmptyStringValueParser::new())
/// .takes_value(true)
/// .required(true)
/// )
/// .arg(
/// clap::Arg::new("port")
/// .long("port")
/// .value_parser(clap::value_parser!(u16).range(3000..))
/// .takes_value(true)
/// .required(true)
/// );
///
/// let m = cmd.try_get_matches_from_mut(
/// ["cmd", "--hostname", "rust-lang.org", "--port", "3001"]
/// ).unwrap();
///
/// let color: &String = m.get_one("color")
/// .expect("default");
/// assert_eq!(color, "auto");
///
/// let hostname: &String = m.get_one("hostname")
/// .expect("required");
/// assert_eq!(hostname, "rust-lang.org");
///
/// let port: u16 = *m.get_one("port")
/// .expect("required");
/// assert_eq!(port, 3001);
/// ```
pub fn value_parser(mut self, parser: impl Into<super::ValueParser>) -> Self {