CHANGELOG.md

Changelog

0.26.2

• #337: Fix missing generic impls for EnumTryAs
• #334: Support prefix in AsRefStr. Technically a breaking change, but prefix was just added in 0.26.0 so it's a newer feature and it makes the feature more consisent in general.

0.26.1

• #325: use core instead of std in VariantArray.

0.26.0

Breaking Changes

• The EnumVariantNames macro has been renamed VariantNames. The deprecation warning should steer you in the right direction for fixing the warning.
• The Iterator struct generated by EnumIter now has new bounds on it. This shouldn't break code unless you manually added the implementation in your code.
• Display now supports format strings using named fields in the enum variant. This should be a no-op for most code. However, if you were outputting a string like "Hello {field}", this will now be interpretted as a format string.
• EnumDiscriminant now inherits the repr and discriminant values from your main enum. This makes the discriminant type closer to a mirror of the original and that's always the goal.

New features

• The VariantArray macro has been added. This macro adds an associated constant VARIANTS to your enum. The constant is a &'static [Self] slice so that you can access all the variants of your enum. This only works on enums that only have unit variants.

  use strum::VariantArray;
  
  #[derive(Debug, VariantArray)]
  enum Color {
    Red,
    Blue,
    Green,
  }
  
  fn main() {
    println!("{:?}", Color::VARIANTS); // prints: ["Red", "Blue", "Green"]
  }

• The EnumTable macro has been experimentally added. This macro adds a new type that stores an item for each variant of the enum. This is useful for storing a value for each variant of an enum. This is an experimental feature because I'm not convinced the current api surface area is correct.

  use strum::EnumTable;
  
  #[derive(Copy, Clone, Debug, EnumTable)]
  enum Color {
    Red,
    Blue,
    Green,
  }
  
  fn main() {
    let mut counts = ColorTable::filled(0);
    for color in &[Color::Red, Color::Red, Color::Green]] {
      counts[color] += 1;
    }
  
    assert_eq!(counts[Color::Red], 2);
    assert_eq!(counts[Color::Blue], 0);
    assert_eq!(counts[Color::Green], 1);
  }

• Display has 2 new features:

  • the strum(prefix = "some_value") attribute on an enum now allows you to prepend a string onto every variant when you serialize it.

  • Custom to_string and serialize attributes now support string interopolation on serialization.

PR's Merged

• #322: avoid collisions on std::fmt::Debug
• #321: avoid conflicts with consecutive underscores.
• #314: add additional bounds to EnumIterator
• #311: add FusedIterator bounds to EnumIterator
• #297: New macro, add VariantArray
• #296: adds prefix attribute to To/From String macros.
• #294: use named enum fields in to_string macro.
• #288: discriminant enums now inherit the repr from the original enum.
• #279: Add EnumTable macro to generate a mapping between fieldless variants and data.

0.25.3 (strum_macros)

Received a number of bug fix PR's.

• #300: Fixes EnumIter for enums named Option.
• #301: Improved doc comments
• #304: Removed some unused Vec's
• #305: Added generic support to EnumIs

0.25.2 (strum_macros)

• #289: Enables a previously disabled rustdoc.
• #287: Fixes a bug in EnumIter code gen so that we produce ::core to avoid issues with shadowing modules.

0.25.1 (strum_macros)

• #276. Fixes #275 and #281. Not sure exactly why this broke, perhaps incompatibilities between syn 1 and 2. PR fixes the issue by only looking at attributes of the "list" type [attr(item, item)].

0.25.0

Breaking Changes

• #261 Upgrade syn dependency to version 2. This bumps the msrv to 1.56. It's impractical to maintain a package where a core dependency of the ecosystem has a different msrv than this one.

• 270 Change the to_string behavior when using default. Now, when using default, the display method will return the display version of the value contained in the enum rather than the name of the variant.

  #[derive(strum::Display)]
  enum Color {
    Red,
    Blue,
    Green,
    #[strum(default)]
    Other(String)
  }
  
  fn main() {
    // This used to print "Other", now it prints "Purple"
    assert_eq!(Color::Other("Purple".to_string()).to_string(), "Purple");
  }

  If you want the old behavior, you can use the to_string attribute to override this behavior. See the PR for an example.

