compiler/rustc_hir/src/target.rs

   1 //! This module implements some validity checks for attributes.
   2 //! In particular it verifies that `#[inline]` and `#[repr]` attributes are
   3 //! attached to items that actually support them and if there are
   4 //! conflicts between multiple such attributes attached to the same
   5 //! item.
   6
   7 use crate::hir;
   8 use crate::{Item, ItemKind, TraitItem, TraitItemKind};
   9
  10 use crate::def::DefKind;
  11 use std::fmt::{self, Display};
  12
  13 #[derive(Copy, Clone, PartialEq, Debug)]
  14 pub enum GenericParamKind {
  15     Type,
  16     Lifetime,
  17     Const,
  18 }
  19
  20 #[derive(Copy, Clone, PartialEq, Debug)]
  21 pub enum MethodKind {
  22     Trait { body: bool },
  23     Inherent,
  24 }
  25
  26 #[derive(Copy, Clone, PartialEq, Debug)]
  27 pub enum Target {
  28     ExternCrate,
  29     Use,
  30     Static,
  31     Const,
  32     Fn,
  33     Closure,
  34     Mod,
  35     ForeignMod,
  36     GlobalAsm,
  37     TyAlias,
  38     OpaqueTy,
  39     Enum,
  40     Variant,
  41     Struct,
  42     Field,
  43     Union,
  44     Trait,
  45     TraitAlias,
  46     Impl,
  47     Expression,
  48     Statement,
  49     Arm,
  50     AssocConst,
  51     Method(MethodKind),
  52     AssocTy,
  53     ForeignFn,
  54     ForeignStatic,
  55     ForeignTy,
  56     GenericParam(GenericParamKind),
  57     MacroDef,
  58     Param,
  59     PatField,
  60     ExprField,
  61 }
  62
  63 impl Display for Target {
  64     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
  65         write!(f, "{}", Self::name(*self))
  66     }
  67 }
  68
  69 impl Target {
  70     pub fn from_item(item: &Item<'_>) -> Target {
  71         match item.kind {
  72             ItemKind::ExternCrate(..) => Target::ExternCrate,
  73             ItemKind::Use(..) => Target::Use,
  74             ItemKind::Static(..) => Target::Static,
  75             ItemKind::Const(..) => Target::Const,
  76             ItemKind::Fn(..) => Target::Fn,
  77             ItemKind::Macro(..) => Target::MacroDef,
  78             ItemKind::Mod(..) => Target::Mod,
  79             ItemKind::ForeignMod { .. } => Target::ForeignMod,
  80             ItemKind::GlobalAsm(..) => Target::GlobalAsm,
  81             ItemKind::TyAlias(..) => Target::TyAlias,
  82             ItemKind::OpaqueTy(..) => Target::OpaqueTy,
  83             ItemKind::Enum(..) => Target::Enum,
  84             ItemKind::Struct(..) => Target::Struct,
  85             ItemKind::Union(..) => Target::Union,
  86             ItemKind::Trait(..) => Target::Trait,
  87             ItemKind::TraitAlias(..) => Target::TraitAlias,
  88             ItemKind::Impl { .. } => Target::Impl,
  89         }
  90     }
  91
  92     // FIXME: For now, should only be used with def_kinds from ItemIds
  93     pub fn from_def_kind(def_kind: DefKind) -> Target {
  94         match def_kind {
  95             DefKind::ExternCrate => Target::ExternCrate,
  96             DefKind::Use => Target::Use,
  97             DefKind::Static(..) => Target::Static,
  98             DefKind::Const => Target::Const,
  99             DefKind::Fn => Target::Fn,
 100             DefKind::Macro(..) => Target::MacroDef,
 101             DefKind::Mod => Target::Mod,
 102             DefKind::ForeignMod => Target::ForeignMod,
 103             DefKind::GlobalAsm => Target::GlobalAsm,
 104             DefKind::TyAlias => Target::TyAlias,
 105             DefKind::OpaqueTy => Target::OpaqueTy,
 106             DefKind::Enum => Target::Enum,
 107             DefKind::Struct => Target::Struct,
 108             DefKind::Union => Target::Union,
 109             DefKind::Trait => Target::Trait,
 110             DefKind::TraitAlias => Target::TraitAlias,
 111             DefKind::Impl => Target::Impl,
