| //! The `HirDisplay` trait, which serves two purposes: Turning various bits from |
| //! HIR back into source code, and just displaying them for debugging/testing |
| //! purposes. |
| |
| use std::fmt::{self, Debug}; |
| |
| use base_db::CrateId; |
| use chalk_ir::BoundVar; |
| use hir_def::{ |
| body, |
| db::DefDatabase, |
| find_path, |
| generics::TypeParamProvenance, |
| intern::{Internable, Interned}, |
| item_scope::ItemInNs, |
| path::{Path, PathKind}, |
| type_ref::{TraitBoundModifier, TypeBound, TypeRef}, |
| visibility::Visibility, |
| HasModule, ItemContainerId, Lookup, ModuleId, TraitId, |
| }; |
| use hir_expand::{hygiene::Hygiene, name::Name}; |
| use itertools::Itertools; |
| use syntax::SmolStr; |
| |
| use crate::{ |
| const_from_placeholder_idx, |
| db::HirDatabase, |
| from_assoc_type_id, from_foreign_def_id, from_placeholder_idx, lt_from_placeholder_idx, |
| mapping::from_chalk, |
| primitive, subst_prefix, to_assoc_type_id, |
| utils::{self, generics}, |
| AdtId, AliasEq, AliasTy, CallableDefId, CallableSig, Const, ConstValue, DomainGoal, GenericArg, |
| ImplTraitId, Interner, Lifetime, LifetimeData, LifetimeOutlives, Mutability, OpaqueTy, |
| ProjectionTy, ProjectionTyExt, QuantifiedWhereClause, Scalar, TraitRef, TraitRefExt, Ty, TyExt, |
| TyKind, WhereClause, |
| }; |
| |
| pub struct HirFormatter<'a> { |
| pub db: &'a dyn HirDatabase, |
| fmt: &'a mut dyn fmt::Write, |
| buf: String, |
| curr_size: usize, |
| pub(crate) max_size: Option<usize>, |
| omit_verbose_types: bool, |
| display_target: DisplayTarget, |
| } |
| |
| pub trait HirDisplay { |
| fn hir_fmt(&self, f: &mut HirFormatter) -> Result<(), HirDisplayError>; |
| |
| /// Returns a `Display`able type that is human-readable. |
| fn into_displayable<'a>( |
| &'a self, |
| db: &'a dyn HirDatabase, |
| max_size: Option<usize>, |
| omit_verbose_types: bool, |
| display_target: DisplayTarget, |
| ) -> HirDisplayWrapper<'a, Self> |
| where |
| Self: Sized, |
| { |
| assert!( |
| !matches!(display_target, DisplayTarget::SourceCode { .. }), |
| "HirDisplayWrapper cannot fail with DisplaySourceCodeError, use HirDisplay::hir_fmt directly instead" |
| ); |
| HirDisplayWrapper { db, t: self, max_size, omit_verbose_types, display_target } |
| } |
| |
| /// Returns a `Display`able type that is human-readable. |
| /// Use this for showing types to the user (e.g. diagnostics) |
| fn display<'a>(&'a self, db: &'a dyn HirDatabase) -> HirDisplayWrapper<'a, Self> |
| where |
| Self: Sized, |
| { |
| HirDisplayWrapper { |
| db, |
| t: self, |
| max_size: None, |
| omit_verbose_types: false, |
| display_target: DisplayTarget::Diagnostics, |
| } |
| } |
| |
| /// Returns a `Display`able type that is human-readable and tries to be succinct. |
| /// Use this for showing types to the user where space is constrained (e.g. doc popups) |
| fn display_truncated<'a>( |
| &'a self, |
| db: &'a dyn HirDatabase, |
| max_size: Option<usize>, |
| ) -> HirDisplayWrapper<'a, Self> |
| where |
| Self: Sized, |
| { |
| HirDisplayWrapper { |
| db, |
| t: self, |
| max_size, |
| omit_verbose_types: true, |
| display_target: DisplayTarget::Diagnostics, |
| } |
| } |
| |
| /// Returns a String representation of `self` that can be inserted into the given module. |
| /// Use this when generating code (e.g. assists) |
| fn display_source_code<'a>( |
| &'a self, |
| db: &'a dyn HirDatabase, |
| module_id: ModuleId, |
| ) -> Result<String, DisplaySourceCodeError> { |