• 268 Update the behavior of EnumCount to exclude variants that are disabled. This is a breaking change, but the behavior makes it more consistent with other methods.

New Features

• #257 This PR adds the EnumIs macro that automatically implements is_{variant_name} methods for each variant.

  #[derive(EnumIs)]
  enum Color {
      Red,
      Blue,
      Green,
  }
  
  #[test]
  fn simple_test() {
      assert!(Color::Red.is_red());
  }

0.24.3 (strum_macros)

• #231 Add ignore lints for EnumIter not implementing Copy or Debug on the generated iter struct. Copy should generally not be implemented on Iterators. Its an oversight that Debug isn't implemented, but it will be a breaking change to add that so it'll be added in a future version.

0.24.2 (strum_macros)

• #220. Add support for PHF in EnumString (opt-in runtime performance improvements for large enums as #[strum(use_phf)], requires phf feature and increases MSRV to 1.46)

  • #224 tweaked the algorithm.

• Reverted #217 because it was disruptive and non-trivial to work around if you hit it.

0.24.1 (Yanked becase #217 was more "breaking" than I wanted)

• #220. Add support for PHF in EnumString (opt-in runtime performance improvements for large enums as #[strum(use_phf)], requires phf feature and increases MSRV to 1.46)
  • #224 tweaked the algorithm.
• #217: Automatically implement TryFrom in FromRepr. This is technically a breaking change, but the fix is to just remove the manual implementation of TryFrom so it shouldn't be more than a minor inconvenience.

0.24.0

• #212. Fix some clippy lints

• #209. Use core instead of std in a few places.

• #206. Add get_documentation() to EnumMessage. This provides the ability to get the doc comment for a variant. Currently, very little formatting is done. That is subject to change. Please do not abuse this feature. Rust docs are meant for developer documentation, not long messages for users. However, this may be useful in some situations so we've added support for it.

• #202. Add a missing doc comment

• #201. Upgrade Heck version

0.23.1

• #193 Fixes an ambiguity introduced by #186 when your enum has a variant called Error.

• #192 The work done in #189 was lost in other PR's. This re-added the functionality to support no-std.

0.23.0

• #185 Adds the FromRepr derive that adds a from_repr(x: usize) -> Option<Self> method to your enum. This lets you convert integer values to your enum. If you specify a #[repr(..)] attribute on your enum, or use an explicit discriminant, this will be incorporated into the derive.

  • from_repr will be const if you use a recent rust version.
  • This cannot be a trait method currently because only inherent methods support const.

• #186 Automatically implement TryFrom<str> for enums that implement EnumString. This is only enabled for rustc >= 1.34 which is when `TryFrom was stabilized.

  • This is a small breaking change. If you had manually implemented TryFrom<str> for your enum, this will cause a conflict. You can probably remove your manual implementation.

• #189 Use core::result::Result instead of std::result::Result. This should be more portable in no-std environments.

0.22.0

• #180: Deprecates ToString derive. You should use Display instead.

• #178: Deprecates AsStaticStr. This has been undocumented for a while. The recommended method is to derive IntoStaticStr instead.

• #171: Improve no-std support.

• #170: enable changing the path to strum traits. This is necessary if you re-export strum as a submodule in another crate.

0.21.1

• #164 Improve compatibility with older versions of syn.

0.21.0

• Replace std:: with core:: to support no-std projects. #145

• Breaking Changes

  • MSRV is updated to 1.32 because heck does not work in 1.31.1 anymore. Rust 1.32 came out Jan 2019 so hopefully teams have moved to an equal or newer version.
  • #149 Remove the "rename" feature. In Rust 2018, macros should be imported using a qualified path to avoid collisions. strum_macros::EnumString rather than using the "Rename" feature to avoid collisions.
  • #160 enum messages: Make the returned values all 'static
    • It is unlikely this will break anyone, but the new signature for functions generated by EnumMessage is fn get_message(&self) -> Option<&'static str>.

• Added support for ascii_case_insensitive string comparisons. #157 This feature allows FromString impls to match strings that differ in case from the expected variant.

