(index<- ) ./libfmt_macros/lib.rs
git branch: * master 5200215 auto merge of #14035 : alexcrichton/rust/experimental, r=huonw
modified: Fri May 9 13:02:28 2014
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
4 //
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
10
11 //! Macro support for format strings
12 //!
13 //! These structures are used when parsing format strings for the compiler.
14 //! Parsing does not happen at runtime: structures of `std::fmt::rt` are
15 //! generated instead.
16
17 #![crate_id = "fmt_macros#0.11-pre"]
18 #![license = "MIT/ASL2"]
19 #![crate_type = "rlib"]
20 #![crate_type = "dylib"]
21 #![feature(macro_rules, globs)]
22 #![experimental]
23
24 use std::char;
25 use std::str;
26
27 /// A piece is a portion of the format string which represents the next part
28 /// to emit. These are emitted as a stream by the `Parser` class.
29 #[deriving(Eq)]
30 pub enum Piece<'a> {
31 /// A literal string which should directly be emitted
32 String(&'a str),
33 /// A back-reference to whatever the current argument is. This is used
34 /// inside of a method call to refer back to the original argument.
35 CurrentArgument,
36 /// This describes that formatting should process the next argument (as
37 /// specified inside) for emission.
38 Argument(Argument<'a>),
39 }
40
41 /// Representation of an argument specification.
42 #[deriving(Eq)]
43 pub struct Argument<'a> {
44 /// Where to find this argument
45 pub position: Position<'a>,
46 /// How to format the argument
47 pub format: FormatSpec<'a>,
48 /// If not `None`, what method to invoke on the argument
49 pub method: Option<Box<Method<'a>>>
50 }
51
52 /// Specification for the formatting of an argument in the format string.
53 #[deriving(Eq)]
54 pub struct FormatSpec<'a> {
55 /// Optionally specified character to fill alignment with
56 pub fill: Option<char>,
57 /// Optionally specified alignment
58 pub align: Alignment,
59 /// Packed version of various flags provided
60 pub flags: uint,
61 /// The integer precision to use
62 pub precision: Count<'a>,
63 /// The string width requested for the resulting format
64 pub width: Count<'a>,
65 /// The descriptor string representing the name of the format desired for
66 /// this argument, this can be empty or any number of characters, although
67 /// it is required to be one word.
68 pub ty: &'a str
69 }
70
71 /// Enum describing where an argument for a format can be located.
72 #[deriving(Eq)]
73 pub enum Position<'a> {
74 /// The argument will be in the next position. This is the default.
75 ArgumentNext,
76 /// The argument is located at a specific index.
77 ArgumentIs(uint),
78 /// The argument has a name.
79 ArgumentNamed(&'a str),
80 }
81
82 /// Enum of alignments which are supported.
83 #[deriving(Eq)]
84 pub enum Alignment {
85 /// The value will be aligned to the left.
86 AlignLeft,
87 /// The value will be aligned to the right.
88 AlignRight,
89 /// The value will take on a default alignment.
90 AlignUnknown,
91 }
92
93 /// Various flags which can be applied to format strings. The meaning of these
94 /// flags is defined by the formatters themselves.
95 #[deriving(Eq)]
96 pub enum Flag {
97 /// A `+` will be used to denote positive numbers.
98 FlagSignPlus,
99 /// A `-` will be used to denote negative numbers. This is the default.
100 FlagSignMinus,
101 /// An alternate form will be used for the value. In the case of numbers,
102 /// this means that the number will be prefixed with the supplied string.
103 FlagAlternate,
104 /// For numbers, this means that the number will be padded with zeroes,
105 /// and the sign (`+` or `-`) will precede them.
106 FlagSignAwareZeroPad,
107 }
108
109 /// A count is used for the precision and width parameters of an integer, and
110 /// can reference either an argument or a literal integer.
111 #[deriving(Eq)]
112 pub enum Count<'a> {
113 /// The count is specified explicitly.
114 CountIs(uint),
115 /// The count is specified by the argument with the given name.
116 CountIsName(&'a str),
117 /// The count is specified by the argument at the given index.
118 CountIsParam(uint),
119 /// The count is specified by the next parameter.
120 CountIsNextParam,
121 /// The count is implied and cannot be explicitly specified.
122 CountImplied,
123 }
124
125 /// Enum describing all of the possible methods which the formatting language
126 /// currently supports.