| let mut result = String::new(); |
| match self.hir_fmt(&mut HirFormatter { |
| db, |
| fmt: &mut result, |
| buf: String::with_capacity(20), |
| curr_size: 0, |
| max_size: None, |
| omit_verbose_types: false, |
| display_target: DisplayTarget::SourceCode { module_id }, |
| }) { |
| Ok(()) => {} |
| Err(HirDisplayError::FmtError) => panic!("Writing to String can't fail!"), |
| Err(HirDisplayError::DisplaySourceCodeError(e)) => return Err(e), |
| }; |
| Ok(result) |
| } |
| |
| /// Returns a String representation of `self` for test purposes |
| fn display_test<'a>(&'a self, db: &'a dyn HirDatabase) -> HirDisplayWrapper<'a, Self> |
| where |
| Self: Sized, |
| { |
| HirDisplayWrapper { |
| db, |
| t: self, |
| max_size: None, |
| omit_verbose_types: false, |
| display_target: DisplayTarget::Test, |
| } |
| } |
| } |
| |
| impl<'a> HirFormatter<'a> { |
| pub fn write_joined<T: HirDisplay>( |
| &mut self, |
| iter: impl IntoIterator<Item = T>, |
| sep: &str, |
| ) -> Result<(), HirDisplayError> { |
| let mut first = true; |
| for e in iter { |
| if !first { |
| write!(self, "{}", sep)?; |
| } |
| first = false; |
| e.hir_fmt(self)?; |
| } |
| Ok(()) |
| } |
| |
| /// This allows using the `write!` macro directly with a `HirFormatter`. |
| pub fn write_fmt(&mut self, args: fmt::Arguments) -> Result<(), HirDisplayError> { |
| // We write to a buffer first to track output size |
| self.buf.clear(); |
| fmt::write(&mut self.buf, args)?; |
| self.curr_size += self.buf.len(); |
| |
| // Then we write to the internal formatter from the buffer |
| self.fmt.write_str(&self.buf).map_err(HirDisplayError::from) |
| } |
| |
| pub fn should_truncate(&self) -> bool { |
| match self.max_size { |
| Some(max_size) => self.curr_size >= max_size, |
| None => false, |
| } |
| } |
| |
| pub fn omit_verbose_types(&self) -> bool { |
| self.omit_verbose_types |
| } |
| } |
| |
| #[derive(Clone, Copy)] |
| pub enum DisplayTarget { |
| /// Display types for inlays, doc popups, autocompletion, etc... |
| /// Showing `{unknown}` or not qualifying paths is fine here. |
| /// There's no reason for this to fail. |
| Diagnostics, |
| /// Display types for inserting them in source files. |
| /// The generated code should compile, so paths need to be qualified. |
| SourceCode { module_id: ModuleId }, |
| /// Only for test purpose to keep real types |
| Test, |
| } |
| |
| impl DisplayTarget { |
| fn is_source_code(&self) -> bool { |
| matches!(self, Self::SourceCode { .. }) |
| } |
| fn is_test(&self) -> bool { |
| matches!(self, Self::Test) |
| } |
| } |
| |
| #[derive(Debug)] |
| pub enum DisplaySourceCodeError { |
| PathNotFound, |
| UnknownType, |
| Closure, |
| } |
| |
| pub enum HirDisplayError { |
| /// Errors that can occur when generating source code |
| DisplaySourceCodeError(DisplaySourceCodeError), |
| /// `FmtError` is required to be compatible with std::fmt::Display |
| FmtError, |
| } |
| impl From<fmt::Error> for HirDisplayError { |
| fn from(_: fmt::Error) -> Self { |
| Self::FmtError |
| } |
| } |
| |
| pub struct HirDisplayWrapper<'a, T> { |
| db: &'a dyn HirDatabase, |
| t: &'a T, |
| max_size: Option<usize>, |
| omit_verbose_types: bool, |
| display_target: DisplayTarget, |
| } |
| |
| impl<'a, T> fmt::Display for HirDisplayWrapper<'a, T> |
| where |
| T: HirDisplay, |
| { |
| fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { |
| match self.t.hir_fmt(&mut HirFormatter { |
| db: self.db, |
| fmt: f, |
| buf: String::with_capacity(20), |
| curr_size: 0, |