0.20.0

• Refactors to do better error handling. Thanks @jplatte for these changes

  • #133
  • #134
  • #135

• Adding vis(scope) to EnumDiscriminants. #137

  • This feature works best with versions of rust >= 1.34 due to a rustc parsing error in earlier versions.
  • Earlier versions can still use vis(r#pub)

• These changes should not be breaking, but the amount of code modified was significant.

• FYI about #122. The macro renames feature will be removed in early 2021. This feature was only necessary in rust 2015 because macros didn't support qualified imports so macro names could collide between crates.

0.19.4 / 0.19.5

• Updated docs

0.19.3

• Properly error on malformed strum attributes. #119
  • These types of inputs have historically been ignore silently. This may break code that is already incorrect.
• Move docs back to rust docs. #121
• Updated the docs a second time to improve discoverability.

0.19.2

• Fixes #104. PR #105

0.19.1

• Breaking Change: EnumVariantNames now properly adjusts to the to_string and serialize attributes.
• There's a regression in this release that may make strum imcompatible with other plugins if those plugins use non-rust syntax in their attributes. #104

0.19.0

• Fixed a regression using nth_back. #85

• Added repository to Cargo.toml. #90

• Correctly handle fill align in Display impls. #95

• Breaking Change: Use Associated Constant for EnumCount instead of const fn and free constant. #99 This behavior is consistent with the other derives.

• Breaking Change. default and disabled should now be written as markers instead of key value pairs. Here is the old way of adding these attributes to a variant.

  // OLD WAY
  enum Test {
    #[strum(disabled = "true", default = "true")]
    Variant(String)
  }

  Here is the new way. There is less ambiguity in the new syntax.

  enum Test {
    #[strum(disabled, default)]
    Variant(String)
  }

• Breaking Change. Most of the strum plugins will now error more aggresively on invalid options being used. Historically, the plugins have ignore invalid options, but most of these should error now. Silent errors are a rust anti-pattern.

0.18.0

• Only copy across "doc", "cfg", "allow", "deny" attributes from main enum variants to discriminant variants. #73
• The formatting of generated serialization variants returned by get_serializations() from an enum that derives EnumMessage is now affected by the serialize_all property on the enum. #84
• IntoEnumIterator now has the constraint IntoEnumIterator::Iterator<Item=Self> and Self: Sized. This makes it much easier to be generic over IntoEnumIterator and enum variants must be sized. [#80]

0.17.1

• Fixed an issue caused by combining #60 and #76

0.17.0

• Breaking Change. Enum variant names now exports an associated constant VARIANTS in the strum::VariantNames trait instead of adding a variants method directly to the enum. The fix is to use strum::VariantNames in your module and replace occurrances of variants() with VARIANTS.
  • #74
  • #75
• 🐛 fix - stop incrementing iterator index after we reach the end. #76
• Strum iterators now implemented DoubleEndedIterator. #60

0.16.0

• Added serialize UPPERCASE
• Added "case-styles" to match the formatting convention they imply such as kebab-case and camelCase.
• Added Enum Variant Names to improve compatibility with structopt and clap. #56
• Added derive re-export to strum to allow re-exporting macros from main crate. #57
• Bumped syn and quote to 1.0. This raises minimal compatible rust version to 1.31.
• Did internal refactoring to improve organization of code. Shouldn't change user-facing api though.
• Added license file to subdirectories so they are included in crate distros.

0.15.0

Added

• Added Feature flags to rename macros. This is to improve compatibility with older versions of rust. Wiki

0.14.0

Added

• Allow Missing Docs on EnumCount. PR #43
• Fix serialize_all in AsRefStr, AsStaticStr and IntoStaticStr. PR #42
  • This is a bug fix, but it may break code that was relying on the incorrect behavior.

0.13.0

Added

• Added a derive to implement From<YourEnum> for &'static str. This deprecates AsStaticStr since the new solution doesn't require a strum specific trait to use.

0.12.0

Added

• Serialization case can be controlled using #[strum(serialize_all = "snake_case")]. (#21)
• #[derive(EnumDiscriminants)] generates enum with variants without fields. (#33)

0.10.0

Added

• Implemented Clone for EnumIters. (#18)
• Added AsStaticRef derive to allow enums to impl AsStaticRef<str>. (#23)

Fixed

• #[allow(missing_docs)] on generated EnumIters. (#19)