1 // Copyright 2017 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
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.
11 //! Representation of a `#[doc(cfg(...))]` attribute.
13 // FIXME: Once RFC #1868 is implemented, switch to use those structures instead.
16 use std::fmt::{self, Write};
19 use syntax::symbol::Symbol;
20 use syntax::ast::{MetaItem, MetaItemKind, NestedMetaItem, NestedMetaItemKind, LitKind};
21 use syntax::parse::ParseSess;
22 use syntax::feature_gate::Features;
26 use html::escape::Escape;
28 #[derive(Clone, RustcEncodable, RustcDecodable, Debug, PartialEq, Eq, Hash)]
30 /// Accepts all configurations.
32 /// Denies all configurations.
34 /// A generic configuration option, e.g. `test` or `target_os = "linux"`.
35 Cfg(Symbol, Option<Symbol>),
36 /// Negate a configuration requirement, i.e. `not(x)`.
38 /// Union of a list of configuration requirements, i.e. `any(...)`.
40 /// Intersection of a list of configuration requirements, i.e. `all(...)`.
44 #[derive(PartialEq, Debug)]
45 pub struct InvalidCfgError {
46 pub msg: &'static str,
51 /// Parses a `NestedMetaItem` into a `Cfg`.
52 fn parse_nested(nested_cfg: &NestedMetaItem) -> Result<Cfg, InvalidCfgError> {
53 match nested_cfg.node {
54 NestedMetaItemKind::MetaItem(ref cfg) => Cfg::parse(cfg),
55 NestedMetaItemKind::Literal(ref lit) => Err(InvalidCfgError {
56 msg: "unexpected literal",
62 /// Parses a `MetaItem` into a `Cfg`.
64 /// The `MetaItem` should be the content of the `#[cfg(...)]`, e.g. `unix` or
65 /// `target_os = "redox"`.
67 /// If the content is not properly formatted, it will return an error indicating what and where
69 pub fn parse(cfg: &MetaItem) -> Result<Cfg, InvalidCfgError> {
70 let name = cfg.name();
72 MetaItemKind::Word => Ok(Cfg::Cfg(name, None)),
73 MetaItemKind::NameValue(ref lit) => match lit.node {
74 LitKind::Str(value, _) => Ok(Cfg::Cfg(name, Some(value))),
75 _ => Err(InvalidCfgError {
76 // FIXME: if the main #[cfg] syntax decided to support non-string literals,
77 // this should be changed as well.
78 msg: "value of cfg option should be a string literal",
82 MetaItemKind::List(ref items) => {
83 let mut sub_cfgs = items.iter().map(Cfg::parse_nested);
84 match &*name.as_str() {
85 "all" => sub_cfgs.fold(Ok(Cfg::True), |x, y| Ok(x? & y?)),
86 "any" => sub_cfgs.fold(Ok(Cfg::False), |x, y| Ok(x? | y?)),
87 "not" => if sub_cfgs.len() == 1 {
88 Ok(!sub_cfgs.next().unwrap()?)
91 msg: "expected 1 cfg-pattern",
95 _ => Err(InvalidCfgError {
96 msg: "invalid predicate",
104 /// Checks whether the given configuration can be matched in the current session.
106 /// Equivalent to `attr::cfg_matches`.
107 // FIXME: Actually make use of `features`.
108 pub fn matches(&self, parse_sess: &ParseSess, features: Option<&Features>) -> bool {
112 Cfg::Not(ref child) => !child.matches(parse_sess, features),
113 Cfg::All(ref sub_cfgs) => {
114 sub_cfgs.iter().all(|sub_cfg| sub_cfg.matches(parse_sess, features))
116 Cfg::Any(ref sub_cfgs) => {
117 sub_cfgs.iter().any(|sub_cfg| sub_cfg.matches(parse_sess, features))
119 Cfg::Cfg(name, value) => parse_sess.config.contains(&(name, value)),
123 /// Whether the configuration consists of just `Cfg` or `Not`.