127 #[deriving(Eq)]
128 pub enum Method<'a> {
129 /// A plural method selects on an integer over a list of either integer or
130 /// keyword-defined clauses. The meaning of the keywords is defined by the
131 /// current locale.
132 ///
133 /// An offset is optionally present at the beginning which is used to
134 /// match against keywords, but it is not matched against the literal
135 /// integers.
136 ///
137 /// The final element of this enum is the default "other" case which is
138 /// always required to be specified.
139 Plural(Option<uint>, Vec<PluralArm<'a>>, Vec<Piece<'a>>),
140
141 /// A select method selects over a string. Each arm is a different string
142 /// which can be selected for.
143 ///
144 /// As with `Plural`, a default "other" case is required as well.
145 Select(Vec<SelectArm<'a>>, Vec<Piece<'a>>),
146 }
147
148 /// A selector for what pluralization a plural method should take
149 #[deriving(Eq, TotalEq, Hash)]
150 pub enum PluralSelector {
151 /// One of the plural keywords should be used
152 Keyword(PluralKeyword),
153 /// A literal pluralization should be used
154 Literal(uint),
155 }
156
157 /// Structure representing one "arm" of the `plural` function.
158 #[deriving(Eq)]
159 pub struct PluralArm<'a> {
160 /// A selector can either be specified by a keyword or with an integer
161 /// literal.
162 pub selector: PluralSelector,
163 /// Array of pieces which are the format of this arm
164 pub result: Vec<Piece<'a>>,
165 }
166
167 /// Enum of the 5 CLDR plural keywords. There is one more, "other", but that
168 /// is specially placed in the `Plural` variant of `Method`.
169 ///
170 /// http://www.icu-project.org/apiref/icu4c/classicu_1_1PluralRules.html
171 #[deriving(Eq, TotalEq, Hash, Show)]
172 #[allow(missing_doc)]
173 pub enum PluralKeyword {
174 /// The plural form for zero objects.
175 Zero,
176 /// The plural form for one object.
177 One,
178 /// The plural form for two objects.
179 Two,
180 /// The plural form for few objects.
181 Few,
182 /// The plural form for many objects.
183 Many,
184 }
185
186 /// Structure representing one "arm" of the `select` function.
187 #[deriving(Eq)]
188 pub struct SelectArm<'a> {
189 /// String selector which guards this arm
190 pub selector: &'a str,
191 /// Array of pieces which are the format of this arm
192 pub result: Vec<Piece<'a>>,
193 }
194
195 /// The parser structure for interpreting the input format string. This is
196 /// modelled as an iterator over `Piece` structures to form a stream of tokens
197 /// being output.
198 ///
199 /// This is a recursive-descent parser for the sake of simplicity, and if
200 /// necessary there's probably lots of room for improvement performance-wise.
201 pub struct Parser<'a> {
202 input: &'a str,
203 cur: str::CharOffsets<'a>,
204 depth: uint,
205 /// Error messages accumulated during parsing
206 pub errors: Vec<~str>,
207 }
208
209 impl<'a> Iterator<Piece<'a>> for Parser<'a> {
210 fn next(&mut self) -> Option<Piece<'a>> {
211 match self.cur.clone().next() {
212 Some((_, '#')) => { self.cur.next(); Some(CurrentArgument) }
213 Some((_, '{')) => {
214 self.cur.next();
215 let ret = Some(Argument(self.argument()));
216 self.must_consume('}');
217 ret
218 }
219 Some((pos, '\\')) => {
220 self.cur.next();
221 self.escape(); // ensure it's a valid escape sequence
222 Some(String(self.string(pos + 1))) // skip the '\' character
223 }
224 Some((_, '}')) if self.depth == 0 => {
225 self.cur.next();
226 self.err("unmatched `}` found");
227 None
228 }
229 Some((_, '}')) | None => { None }
230 Some((pos, _)) => {
231 Some(String(self.string(pos)))
232 }
233 }
234 }
235 }
236
237 impl<'a> Parser<'a> {
238 /// Creates a new parser for the given format string
239 pub fn new<'a>(s: &'a str) -> Parser<'a> {
240 Parser {
241 input: s,
242 cur: s.char_indices(),
243 depth: 0,
244 errors: vec!(),
245 }
246 }
247
248 /// Notifies of an error. The message doesn't actually need to be of type
249 /// ~str, but I think it does when this eventually uses conditions so it
250 /// might as well start using it now.
