src/libsyntax/edition.rs

   1 // Copyright 2018 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.
   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 use std::fmt;
  12 use std::str::FromStr;
  13
  14 /// The edition of the compiler (RFC 2052)
  15 #[derive(Clone, Copy, Hash, PartialOrd, Ord, Eq, PartialEq, Debug)]
  16 #[non_exhaustive]
  17 pub enum Edition {
  18     // editions must be kept in order, newest to oldest
  19
  20     /// The 2015 edition
  21     Edition2015,
  22     /// The 2018 edition
  23     Edition2018,
  24
  25     // when adding new editions, be sure to update:
  26     //
  27     // - Update the `ALL_EDITIONS` const
  28     // - Update the EDITION_NAME_LIST const
  29     // - add a `rust_####()` function to the session
  30     // - update the enum in Cargo's sources as well
  31 }
  32
  33 // must be in order from oldest to newest
  34 pub const ALL_EDITIONS: &[Edition] = &[Edition::Edition2015, Edition::Edition2018];
  35
  36 pub const EDITION_NAME_LIST: &'static str = "2015|2018";
  37
  38 pub const DEFAULT_EDITION: Edition = Edition::Edition2015;
  39
  40 impl fmt::Display for Edition {
  41     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
  42         let s = match *self {
  43             Edition::Edition2015 => "2015",
  44             Edition::Edition2018 => "2018",
  45         };
  46         write!(f, "{}", s)
  47     }
  48 }
  49
  50 impl Edition {
  51     pub fn lint_name(&self) -> &'static str {
  52         match *self {
  53             Edition::Edition2015 => "rust_2015_breakage",
  54             Edition::Edition2018 => "rust_2018_breakage",
  55         }
  56     }
  57
  58     pub fn feature_name(&self) -> &'static str {
  59         match *self {
  60             Edition::Edition2015 => "rust_2015_preview",
  61             Edition::Edition2018 => "rust_2018_preview",
  62         }
  63     }
  64
  65     pub fn is_stable(&self) -> bool {
  66         match *self {
  67             Edition::Edition2015 => true,
  68             Edition::Edition2018 => false,
  69         }
  70     }
  71 }
  72
  73 impl FromStr for Edition {
  74     type Err = ();
  75     fn from_str(s: &str) -> Result<Self, ()> {
  76         match s {
  77             "2015" => Ok(Edition::Edition2015),
  78             "2018" => Ok(Edition::Edition2018),
  79             _ => Err(())
  80         }
  81     }
  82 }