124 fn is_simple(&self) -> bool {
126 Cfg::False | Cfg::True | Cfg::Cfg(..) | Cfg::Not(..) => true,
127 Cfg::All(..) | Cfg::Any(..) => false,
131 /// Whether the configuration consists of just `Cfg`, `Not` or `All`.
132 fn is_all(&self) -> bool {
134 Cfg::False | Cfg::True | Cfg::Cfg(..) | Cfg::Not(..) | Cfg::All(..) => true,
135 Cfg::Any(..) => false,
139 /// Renders the configuration for human display, as a short HTML description.
140 pub(crate) fn render_short_html(&self) -> String {
141 let mut msg = Html(self, true).to_string();
142 if self.should_capitalize_first_letter() {
143 if let Some(i) = msg.find(|c: char| c.is_ascii_alphanumeric()) {
144 msg[i .. i+1].make_ascii_uppercase();
150 /// Renders the configuration for long display, as a long HTML description.
151 pub(crate) fn render_long_html(&self) -> String {
152 let on = if self.should_use_with_in_description() {
158 let mut msg = format!("This is supported {} <strong>{}</strong>", on, Html(self, false));
159 if self.should_append_only_to_description() {
160 msg.push_str(" only");
166 fn should_capitalize_first_letter(&self) -> bool {
168 Cfg::False | Cfg::True | Cfg::Not(..) => true,
169 Cfg::Any(ref sub_cfgs) | Cfg::All(ref sub_cfgs) => {
170 sub_cfgs.first().map(Cfg::should_capitalize_first_letter).unwrap_or(false)
172 Cfg::Cfg(name, _) => match &*name.as_str() {
173 "debug_assertions" | "target_endian" => true,
179 fn should_append_only_to_description(&self) -> bool {
181 Cfg::False | Cfg::True => false,
182 Cfg::Any(..) | Cfg::All(..) | Cfg::Cfg(..) => true,
183 Cfg::Not(ref child) => match **child {
184 Cfg::Cfg(..) => true,
190 fn should_use_with_in_description(&self) -> bool {
192 Cfg::Cfg(ref name, _) if name == &"target_feature" => true,
198 impl ops::Not for Cfg {
200 fn not(self) -> Cfg {
202 Cfg::False => Cfg::True,
203 Cfg::True => Cfg::False,
204 Cfg::Not(cfg) => *cfg,
205 s => Cfg::Not(Box::new(s)),
210 impl ops::BitAndAssign for Cfg {
211 fn bitand_assign(&mut self, other: Cfg) {
212 match (self, other) {
213 (&mut Cfg::False, _) | (_, Cfg::True) => {},
214 (s, Cfg::False) => *s = Cfg::False,
215 (s @ &mut Cfg::True, b) => *s = b,
216 (&mut Cfg::All(ref mut a), Cfg::All(ref mut b)) => a.append(b),
217 (&mut Cfg::All(ref mut a), ref mut b) => a.push(mem::replace(b, Cfg::True)),
218 (s, Cfg::All(mut a)) => {
219 let b = mem::replace(s, Cfg::True);
224 let a = mem::replace(s, Cfg::True);
225 *s = Cfg::All(vec![a, b]);
231 impl ops::BitAnd for Cfg {
233 fn bitand(mut self, other: Cfg) -> Cfg {
239 impl ops::BitOrAssign for Cfg {
240 fn bitor_assign(&mut self, other: Cfg) {
241 match (self, other) {
242 (&mut Cfg::True, _) | (_, Cfg::False) => {},
243 (s, Cfg::True) => *s = Cfg::True,
244 (s @ &mut Cfg::False, b) => *s = b,
245 (&mut Cfg::Any(ref mut a), Cfg::Any(ref mut b)) => a.append(b),
246 (&mut Cfg::Any(ref mut a), ref mut b) => a.push(mem::replace(b, Cfg::True)),
247 (s, Cfg::Any(mut a)) => {
248 let b = mem::replace(s, Cfg::True);
253 let a = mem::replace(s, Cfg::True);