251 fn err(&mut self, msg: &str) {
252 self.errors.push(msg.to_owned());
253 }
254
255 /// Optionally consumes the specified character. If the character is not at
256 /// the current position, then the current iterator isn't moved and false is
257 /// returned, otherwise the character is consumed and true is returned.
258 fn consume(&mut self, c: char) -> bool {
259 match self.cur.clone().next() {
260 Some((_, maybe)) if c == maybe => {
261 self.cur.next();
262 true
263 }
264 Some(..) | None => false,
265 }
266 }
267
268 /// Forces consumption of the specified character. If the character is not
269 /// found, an error is emitted.
270 fn must_consume(&mut self, c: char) {
271 self.ws();
272 match self.cur.clone().next() {
273 Some((_, maybe)) if c == maybe => {
274 self.cur.next();
275 }
276 Some((_, other)) => {
277 self.err(
278 format!("expected `{}` but found `{}`", c, other));
279 }
280 None => {
281 self.err(
282 format!("expected `{}` but string was terminated", c));
283 }
284 }
285 }
286
287 /// Attempts to consume any amount of whitespace followed by a character
288 fn wsconsume(&mut self, c: char) -> bool {
289 self.ws(); self.consume(c)
290 }
291
292 /// Consumes all whitespace characters until the first non-whitespace
293 /// character
294 fn ws(&mut self) {
295 loop {
296 match self.cur.clone().next() {
297 Some((_, c)) if char::is_whitespace(c) => { self.cur.next(); }
298 Some(..) | None => { return }
299 }
300 }
301 }
302
303 /// Consumes an escape sequence, failing if there is not a valid character
304 /// to be escaped.
305 fn escape(&mut self) -> char {
306 match self.cur.next() {
307 Some((_, c @ '#')) | Some((_, c @ '{')) |
308 Some((_, c @ '\\')) | Some((_, c @ '}')) => { c }
309 Some((_, c)) => {
310 self.err(format!("invalid escape character `{}`", c));
311 c
312 }
313 None => {
314 self.err("expected an escape sequence, but format string was \
315 terminated");
316 ' '
317 }
318 }
319 }
320
321 /// Parses all of a string which is to be considered a "raw literal" in a
322 /// format string. This is everything outside of the braces.
323 fn string(&mut self, start: uint) -> &'a str {
324 loop {
325 // we may not consume the character, so clone the iterator
326 match self.cur.clone().next() {
327 Some((pos, '\\')) | Some((pos, '#')) |
328 Some((pos, '}')) | Some((pos, '{')) => {
329 return self.input.slice(start, pos);
330 }
331 Some(..) => { self.cur.next(); }
332 None => {
333 self.cur.next();
334 return self.input.slice(start, self.input.len());
335 }
336 }
337 }
338 }
339
340 /// Parses an Argument structure, or what's contained within braces inside
341 /// the format string
342 fn argument(&mut self) -> Argument<'a> {
343 Argument {
344 position: self.position(),
345 format: self.format(),
346 method: self.method(),
347 }
348 }
349
350 /// Parses a positional argument for a format. This could either be an
351 /// integer index of an argument, a named argument, or a blank string.
352 fn position(&mut self) -> Position<'a> {
353 match self.integer() {
354 Some(i) => { ArgumentIs(i) }
355 None => {
356 match self.cur.clone().next() {
357 Some((_, c)) if char::is_alphabetic(c) => {
358 ArgumentNamed(self.word())
359 }
360 _ => ArgumentNext
361 }
362 }
363 }
364 }
365
366 /// Parses a format specifier at the current position, returning all of the
367 /// relevant information in the FormatSpec struct.
368 fn format(&mut self) -> FormatSpec<'a> {
369 let mut spec = FormatSpec {
370 fill: None,
371 align: AlignUnknown,
372 flags: 0,
373 precision: CountImplied,
374 width: CountImplied,
375 ty: self.input.slice(0, 0),
376 };
377 if !self.consume(':') { return spec }
378
379 // fill character
380 match self.cur.clone().next() {
381 Some((_, c)) => {
382 match self.cur.clone().skip(1).next() {
383 Some((_, '>')) | Some((_, '<')) => {
384 spec.fill = Some(c);
385 self.cur.next();
386 }
387 Some(..) | None => {}
388 }
389 }
390 None => {}
391 }
392 // Alignment
393 if self.consume('<') {
394 spec.align = AlignLeft;
395 } else if self.consume('>') {
396 spec.align = AlignRight;
397 }
398 // Sign flags
399 if self.consume('+') {
400 spec.flags |= 1 << (FlagSignPlus as uint);
401 } else if self.consume('-') {
402 spec.flags |= 1 << (FlagSignMinus as uint);
403 }
404 // Alternate marker
405 if self.consume('#') {
406 spec.flags |= 1 << (FlagAlternate as uint);
407 }
408 // Width and precision
409 let mut havewidth = false;
410 if self.consume('0') {
411 // small ambiguity with '0$' as a format string. In theory this is a
412 // '0' flag and then an ill-formatted format string with just a '$'
413 // and no count, but this is better if we instead interpret this as
414 // no '0' flag and '0$' as the width instead.