| max_size: self.max_size, |
| omit_verbose_types: self.omit_verbose_types, |
| display_target: self.display_target, |
| }) { |
| Ok(()) => Ok(()), |
| Err(HirDisplayError::FmtError) => Err(fmt::Error), |
| Err(HirDisplayError::DisplaySourceCodeError(_)) => { |
| // This should never happen |
| panic!("HirDisplay::hir_fmt failed with DisplaySourceCodeError when calling Display::fmt!") |
| } |
| } |
| } |
| } |
| |
| const TYPE_HINT_TRUNCATION: &str = "…"; |
| |
| impl<T: HirDisplay> HirDisplay for &'_ T { |
| fn hir_fmt(&self, f: &mut HirFormatter) -> Result<(), HirDisplayError> { |
| HirDisplay::hir_fmt(*self, f) |
| } |
| } |
| |
| impl<T: HirDisplay + Internable> HirDisplay for Interned<T> { |
| fn hir_fmt(&self, f: &mut HirFormatter) -> Result<(), HirDisplayError> { |
| HirDisplay::hir_fmt(self.as_ref(), f) |
| } |
| } |
| |
| impl HirDisplay for ProjectionTy { |
| fn hir_fmt(&self, f: &mut HirFormatter) -> Result<(), HirDisplayError> { |
| if f.should_truncate() { |
| return write!(f, "{}", TYPE_HINT_TRUNCATION); |
| } |
| |
| let trait_ = f.db.trait_data(self.trait_(f.db)); |
| write!(f, "<")?; |
| self.self_type_parameter(Interner).hir_fmt(f)?; |
| write!(f, " as {}", trait_.name)?; |
| if self.substitution.len(Interner) > 1 { |
| write!(f, "<")?; |
| f.write_joined(&self.substitution.as_slice(Interner)[1..], ", ")?; |
| write!(f, ">")?; |
| } |
| write!(f, ">::{}", f.db.type_alias_data(from_assoc_type_id(self.associated_ty_id)).name)?; |
| Ok(()) |
| } |
| } |
| |
| impl HirDisplay for OpaqueTy { |
| fn hir_fmt(&self, f: &mut HirFormatter) -> Result<(), HirDisplayError> { |
| if f.should_truncate() { |
| return write!(f, "{}", TYPE_HINT_TRUNCATION); |
| } |
| |
| self.substitution.at(Interner, 0).hir_fmt(f) |
| } |
| } |
| |
| impl HirDisplay for GenericArg { |
| fn hir_fmt(&self, f: &mut HirFormatter) -> Result<(), HirDisplayError> { |
| match self.interned() { |
| crate::GenericArgData::Ty(ty) => ty.hir_fmt(f), |
| crate::GenericArgData::Lifetime(lt) => lt.hir_fmt(f), |
| crate::GenericArgData::Const(c) => c.hir_fmt(f), |
| } |
| } |
| } |
| |
| impl HirDisplay for Const { |
| fn hir_fmt(&self, f: &mut HirFormatter) -> Result<(), HirDisplayError> { |
| let data = self.interned(); |
| match data.value { |
| ConstValue::BoundVar(idx) => idx.hir_fmt(f), |
| ConstValue::InferenceVar(..) => write!(f, "_"), |
| ConstValue::Placeholder(idx) => { |
| let id = const_from_placeholder_idx(f.db, idx); |
| let generics = generics(f.db.upcast(), id.parent); |
| let param_data = &generics.params.consts[id.local_id]; |
| write!(f, "{}", param_data.name) |
| } |
| ConstValue::Concrete(c) => write!(f, "{}", c.interned), |
| } |
| } |
| } |
| |
| impl HirDisplay for BoundVar { |
| fn hir_fmt(&self, f: &mut HirFormatter) -> Result<(), HirDisplayError> { |
| write!(f, "?{}.{}", self.debruijn.depth(), self.index) |
| } |
| } |
| |
| impl HirDisplay for Ty { |
| fn hir_fmt(&self, f: &mut HirFormatter) -> Result<(), HirDisplayError> { |
| if f.should_truncate() { |
| return write!(f, "{}", TYPE_HINT_TRUNCATION); |
| } |
| |
| match self.kind(Interner) { |
| TyKind::Never => write!(f, "!")?, |
| TyKind::Str => write!(f, "str")?, |
| TyKind::Scalar(Scalar::Bool) => write!(f, "bool")?, |
| TyKind::Scalar(Scalar::Char) => write!(f, "char")?, |
| &TyKind::Scalar(Scalar::Float(t)) => write!(f, "{}", primitive::float_ty_to_string(t))?, |
| &TyKind::Scalar(Scalar::Int(t)) => write!(f, "{}", primitive::int_ty_to_string(t))?, |