254 *s = Cfg::Any(vec![a, b]);
260 impl ops::BitOr for Cfg {
262 fn bitor(mut self, other: Cfg) -> Cfg {
268 /// Pretty-print wrapper for a `Cfg`. Also indicates whether the "short-form" rendering should be
270 struct Html<'a>(&'a Cfg, bool);
272 fn write_with_opt_paren<T: fmt::Display>(
273 fmt: &mut fmt::Formatter,
278 fmt.write_char('(')?;
282 fmt.write_char(')')?;
288 impl<'a> fmt::Display for Html<'a> {
289 fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
291 Cfg::Not(ref child) => match **child {
292 Cfg::Any(ref sub_cfgs) => {
293 let separator = if sub_cfgs.iter().all(Cfg::is_simple) {
298 for (i, sub_cfg) in sub_cfgs.iter().enumerate() {
299 fmt.write_str(if i == 0 { "neither " } else { separator })?;
300 write_with_opt_paren(fmt, !sub_cfg.is_all(), Html(sub_cfg, self.1))?;
304 ref simple @ Cfg::Cfg(..) => write!(fmt, "non-{}", Html(simple, self.1)),
305 ref c => write!(fmt, "not ({})", Html(c, self.1)),
308 Cfg::Any(ref sub_cfgs) => {
309 let separator = if sub_cfgs.iter().all(Cfg::is_simple) {
314 for (i, sub_cfg) in sub_cfgs.iter().enumerate() {
316 fmt.write_str(separator)?;
318 write_with_opt_paren(fmt, !sub_cfg.is_all(), Html(sub_cfg, self.1))?;
323 Cfg::All(ref sub_cfgs) => {
324 for (i, sub_cfg) in sub_cfgs.iter().enumerate() {
326 fmt.write_str(" and ")?;
328 write_with_opt_paren(fmt, !sub_cfg.is_simple(), Html(sub_cfg, self.1))?;
333 Cfg::True => fmt.write_str("everywhere"),
334 Cfg::False => fmt.write_str("nowhere"),
336 Cfg::Cfg(name, value) => {
337 let n = &*name.as_str();
338 let human_readable = match (n, value) {
339 ("unix", None) => "Unix",
340 ("windows", None) => "Windows",
341 ("debug_assertions", None) => "debug-assertions enabled",
342 ("target_os", Some(os)) => match &*os.as_str() {
343 "android" => "Android",
344 "bitrig" => "Bitrig",
345 "dragonfly" => "DragonFly BSD",
346 "emscripten" => "Emscripten",
347 "freebsd" => "FreeBSD",
348 "fuchsia" => "Fuchsia",
354 "netbsd" => "NetBSD",
355 "openbsd" => "OpenBSD",
357 "solaris" => "Solaris",
358 "windows" => "Windows",
361 ("target_arch", Some(arch)) => match &*arch.as_str() {
362 "aarch64" => "AArch64",
366 "mips64" => "MIPS-64",
367 "msp430" => "MSP430",
368 "powerpc" => "PowerPC",
369 "powerpc64" => "PowerPC-64",
371 "sparc64" => "SPARC64",
372 "wasm32" => "WebAssembly",
374 "x86_64" => "x86-64",
377 ("target_vendor", Some(vendor)) => match &*vendor.as_str() {
380 "rumprun" => "Rumprun",
384 ("target_env", Some(env)) => match &*env.as_str() {
388 "newlib" => "Newlib",
389 "uclibc" => "uClibc",
392 ("target_endian", Some(endian)) => return write!(fmt, "{}-endian", endian),
393 ("target_pointer_width", Some(bits)) => return write!(fmt, "{}-bit", bits),
394 ("target_feature", Some(feat)) =>
396 return write!(fmt, "<code>{}</code>", feat);
398 return write!(fmt, "target feature <code>{}</code>", feat);
402 if !human_readable.is_empty() {
403 fmt.write_str(human_readable)
404 } else if let Some(v) = value {