415 if self.consume('$') {
416 spec.width = CountIsParam(0);
417 havewidth = true;
418 } else {
419 spec.flags |= 1 << (FlagSignAwareZeroPad as uint);
420 }
421 }
422 if !havewidth {
423 spec.width = self.count();
424 }
425 if self.consume('.') {
426 if self.consume('*') {
427 spec.precision = CountIsNextParam;
428 } else {
429 spec.precision = self.count();
430 }
431 }
432 // Finally the actual format specifier
433 if self.consume('?') {
434 spec.ty = "?";
435 } else {
436 spec.ty = self.word();
437 }
438 return spec;
439 }
440
441 /// Parses a method to be applied to the previously specified argument and
442 /// its format. The two current supported methods are 'plural' and 'select'
443 fn method(&mut self) -> Option<Box<Method<'a>>> {
444 if !self.wsconsume(',') {
445 return None;
446 }
447 self.ws();
448 match self.word() {
449 "select" => {
450 self.must_consume(',');
451 Some(self.select())
452 }
453 "plural" => {
454 self.must_consume(',');
455 Some(self.plural())
456 }
457 "" => {
458 self.err("expected method after comma");
459 return None;
460 }
461 method => {
462 self.err(format!("unknown method: `{}`", method));
463 return None;
464 }
465 }
466 }
467
468 /// Parses a 'select' statement (after the initial 'select' word)
469 fn select(&mut self) -> Box<Method<'a>> {
470 let mut other = None;
471 let mut arms = vec!();
472 // Consume arms one at a time
473 loop {
474 self.ws();
475 let selector = self.word();
476 if selector == "" {
477 self.err("cannot have an empty selector");
478 break
479 }
480 self.must_consume('{');
481 self.depth += 1;
482 let pieces = self.collect();
483 self.depth -= 1;
484 self.must_consume('}');
485 if selector == "other" {
486 if !other.is_none() {
487 self.err("multiple `other` statements in `select");
488 }
489 other = Some(pieces);
490 } else {
491 arms.push(SelectArm { selector: selector, result: pieces });
492 }
493 self.ws();
494 match self.cur.clone().next() {
495 Some((_, '}')) => { break }
496 Some(..) | None => {}
497 }
498 }
499 // The "other" selector must be present
500 let other = match other {
501 Some(arm) => { arm }
502 None => {
503 self.err("`select` statement must provide an `other` case");
504 vec!()
505 }
506 };
507 box Select(arms, other)
508 }
509
510 /// Parses a 'plural' statement (after the initial 'plural' word)
511 fn plural(&mut self) -> Box<Method<'a>> {
512 let mut offset = None;
513 let mut other = None;
514 let mut arms = vec!();
515
516 // First, attempt to parse the 'offset:' field. We know the set of
517 // selector words which can appear in plural arms, and the only ones
518 // which start with 'o' are "other" and "offset", hence look two
519 // characters deep to see if we can consume the word "offset"
520 self.ws();
521 let mut it = self.cur.clone();
522 match it.next() {
523 Some((_, 'o')) => {
524 match it.next() {
525 Some((_, 'f')) => {
526 let word = self.word();
527 if word != "offset" {
528 self.err(format!("expected `offset`, found `{}`",
529 word));
530 } else {
531 self.must_consume(':');
532 match self.integer() {
533 Some(i) => { offset = Some(i); }
534 None => {
535 self.err("offset must be an integer");
536 }
537 }
538 }
539 }
540 Some(..) | None => {}
541 }
542 }
543 Some(..) | None => {}
544 }
545
546 // Next, generate all the arms
547 loop {
548 let mut isother = false;
549 let selector = if self.wsconsume('=') {
550 match self.integer() {
551 Some(i) => Literal(i),
552 None => {
553 self.err("plural `=` selectors must be followed by an \
554 integer");
555 Literal(0)
556 }
557 }
558 } else {
559 let word = self.word();
560 match word {