| &TyKind::Scalar(Scalar::Uint(t)) => write!(f, "{}", primitive::uint_ty_to_string(t))?, |
| TyKind::Slice(t) => { |
| write!(f, "[")?; |
| t.hir_fmt(f)?; |
| write!(f, "]")?; |
| } |
| TyKind::Array(t, c) => { |
| write!(f, "[")?; |
| t.hir_fmt(f)?; |
| write!(f, "; ")?; |
| c.hir_fmt(f)?; |
| write!(f, "]")?; |
| } |
| TyKind::Raw(m, t) | TyKind::Ref(m, _, t) => { |
| if matches!(self.kind(Interner), TyKind::Raw(..)) { |
| write!( |
| f, |
| "*{}", |
| match m { |
| Mutability::Not => "const ", |
| Mutability::Mut => "mut ", |
| } |
| )?; |
| } else { |
| write!( |
| f, |
| "&{}", |
| match m { |
| Mutability::Not => "", |
| Mutability::Mut => "mut ", |
| } |
| )?; |
| } |
| |
| // FIXME: all this just to decide whether to use parentheses... |
| let contains_impl_fn = |bounds: &[QuantifiedWhereClause]| { |
| bounds.iter().any(|bound| { |
| if let WhereClause::Implemented(trait_ref) = bound.skip_binders() { |
| let trait_ = trait_ref.hir_trait_id(); |
| fn_traits(f.db.upcast(), trait_).any(|it| it == trait_) |
| } else { |
| false |
| } |
| }) |
| }; |
| let (preds_to_print, has_impl_fn_pred) = match t.kind(Interner) { |
| TyKind::Dyn(dyn_ty) if dyn_ty.bounds.skip_binders().interned().len() > 1 => { |
| let bounds = dyn_ty.bounds.skip_binders().interned(); |
| (bounds.len(), contains_impl_fn(bounds)) |
| } |
| TyKind::Alias(AliasTy::Opaque(OpaqueTy { |
| opaque_ty_id, |
| substitution: parameters, |
| })) |
| | TyKind::OpaqueType(opaque_ty_id, parameters) => { |
| let impl_trait_id = |
| f.db.lookup_intern_impl_trait_id((*opaque_ty_id).into()); |
| if let ImplTraitId::ReturnTypeImplTrait(func, idx) = impl_trait_id { |
| let datas = |
| f.db.return_type_impl_traits(func) |
| .expect("impl trait id without data"); |
| let data = (*datas) |
| .as_ref() |
| .map(|rpit| rpit.impl_traits[idx as usize].bounds.clone()); |
| let bounds = data.substitute(Interner, parameters); |
| let mut len = bounds.skip_binders().len(); |
| |
| // Don't count Sized but count when it absent |
| // (i.e. when explicit ?Sized bound is set). |
| let default_sized = SizedByDefault::Sized { |
| anchor: func.lookup(f.db.upcast()).module(f.db.upcast()).krate(), |
| }; |
| let sized_bounds = bounds |
| .skip_binders() |
| .iter() |
| .filter(|b| { |
| matches!( |
| b.skip_binders(), |
| WhereClause::Implemented(trait_ref) |
| if default_sized.is_sized_trait( |
| trait_ref.hir_trait_id(), |
| f.db.upcast(), |
| ), |
| ) |
| }) |
| .count(); |
| match sized_bounds { |
| 0 => len += 1, |
| _ => { |
| len = len.saturating_sub(sized_bounds); |
| } |
| } |
| |
| (len, contains_impl_fn(bounds.skip_binders())) |
| } else { |
| (0, false) |
| } |
| } |
| _ => (0, false), |
| }; |
| |
| if has_impl_fn_pred && preds_to_print <= 2 { |
| return t.hir_fmt(f); |
| } |
| |
| if preds_to_print > 1 { |
| write!(f, "(")?; |
| t.hir_fmt(f)?; |
| write!(f, ")")?; |
| } else { |
| t.hir_fmt(f)?; |
| } |
| } |
| TyKind::Tuple(_, substs) => { |
| if substs.len(Interner) == 1 { |
| write!(f, "(")?; |
| substs.at(Interner, 0).hir_fmt(f)?; |
| write!(f, ",)")?; |
| } else { |
| write!(f, "(")?; |
| f.write_joined(&*substs.as_slice(Interner), ", ")?; |
| write!(f, ")")?; |
| } |
| } |
| TyKind::Function(fn_ptr) => { |
| let sig = CallableSig::from_fn_ptr(fn_ptr); |
| sig.hir_fmt(f)?; |
| } |
| TyKind::FnDef(def, parameters) => { |
| let def = from_chalk(f.db, *def); |
| let sig = f.db.callable_item_signature(def).substitute(Interner, parameters); |
| match def { |
| CallableDefId::FunctionId(ff) => { |