405 write!(fmt, "<code>{}=\"{}\"</code>", Escape(n), Escape(&*v.as_str()))
407 write!(fmt, "<code>{}</code>", Escape(n))
418 use syntax::symbol::Symbol;
420 use syntax::source_map::dummy_spanned;
421 use syntax_pos::DUMMY_SP;
422 use syntax::with_globals;
424 fn word_cfg(s: &str) -> Cfg {
425 Cfg::Cfg(Symbol::intern(s), None)
428 fn name_value_cfg(name: &str, value: &str) -> Cfg {
429 Cfg::Cfg(Symbol::intern(name), Some(Symbol::intern(value)))
432 fn dummy_meta_item_word(name: &str) -> MetaItem {
434 ident: Path::from_ident(Ident::from_str(name)),
435 node: MetaItemKind::Word,
440 macro_rules! dummy_meta_item_list {
441 ($name:ident, [$($list:ident),* $(,)*]) => {
443 ident: Path::from_ident(Ident::from_str(stringify!($name))),
444 node: MetaItemKind::List(vec![
446 dummy_spanned(NestedMetaItemKind::MetaItem(
447 dummy_meta_item_word(stringify!($list)),
455 ($name:ident, [$($list:expr),* $(,)*]) => {
457 ident: Path::from_ident(Ident::from_str(stringify!($name))),
458 node: MetaItemKind::List(vec![
460 dummy_spanned(NestedMetaItemKind::MetaItem($list)),
471 assert_eq!(!Cfg::False, Cfg::True);
472 assert_eq!(!Cfg::True, Cfg::False);
473 assert_eq!(!word_cfg("test"), Cfg::Not(Box::new(word_cfg("test"))));
475 !Cfg::All(vec![word_cfg("a"), word_cfg("b")]),
476 Cfg::Not(Box::new(Cfg::All(vec![word_cfg("a"), word_cfg("b")])))
479 !Cfg::Any(vec![word_cfg("a"), word_cfg("b")]),
480 Cfg::Not(Box::new(Cfg::Any(vec![word_cfg("a"), word_cfg("b")])))
482 assert_eq!(!Cfg::Not(Box::new(word_cfg("test"))), word_cfg("test"));
489 let mut x = Cfg::False;
491 assert_eq!(x, Cfg::False);
493 x = word_cfg("test");
495 assert_eq!(x, Cfg::False);
497 x = word_cfg("test2");
499 assert_eq!(x, word_cfg("test2"));
502 x &= word_cfg("test3");
503 assert_eq!(x, word_cfg("test3"));
505 x &= word_cfg("test4");
506 assert_eq!(x, Cfg::All(vec![word_cfg("test3"), word_cfg("test4")]));
508 x &= word_cfg("test5");
509 assert_eq!(x, Cfg::All(vec![word_cfg("test3"), word_cfg("test4"), word_cfg("test5")]));
511 x &= Cfg::All(vec![word_cfg("test6"), word_cfg("test7")]);
512 assert_eq!(x, Cfg::All(vec![
520 let mut y = Cfg::Any(vec![word_cfg("a"), word_cfg("b")]);
522 assert_eq!(y, Cfg::All(vec![
528 Cfg::Any(vec![word_cfg("a"), word_cfg("b")]),
532 word_cfg("a") & word_cfg("b") & word_cfg("c"),
533 Cfg::All(vec![word_cfg("a"), word_cfg("b"), word_cfg("c")])
541 let mut x = Cfg::True;
543 assert_eq!(x, Cfg::True);
545 x = word_cfg("test");
547 assert_eq!(x, Cfg::True);
549 x = word_cfg("test2");
551 assert_eq!(x, word_cfg("test2"));
554 x |= word_cfg("test3");
555 assert_eq!(x, word_cfg("test3"));
557 x |= word_cfg("test4");
558 assert_eq!(x, Cfg::Any(vec![word_cfg("test3"), word_cfg("test4")]));
560 x |= word_cfg("test5");
561 assert_eq!(x, Cfg::Any(vec![word_cfg("test3"), word_cfg("test4"), word_cfg("test5")]));
563 x |= Cfg::Any(vec![word_cfg("test6"), word_cfg("test7")]);
564 assert_eq!(x, Cfg::Any(vec![
572 let mut y = Cfg::All(vec![word_cfg("a"), word_cfg("b")]);
574 assert_eq!(y, Cfg::Any(vec![