561 "other" => { isother = true; Keyword(Zero) }
562 "zero" => Keyword(Zero),
563 "one" => Keyword(One),
564 "two" => Keyword(Two),
565 "few" => Keyword(Few),
566 "many" => Keyword(Many),
567 word => {
568 self.err(format!("unexpected plural selector `{}`",
569 word));
570 if word == "" {
571 break
572 } else {
573 Keyword(Zero)
574 }
575 }
576 }
577 };
578 self.must_consume('{');
579 self.depth += 1;
580 let pieces = self.collect();
581 self.depth -= 1;
582 self.must_consume('}');
583 if isother {
584 if !other.is_none() {
585 self.err("multiple `other` statements in `select");
586 }
587 other = Some(pieces);
588 } else {
589 arms.push(PluralArm { selector: selector, result: pieces });
590 }
591 self.ws();
592 match self.cur.clone().next() {
593 Some((_, '}')) => { break }
594 Some(..) | None => {}
595 }
596 }
597
598 let other = match other {
599 Some(arm) => { arm }
600 None => {
601 self.err("`plural` statement must provide an `other` case");
602 vec!()
603 }
604 };
605 box Plural(offset, arms, other)
606 }
607
608 /// Parses a Count parameter at the current position. This does not check
609 /// for 'CountIsNextParam' because that is only used in precision, not
610 /// width.
611 fn count(&mut self) -> Count<'a> {
612 match self.integer() {
613 Some(i) => {
614 if self.consume('$') {
615 CountIsParam(i)
616 } else {
617 CountIs(i)
618 }
619 }
620 None => {
621 let tmp = self.cur.clone();
622 match self.word() {
623 word if word.len() > 0 && self.consume('$') => {
624 CountIsName(word)
625 }
626 _ => {
627 self.cur = tmp;
628 CountImplied
629 }
630 }
631 }
632 }
633 }
634
635 /// Parses a word starting at the current position. A word is considered to
636 /// be an alphabetic character followed by any number of alphanumeric
637 /// characters.
638 fn word(&mut self) -> &'a str {
639 let start = match self.cur.clone().next() {
640 Some((pos, c)) if char::is_XID_start(c) => {
641 self.cur.next();
642 pos
643 }
644 Some(..) | None => { return self.input.slice(0, 0); }
645 };
646 let mut end;
647 loop {
648 match self.cur.clone().next() {
649 Some((_, c)) if char::is_XID_continue(c) => {
650 self.cur.next();
651 }
652 Some((pos, _)) => { end = pos; break }
653 None => { end = self.input.len(); break }
654 }
655 }
656 self.input.slice(start, end)
657 }
658
659 /// Optionally parses an integer at the current position. This doesn't deal
660 /// with overflow at all, it's just accumulating digits.
661 fn integer(&mut self) -> Option<uint> {
662 let mut cur = 0;
663 let mut found = false;
664 loop {
665 match self.cur.clone().next() {
666 Some((_, c)) => {
667 match char::to_digit(c, 10) {
668 Some(i) => {
669 cur = cur * 10 + i;
670 found = true;
671 self.cur.next();
672 }
673 None => { break }
674 }
675 }
676 None => { break }
677 }
678 }
679 if found {
680 return Some(cur);
681 } else {
682 return None;
683 }
684 }
685 }
686
687 #[cfg(test)]
688 mod tests {
689 use super::*;
690
691 fn same(fmt: &'static str, p: &[Piece<'static>]) {
692 let mut parser = Parser::new(fmt);
693 assert!(p == parser.collect::<Vec<Piece<'static>>>().as_slice());
694 }
695
696 fn fmtdflt() -> FormatSpec<'static> {
697 return FormatSpec {
698 fill: None,
699 align: AlignUnknown,
700 flags: 0,
701 precision: CountImplied,
702 width: CountImplied,
703 ty: "",
704 }
705 }
706
707 fn musterr(s: &str) {
708 let mut p = Parser::new(s);
709 p.next();
710 assert!(p.errors.len() != 0);
711 }
712
713 #[test]
714 fn simple() {
715 same("asdf", [String("asdf")]);
716 same("a\\{b", [String("a"), String("{b")]);
717 same("a\\#b", [String("a"), String("#b")]);
718 same("a\\}b", [String("a"), String("}b")]);
