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 std::fmt::{self, Display};
  11
  12 #[derive(Copy, Clone, PartialEq, Debug)]
  13 pub enum GenericParamKind {
  14     Type,
  15     Lifetime,
  16     Const,
  17 }
  18
  19 #[derive(Copy, Clone, PartialEq, Debug)]
  20 pub enum MethodKind {
  21     Trait { body: bool },
  22     Inherent,
  23 }
  24
  25 #[derive(Copy, Clone, PartialEq, Debug)]
  26 pub enum Target {
  27     ExternCrate,
  28     Use,
  29     Static,
  30     Const,
  31     Fn,
  32     Closure,
  33     Mod,
  34     ForeignMod,
  35     GlobalAsm,
  36     TyAlias,
  37     OpaqueTy,
  38     Enum,
  39     Variant,
  40     Struct,
  41     Field,
  42     Union,
  43     Trait,
  44     TraitAlias,
  45     Impl,
  46     Expression,
  47     Statement,
  48     Arm,
  49     AssocConst,
  50     Method(MethodKind),
  51     AssocTy,
  52     ForeignFn,
  53     ForeignStatic,
  54     ForeignTy,
  55     GenericParam(GenericParamKind),
  56     MacroDef,
  57     Param,
  58 }
  59
  60 impl Display for Target {
  61     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
  62         write!(
  63             f,
  64             "{}",
  65             match *self {
  66                 Target::ExternCrate => "extern crate",
  67                 Target::Use => "use",
  68                 Target::Static => "static item",
  69                 Target::Const => "constant item",
  70                 Target::Fn => "function",
  71                 Target::Closure => "closure",
  72                 Target::Mod => "module",
  73                 Target::ForeignMod => "foreign module",
  74                 Target::GlobalAsm => "global asm",
  75                 Target::TyAlias => "type alias",
  76                 Target::OpaqueTy => "opaque type",
  77                 Target::Enum => "enum",
  78                 Target::Variant => "enum variant",
  79                 Target::Struct => "struct",
  80                 Target::Field => "struct field",
  81                 Target::Union => "union",
  82                 Target::Trait => "trait",
  83                 Target::TraitAlias => "trait alias",
  84                 Target::Impl => "item",
  85                 Target::Expression => "expression",
  86                 Target::Statement => "statement",
  87                 Target::Arm => "match arm",
  88                 Target::AssocConst => "associated const",
  89                 Target::Method(kind) => match kind {
  90                     MethodKind::Inherent => "inherent method",
  91                     MethodKind::Trait { body: false } => "required trait method",
  92                     MethodKind::Trait { body: true } => "provided trait method",
  93                 },
  94                 Target::AssocTy => "associated type",
  95                 Target::ForeignFn => "foreign function",
  96                 Target::ForeignStatic => "foreign static item",
  97                 Target::ForeignTy => "foreign type",
  98                 Target::GenericParam(kind) => match kind {
  99                     GenericParamKind::Type => "type parameter",
 100                     GenericParamKind::Lifetime => "lifetime parameter",
 101                     GenericParamKind::Const => "const parameter",
 102                 },
 103                 Target::MacroDef => "macro def",
 104                 Target::Param => "function param",
 105             }
 106         )
 107     }
 108 }
 109
 110 impl Target {
 111     pub fn from_item(item: &Item<'_>) -> Target {
 112         match item.kind {
 113             ItemKind::ExternCrate(..) => Target::ExternCrate,
 114             ItemKind::Use(..) => Target::Use,
 115             ItemKind::Static(..) => Target::Static,
 116             ItemKind::Const(..) => Target::Const,
 117             ItemKind::Fn(..) => Target::Fn,
 118             ItemKind::Macro(..) => Target::MacroDef,
 119             ItemKind::Mod(..) => Target::Mod,
 120             ItemKind::ForeignMod { .. } => Target::ForeignMod,
 121             ItemKind::GlobalAsm(..) => Target::GlobalAsm,
 122             ItemKind::TyAlias(..) => Target::TyAlias,
 123             ItemKind::OpaqueTy(..) => Target::OpaqueTy,
 124             ItemKind::Enum(..) => Target::Enum,
 125             ItemKind::Struct(..) => Target::Struct,
 126             ItemKind::Union(..) => Target::Union,
 127             ItemKind::Trait(..) => Target::Trait,
 128             ItemKind::TraitAlias(..) => Target::TraitAlias,
 129             ItemKind::Impl { .. } => Target::Impl,
 130         }
 131     }
 132
 133     pub fn from_trait_item(trait_item: &TraitItem<'_>) -> Target {
 134         match trait_item.kind {
 135             TraitItemKind::Const(..) => Target::AssocConst,
 136             TraitItemKind::Fn(_, hir::TraitFn::Required(_)) => {
 137                 Target::Method(MethodKind::Trait { body: false })
 138             }
 139             TraitItemKind::Fn(_, hir::TraitFn::Provided(_)) => {
 140                 Target::Method(MethodKind::Trait { body: true })
 141             }
 142             TraitItemKind::Type(..) => Target::AssocTy,
 143         }
 144     }
 145
 146     pub fn from_foreign_item(foreign_item: &hir::ForeignItem<'_>) -> Target {
 147         match foreign_item.kind {
 148             hir::ForeignItemKind::Fn(..) => Target::ForeignFn,
 149             hir::ForeignItemKind::Static(..) => Target::ForeignStatic,
 150             hir::ForeignItemKind::Type => Target::ForeignTy,
 151         }
 152     }
 153
 154     pub fn from_generic_param(generic_param: &hir::GenericParam<'_>) -> Target {
 155         match generic_param.kind {
 156             hir::GenericParamKind::Type { .. } => Target::GenericParam(GenericParamKind::Type),
 157             hir::GenericParamKind::Lifetime { .. } => {
 158                 Target::GenericParam(GenericParamKind::Lifetime)
 159             }
 160             hir::GenericParamKind::Const { .. } => Target::GenericParam(GenericParamKind::Const),
 161         }
 162     }
 163 }