580 Cfg::All(vec![word_cfg("a"), word_cfg("b")]),
584 word_cfg("a") | word_cfg("b") | word_cfg("c"),
585 Cfg::Any(vec![word_cfg("a"), word_cfg("b"), word_cfg("c")])
593 let mi = dummy_meta_item_word("all");
594 assert_eq!(Cfg::parse(&mi), Ok(word_cfg("all")));
597 ident: Path::from_ident(Ident::from_str("all")),
598 node: MetaItemKind::NameValue(dummy_spanned(LitKind::Str(
599 Symbol::intern("done"),
604 assert_eq!(Cfg::parse(&mi), Ok(name_value_cfg("all", "done")));
606 let mi = dummy_meta_item_list!(all, [a, b]);
607 assert_eq!(Cfg::parse(&mi), Ok(word_cfg("a") & word_cfg("b")));
609 let mi = dummy_meta_item_list!(any, [a, b]);
610 assert_eq!(Cfg::parse(&mi), Ok(word_cfg("a") | word_cfg("b")));
612 let mi = dummy_meta_item_list!(not, [a]);
613 assert_eq!(Cfg::parse(&mi), Ok(!word_cfg("a")));
615 let mi = dummy_meta_item_list!(not, [
616 dummy_meta_item_list!(any, [
617 dummy_meta_item_word("a"),
618 dummy_meta_item_list!(all, [b, c]),
621 assert_eq!(Cfg::parse(&mi), Ok(!(word_cfg("a") | (word_cfg("b") & word_cfg("c")))));
623 let mi = dummy_meta_item_list!(all, [a, b, c]);
624 assert_eq!(Cfg::parse(&mi), Ok(word_cfg("a") & word_cfg("b") & word_cfg("c")));
629 fn test_parse_err() {
632 ident: Path::from_ident(Ident::from_str("foo")),
633 node: MetaItemKind::NameValue(dummy_spanned(LitKind::Bool(false))),
636 assert!(Cfg::parse(&mi).is_err());
638 let mi = dummy_meta_item_list!(not, [a, b]);
639 assert!(Cfg::parse(&mi).is_err());
641 let mi = dummy_meta_item_list!(not, []);
642 assert!(Cfg::parse(&mi).is_err());
644 let mi = dummy_meta_item_list!(foo, []);
645 assert!(Cfg::parse(&mi).is_err());
647 let mi = dummy_meta_item_list!(all, [
648 dummy_meta_item_list!(foo, []),
649 dummy_meta_item_word("b"),
651 assert!(Cfg::parse(&mi).is_err());
653 let mi = dummy_meta_item_list!(any, [
654 dummy_meta_item_word("a"),
655 dummy_meta_item_list!(foo, []),
657 assert!(Cfg::parse(&mi).is_err());
659 let mi = dummy_meta_item_list!(not, [
660 dummy_meta_item_list!(foo, []),
662 assert!(Cfg::parse(&mi).is_err());
667 fn test_render_short_html() {
670 word_cfg("unix").render_short_html(),
674 name_value_cfg("target_os", "macos").render_short_html(),
678 name_value_cfg("target_pointer_width", "16").render_short_html(),
682 name_value_cfg("target_endian", "little").render_short_html(),
686 (!word_cfg("windows")).render_short_html(),
690 (word_cfg("unix") & word_cfg("windows")).render_short_html(),
694 (word_cfg("unix") | word_cfg("windows")).render_short_html(),
699 word_cfg("unix") & word_cfg("windows") & word_cfg("debug_assertions")
700 ).render_short_html(),
701 "Unix and Windows and debug-assertions enabled"
705 word_cfg("unix") | word_cfg("windows") | word_cfg("debug_assertions")
706 ).render_short_html(),
707 "Unix or Windows or debug-assertions enabled"
711 !(word_cfg("unix") | word_cfg("windows") | word_cfg("debug_assertions"))
712 ).render_short_html(),
713 "Neither Unix nor Windows nor debug-assertions enabled"
717 (word_cfg("unix") & name_value_cfg("target_arch", "x86_64")) |