719 same("a\\}", [String("a"), String("}")]);
720 same("\\}", [String("}")]);
721 }
722
723 #[test] fn invalid01() { musterr("{") }
724 #[test] fn invalid02() { musterr("\\") }
725 #[test] fn invalid03() { musterr("\\a") }
726 #[test] fn invalid04() { musterr("{3a}") }
727 #[test] fn invalid05() { musterr("{:|}") }
728 #[test] fn invalid06() { musterr("{:>>>}") }
729
730 #[test]
731 fn format_nothing() {
732 same("{}", [Argument(Argument {
733 position: ArgumentNext,
734 format: fmtdflt(),
735 method: None,
736 })]);
737 }
738 #[test]
739 fn format_position() {
740 same("{3}", [Argument(Argument {
741 position: ArgumentIs(3),
742 format: fmtdflt(),
743 method: None,
744 })]);
745 }
746 #[test]
747 fn format_position_nothing_else() {
748 same("{3:}", [Argument(Argument {
749 position: ArgumentIs(3),
750 format: fmtdflt(),
751 method: None,
752 })]);
753 }
754 #[test]
755 fn format_type() {
756 same("{3:a}", [Argument(Argument {
757 position: ArgumentIs(3),
758 format: FormatSpec {
759 fill: None,
760 align: AlignUnknown,
761 flags: 0,
762 precision: CountImplied,
763 width: CountImplied,
764 ty: "a",
765 },
766 method: None,
767 })]);
768 }
769 #[test]
770 fn format_align_fill() {
771 same("{3:>}", [Argument(Argument {
772 position: ArgumentIs(3),
773 format: FormatSpec {
774 fill: None,
775 align: AlignRight,
776 flags: 0,
777 precision: CountImplied,
778 width: CountImplied,
779 ty: "",
780 },
781 method: None,
782 })]);
783 same("{3:0<}", [Argument(Argument {
784 position: ArgumentIs(3),
785 format: FormatSpec {
786 fill: Some('0'),
787 align: AlignLeft,
788 flags: 0,
789 precision: CountImplied,
790 width: CountImplied,
791 ty: "",
792 },
793 method: None,
794 })]);
795 same("{3:*<abcd}", [Argument(Argument {
796 position: ArgumentIs(3),
797 format: FormatSpec {
798 fill: Some('*'),
799 align: AlignLeft,
800 flags: 0,
801 precision: CountImplied,
802 width: CountImplied,
803 ty: "abcd",
804 },
805 method: None,
806 })]);
807 }
808 #[test]
809 fn format_counts() {
810 same("{:10s}", [Argument(Argument {
811 position: ArgumentNext,
812 format: FormatSpec {
813 fill: None,
814 align: AlignUnknown,
815 flags: 0,
816 precision: CountImplied,
817 width: CountIs(10),
818 ty: "s",
819 },
820 method: None,
821 })]);
822 same("{:10$.10s}", [Argument(Argument {
823 position: ArgumentNext,
824 format: FormatSpec {
825 fill: None,
826 align: AlignUnknown,
827 flags: 0,
828 precision: CountIs(10),
829 width: CountIsParam(10),
830 ty: "s",
831 },
832 method: None,
833 })]);
834 same("{:.*s}", [Argument(Argument {
835 position: ArgumentNext,
836 format: FormatSpec {
837 fill: None,
838 align: AlignUnknown,
839 flags: 0,
840 precision: CountIsNextParam,
841 width: CountImplied,
842 ty: "s",
843 },
844 method: None,
845 })]);
846 same("{:.10$s}", [Argument(Argument {
847 position: ArgumentNext,
848 format: FormatSpec {
849 fill: None,
850 align: AlignUnknown,
851 flags: 0,
852 precision: CountIsParam(10),
853 width: CountImplied,
854 ty: "s",
855 },
856 method: None,
857 })]);
858 same("{:a$.b$s}", [Argument(Argument {
859 position: ArgumentNext,
860 format: FormatSpec {
861 fill: None,
862 align: AlignUnknown,
863 flags: 0,
864 precision: CountIsName("b"),
865 width: CountIsName("a"),
866 ty: "s",
867 },
868 method: None,
869 })]);
870 }
871 #[test]
872 fn format_flags() {
873 same("{:-}", [Argument(Argument {
874 position: ArgumentNext,
875 format: FormatSpec {
876 fill: None,
877 align: AlignUnknown,
878 flags: (1 << FlagSignMinus as uint),
879 precision: CountImplied,
880 width: CountImplied,
881 ty: "",
882 },
883 method: None,
884 })]);
