src/librustc_middle/middle/privacy.rs

   1 //! A pass that checks to make sure private fields and methods aren't used
   2 //! outside their scopes. This pass will also generate a set of exported items
   3 //! which are available for use externally when compiled as a library.
   4
   5 use rustc_data_structures::fx::FxHashMap;
   6 use rustc_hir::def_id::DefIdSet;
   7 use rustc_hir::HirId;
   8 use rustc_macros::HashStable;
   9 use std::fmt;
  10 use std::hash::Hash;
  11
  12 // Accessibility levels, sorted in ascending order
  13 #[derive(Clone, Copy, Debug, PartialEq, Eq, PartialOrd, Ord, HashStable)]
  14 pub enum AccessLevel {
  15     /// Superset of `AccessLevel::Reachable` used to mark impl Trait items.
  16     ReachableFromImplTrait,
  17     /// Exported items + items participating in various kinds of public interfaces,
  18     /// but not directly nameable. For example, if function `fn f() -> T {...}` is
  19     /// public, then type `T` is reachable. Its values can be obtained by other crates
  20     /// even if the type itself is not nameable.
  21     Reachable,
  22     /// Public items + items accessible to other crates with help of `pub use` re-exports
  23     Exported,
  24     /// Items accessible to other crates directly, without help of re-exports
  25     Public,
  26 }
  27
  28 // Accessibility levels for reachable HIR nodes
  29 #[derive(Clone)]
  30 pub struct AccessLevels<Id = HirId> {
  31     pub map: FxHashMap<Id, AccessLevel>,
  32 }
  33
  34 impl<Id: Hash + Eq> AccessLevels<Id> {
  35     /// See `AccessLevel::Reachable`.
  36     pub fn is_reachable(&self, id: Id) -> bool {
  37         self.map.get(&id) >= Some(&AccessLevel::Reachable)
  38     }
  39
  40     /// See `AccessLevel::Exported`.
  41     pub fn is_exported(&self, id: Id) -> bool {
  42         self.map.get(&id) >= Some(&AccessLevel::Exported)
  43     }
  44
  45     /// See `AccessLevel::Public`.
  46     pub fn is_public(&self, id: Id) -> bool {
  47         self.map.get(&id) >= Some(&AccessLevel::Public)
  48     }
  49 }
  50
  51 impl<Id: Hash + Eq> Default for AccessLevels<Id> {
  52     fn default() -> Self {
  53         AccessLevels { map: Default::default() }
  54     }
  55 }
  56
  57 impl<Id: Hash + Eq + fmt::Debug> fmt::Debug for AccessLevels<Id> {
  58     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
  59         fmt::Debug::fmt(&self.map, f)
  60     }
  61 }
  62
  63 /// A set containing all exported definitions from external crates.
  64 /// The set does not contain any entries from local crates.
  65 pub type ExternalExports = DefIdSet;