 112             _ => panic!("impossible case reached"),
 113         }
 114     }
 115
 116     pub fn from_trait_item(trait_item: &TraitItem<'_>) -> Target {
 117         match trait_item.kind {
 118             TraitItemKind::Const(..) => Target::AssocConst,
 119             TraitItemKind::Fn(_, hir::TraitFn::Required(_)) => {
 120                 Target::Method(MethodKind::Trait { body: false })
 121             }
 122             TraitItemKind::Fn(_, hir::TraitFn::Provided(_)) => {
 123                 Target::Method(MethodKind::Trait { body: true })
 124             }
 125             TraitItemKind::Type(..) => Target::AssocTy,
 126         }
 127     }
 128
 129     pub fn from_foreign_item(foreign_item: &hir::ForeignItem<'_>) -> Target {
 130         match foreign_item.kind {
 131             hir::ForeignItemKind::Fn(..) => Target::ForeignFn,
 132             hir::ForeignItemKind::Static(..) => Target::ForeignStatic,
 133             hir::ForeignItemKind::Type => Target::ForeignTy,
 134         }
 135     }
 136
 137     pub fn from_generic_param(generic_param: &hir::GenericParam<'_>) -> Target {
 138         match generic_param.kind {
 139             hir::GenericParamKind::Type { .. } => Target::GenericParam(GenericParamKind::Type),
 140             hir::GenericParamKind::Lifetime { .. } => {
 141                 Target::GenericParam(GenericParamKind::Lifetime)
 142             }
 143             hir::GenericParamKind::Const { .. } => Target::GenericParam(GenericParamKind::Const),
 144         }
 145     }
 146
 147     pub fn name(self) -> &'static str {
 148         match self {
 149             Target::ExternCrate => "extern crate",
 150             Target::Use => "use",
 151             Target::Static => "static item",
 152             Target::Const => "constant item",
 153             Target::Fn => "function",
 154             Target::Closure => "closure",
 155             Target::Mod => "module",
 156             Target::ForeignMod => "foreign module",
 157             Target::GlobalAsm => "global asm",
 158             Target::TyAlias => "type alias",
 159             Target::OpaqueTy => "opaque type",
 160             Target::Enum => "enum",
 161             Target::Variant => "enum variant",
 162             Target::Struct => "struct",
 163             Target::Field => "struct field",
 164             Target::Union => "union",
 165             Target::Trait => "trait",
 166             Target::TraitAlias => "trait alias",
 167             Target::Impl => "implementation block",
 168             Target::Expression => "expression",
 169             Target::Statement => "statement",
 170             Target::Arm => "match arm",
 171             Target::AssocConst => "associated const",
 172             Target::Method(kind) => match kind {
 173                 MethodKind::Inherent => "inherent method",
 174                 MethodKind::Trait { body: false } => "required trait method",
 175                 MethodKind::Trait { body: true } => "provided trait method",
 176             },
 177             Target::AssocTy => "associated type",
 178             Target::ForeignFn => "foreign function",
 179             Target::ForeignStatic => "foreign static item",
 180             Target::ForeignTy => "foreign type",
 181             Target::GenericParam(kind) => match kind {
 182                 GenericParamKind::Type => "type parameter",
 183                 GenericParamKind::Lifetime => "lifetime parameter",
 184                 GenericParamKind::Const => "const parameter",
 185             },
 186             Target::MacroDef => "macro def",
 187             Target::Param => "function param",
 188             Target::PatField => "pattern field",
 189             Target::ExprField => "struct field",
 190         }
 191     }
 192 }