885 same("{:+#}", [Argument(Argument {
886 position: ArgumentNext,
887 format: FormatSpec {
888 fill: None,
889 align: AlignUnknown,
890 flags: (1 << FlagSignPlus as uint) | (1 << FlagAlternate as uint),
891 precision: CountImplied,
892 width: CountImplied,
893 ty: "",
894 },
895 method: None,
896 })]);
897 }
898 #[test]
899 fn format_mixture() {
900 same("abcd {3:a} efg", [String("abcd "), Argument(Argument {
901 position: ArgumentIs(3),
902 format: FormatSpec {
903 fill: None,
904 align: AlignUnknown,
905 flags: 0,
906 precision: CountImplied,
907 width: CountImplied,
908 ty: "a",
909 },
910 method: None,
911 }), String(" efg")]);
912 }
913
914 #[test]
915 fn select_simple() {
916 same("{, select, other { haha } }", [Argument(Argument{
917 position: ArgumentNext,
918 format: fmtdflt(),
919 method: Some(box Select(vec![], vec![String(" haha ")]))
920 })]);
921 same("{1, select, other { haha } }", [Argument(Argument{
922 position: ArgumentIs(1),
923 format: fmtdflt(),
924 method: Some(box Select(vec![], vec![String(" haha ")]))
925 })]);
926 same("{1, select, other {#} }", [Argument(Argument{
927 position: ArgumentIs(1),
928 format: fmtdflt(),
929 method: Some(box Select(vec![], vec![CurrentArgument]))
930 })]);
931 same("{1, select, other {{2, select, other {lol}}} }", [Argument(Argument{
932 position: ArgumentIs(1),
933 format: fmtdflt(),
934 method: Some(box Select(vec![], vec![Argument(Argument{
935 position: ArgumentIs(2),
936 format: fmtdflt(),
937 method: Some(box Select(vec![], vec![String("lol")]))
938 })])) // wat
939 })]);
940 }
941
942 #[test]
943 fn select_cases() {
944 same("{1, select, a{1} b{2} c{3} other{4} }", [Argument(Argument{
945 position: ArgumentIs(1),
946 format: fmtdflt(),
947 method: Some(box Select(vec![
948 SelectArm{ selector: "a", result: vec![String("1")] },
949 SelectArm{ selector: "b", result: vec![String("2")] },
950 SelectArm{ selector: "c", result: vec![String("3")] },
951 ], vec![String("4")]))
952 })]);
953 }
954
955 #[test] fn badselect01() { musterr("{select, }") }
956 #[test] fn badselect02() { musterr("{1, select}") }
957 #[test] fn badselect03() { musterr("{1, select, }") }
958 #[test] fn badselect04() { musterr("{1, select, a {}}") }
959 #[test] fn badselect05() { musterr("{1, select, other }}") }
960 #[test] fn badselect06() { musterr("{1, select, other {}") }
961 #[test] fn badselect07() { musterr("{select, other {}") }
962 #[test] fn badselect08() { musterr("{1 select, other {}") }
963 #[test] fn badselect09() { musterr("{:d select, other {}") }
964 #[test] fn badselect10() { musterr("{1:d select, other {}") }
965
966 #[test]
967 fn plural_simple() {
968 same("{, plural, other { haha } }", [Argument(Argument{
969 position: ArgumentNext,
970 format: fmtdflt(),
971 method: Some(box Plural(None, vec![], vec![String(" haha ")]))
972 })]);
973 same("{:, plural, other { haha } }", [Argument(Argument{
974 position: ArgumentNext,
975 format: fmtdflt(),
976 method: Some(box Plural(None, vec![], vec![String(" haha ")]))
977 })]);
978 same("{, plural, offset:1 =2{2} =3{3} many{yes} other{haha} }",
979 [Argument(Argument{
980 position: ArgumentNext,
981 format: fmtdflt(),
982 method: Some(box Plural(Some(1), vec![
983 PluralArm{ selector: Literal(2), result: vec![String("2")] },
984 PluralArm{ selector: Literal(3), result: vec![String("3")] },
985 PluralArm{ selector: Keyword(Many), result: vec![String("yes")] }
986 ], vec![String("haha")]))
987 })]);
988 }
989 }
libfmt_macros/lib.rs:72:16-72:16 -enum- definition:
pub enum Position<'a> {
/// The argument will be in the next position. This is the default.