718 (word_cfg("windows") & name_value_cfg("target_pointer_width", "64"))
719 ).render_short_html(),
720 "Unix and x86-64, or Windows and 64-bit"
723 (!(word_cfg("unix") & word_cfg("windows"))).render_short_html(),
724 "Not (Unix and Windows)"
728 (word_cfg("debug_assertions") | word_cfg("windows")) & word_cfg("unix")
729 ).render_short_html(),
730 "(Debug-assertions enabled or Windows) and Unix"
733 name_value_cfg("target_feature", "sse2").render_short_html(),
738 name_value_cfg("target_arch", "x86_64") &
739 name_value_cfg("target_feature", "sse2")
740 ).render_short_html(),
741 "x86-64 and <code>sse2</code>"
747 fn test_render_long_html() {
750 word_cfg("unix").render_long_html(),
751 "This is supported on <strong>Unix</strong> only."
754 name_value_cfg("target_os", "macos").render_long_html(),
755 "This is supported on <strong>macOS</strong> only."
758 name_value_cfg("target_pointer_width", "16").render_long_html(),
759 "This is supported on <strong>16-bit</strong> only."
762 name_value_cfg("target_endian", "little").render_long_html(),
763 "This is supported on <strong>little-endian</strong> only."
766 (!word_cfg("windows")).render_long_html(),
767 "This is supported on <strong>non-Windows</strong> only."
770 (word_cfg("unix") & word_cfg("windows")).render_long_html(),
771 "This is supported on <strong>Unix and Windows</strong> only."
774 (word_cfg("unix") | word_cfg("windows")).render_long_html(),
775 "This is supported on <strong>Unix or Windows</strong> only."
779 word_cfg("unix") & word_cfg("windows") & word_cfg("debug_assertions")
780 ).render_long_html(),
781 "This is supported on <strong>Unix and Windows and debug-assertions enabled\
786 word_cfg("unix") | word_cfg("windows") | word_cfg("debug_assertions")
787 ).render_long_html(),
788 "This is supported on <strong>Unix or Windows or debug-assertions enabled\
793 !(word_cfg("unix") | word_cfg("windows") | word_cfg("debug_assertions"))
794 ).render_long_html(),
795 "This is supported on <strong>neither Unix nor Windows nor debug-assertions \
800 (word_cfg("unix") & name_value_cfg("target_arch", "x86_64")) |
801 (word_cfg("windows") & name_value_cfg("target_pointer_width", "64"))
802 ).render_long_html(),
803 "This is supported on <strong>Unix and x86-64, or Windows and 64-bit</strong> \
807 (!(word_cfg("unix") & word_cfg("windows"))).render_long_html(),
808 "This is supported on <strong>not (Unix and Windows)</strong>."
812 (word_cfg("debug_assertions") | word_cfg("windows")) & word_cfg("unix")
813 ).render_long_html(),
814 "This is supported on <strong>(debug-assertions enabled or Windows) and Unix\
818 name_value_cfg("target_feature", "sse2").render_long_html(),
819 "This is supported with <strong>target feature <code>sse2</code></strong> only."
823 name_value_cfg("target_arch", "x86_64") &
824 name_value_cfg("target_feature", "sse2")
825 ).render_long_html(),
826 "This is supported on <strong>x86-64 and target feature \
827 <code>sse2</code></strong> only."