ArgumentNext,
references:- 571: /// Enum describing where an argument for a format can be located.
73: pub enum Position<'a> {
--
351: /// integer index of an argument, a named argument, or a blank string.
352: fn position(&mut self) -> Position<'a> {
353: match self.integer() {
libfmt_macros/lib.rs:53:16-53:16 -struct- definition:
pub struct FormatSpec<'a> {
/// Optionally specified character to fill alignment with
pub fill: Option<char>,
references:- 10368: fn format(&mut self) -> FormatSpec<'a> {
369: let mut spec = FormatSpec {
370: fill: None,
libfmt_macros/lib.rs:149:31-149:31 -enum- definition:
pub enum PluralSelector {
/// One of the plural keywords should be used
Keyword(PluralKeyword),
references:- 6148: /// A selector for what pluralization a plural method should take
150: pub enum PluralSelector {
--
161: /// literal.
162: pub selector: PluralSelector,
163: /// Array of pieces which are the format of this arm
libfmt_macros/lib.rs:111:16-111:16 -enum- definition:
pub enum Count<'a> {
/// The count is specified explicitly.
CountIs(uint),
references:- 6610: /// width.
611: fn count(&mut self) -> Count<'a> {
612: match self.integer() {
libfmt_macros/lib.rs:29:16-29:16 -enum- definition:
pub enum Piece<'a> {
/// A literal string which should directly be emitted
String(&'a str),
references:- 928: /// to emit. These are emitted as a stream by the `Parser` class.
30: pub enum Piece<'a> {
--
209: impl<'a> Iterator<Piece<'a>> for Parser<'a> {
210: fn next(&mut self) -> Option<Piece<'a>> {
211: match self.cur.clone().next() {
libfmt_macros/lib.rs:158:16-158:16 -struct- definition:
pub struct PluralArm<'a> {
/// A selector can either be specified by a keyword or with an integer
/// literal.
references:- 9588: } else {
589: arms.push(PluralArm { selector: selector, result: pieces });
590: }
libfmt_macros/lib.rs:187:16-187:16 -struct- definition:
pub struct SelectArm<'a> {
/// String selector which guards this arm
pub selector: &'a str,
references:- 9490: } else {
491: arms.push(SelectArm { selector: selector, result: pieces });
492: }
libfmt_macros/lib.rs:95:16-95:16 -enum- definition:
pub enum Flag {
/// A `+` will be used to denote positive numbers.
FlagSignPlus,
references:- 394: /// flags is defined by the formatters themselves.
96: pub enum Flag {
libfmt_macros/lib.rs:127:16-127:16 -enum- definition:
pub enum Method<'a> {
/// A plural method selects on an integer over a list of either integer or
/// keyword-defined clauses. The meaning of the keywords is defined by the
references:- 7126: /// currently supports.
128: pub enum Method<'a> {
--
468: /// Parses a 'select' statement (after the initial 'select' word)
469: fn select(&mut self) -> Box<Method<'a>> {
470: let mut other = None;
--
510: /// Parses a 'plural' statement (after the initial 'plural' word)
511: fn plural(&mut self) -> Box<Method<'a>> {
512: let mut offset = None;
libfmt_macros/lib.rs:200:78-200:78 -struct- definition:
/// necessary there's probably lots of room for improvement performance-wise.
pub struct Parser<'a> {
input: &'a str,
references:- 4237: impl<'a> Parser<'a> {
238: /// Creates a new parser for the given format string
239: pub fn new<'a>(s: &'a str) -> Parser<'a> {
240: Parser {
241: input: s,
libfmt_macros/lib.rs:172:22-172:22 -enum- definition:
pub enum PluralKeyword {
/// The plural form for zero objects.
Zero,
references:- 7170: /// http://www.icu-project.org/apiref/icu4c/classicu_1_1PluralRules.html
libfmt_macros/lib.rs:42:16-42:16 -struct- definition:
pub struct Argument<'a> {
/// Where to find this argument
pub position: Position<'a>,
references:- 10342: fn argument(&mut self) -> Argument<'a> {
343: Argument {
344: position: self.position(),
libfmt_macros/lib.rs:83:16-83:16 -enum- definition:
pub enum Alignment {
/// The value will be aligned to the left.
AlignLeft,
references:- 457: /// Optionally specified alignment
58: pub align: Alignment,
59: /// Packed version of various flags provided
--
82: /// Enum of alignments which are supported.
84: pub enum Alignment {