| write!(f, "fn {}", f.db.function_data(ff).name)? |
| } |
| CallableDefId::StructId(s) => write!(f, "{}", f.db.struct_data(s).name)?, |
| CallableDefId::EnumVariantId(e) => { |
| write!(f, "{}", f.db.enum_data(e.parent).variants[e.local_id].name)? |
| } |
| }; |
| if parameters.len(Interner) > 0 { |
| let generics = generics(f.db.upcast(), def.into()); |
| let (parent_params, self_param, type_params, _impl_trait_params) = |
| generics.provenance_split(); |
| let total_len = parent_params + self_param + type_params; |
| // We print all params except implicit impl Trait params. Still a bit weird; should we leave out parent and self? |
| if total_len > 0 { |
| write!(f, "<")?; |
| f.write_joined(¶meters.as_slice(Interner)[..total_len], ", ")?; |
| write!(f, ">")?; |
| } |
| } |
| write!(f, "(")?; |
| f.write_joined(sig.params(), ", ")?; |
| write!(f, ")")?; |
| let ret = sig.ret(); |
| if !ret.is_unit() { |
| write!(f, " -> ")?; |
| ret.hir_fmt(f)?; |
| } |
| } |
| TyKind::Adt(AdtId(def_id), parameters) => { |
| match f.display_target { |
| DisplayTarget::Diagnostics | DisplayTarget::Test => { |
| let name = match *def_id { |
| hir_def::AdtId::StructId(it) => f.db.struct_data(it).name.clone(), |
| hir_def::AdtId::UnionId(it) => f.db.union_data(it).name.clone(), |
| hir_def::AdtId::EnumId(it) => f.db.enum_data(it).name.clone(), |
| }; |
| write!(f, "{}", name)?; |
| } |
| DisplayTarget::SourceCode { module_id } => { |
| if let Some(path) = find_path::find_path( |
| f.db.upcast(), |
| ItemInNs::Types((*def_id).into()), |
| module_id, |
| ) { |
| write!(f, "{}", path)?; |
| } else { |
| return Err(HirDisplayError::DisplaySourceCodeError( |
| DisplaySourceCodeError::PathNotFound, |
| )); |
| } |
| } |
| } |
| |
| if parameters.len(Interner) > 0 { |
| let parameters_to_write = if f.display_target.is_source_code() |
| || f.omit_verbose_types() |
| { |
| match self |
| .as_generic_def(f.db) |
| .map(|generic_def_id| f.db.generic_defaults(generic_def_id)) |
| .filter(|defaults| !defaults.is_empty()) |
| { |
| None => parameters.as_slice(Interner), |
| Some(default_parameters) => { |
| let mut default_from = 0; |
| for (i, parameter) in parameters.iter(Interner).enumerate() { |
| match ( |
| parameter.assert_ty_ref(Interner).kind(Interner), |
| default_parameters.get(i), |
| ) { |
| (&TyKind::Error, _) | (_, None) => { |
| default_from = i + 1; |
| } |
| (_, Some(default_parameter)) => { |
| let actual_default = default_parameter |
| .clone() |
| .substitute(Interner, &subst_prefix(parameters, i)); |
| if parameter.assert_ty_ref(Interner) != &actual_default |
| { |
| default_from = i + 1; |
| } |
| } |
| } |
| } |
| ¶meters.as_slice(Interner)[0..default_from] |
| } |
| } |
| } else { |
| parameters.as_slice(Interner) |
| }; |
| if !parameters_to_write.is_empty() { |
| write!(f, "<")?; |
| |
| if f.display_target.is_source_code() { |
| let mut first = true; |
| for generic_arg in parameters_to_write { |
| if !first { |
| write!(f, ", ")?; |
| } |
| first = false; |
| |
| if generic_arg.ty(Interner).map(|ty| ty.kind(Interner)) |
| == Some(&TyKind::Error) |
| { |
| write!(f, "_")?; |
| } else { |
| generic_arg.hir_fmt(f)?; |
| } |
| } |
| } else { |
| f.write_joined(parameters_to_write, ", ")?; |
| } |
| |
| write!(f, ">")?; |
| } |
| } |
| } |
| TyKind::AssociatedType(assoc_type_id, parameters) => { |
| let type_alias = from_assoc_type_id(*assoc_type_id); |
| let trait_ = match type_alias.lookup(f.db.upcast()).container { |
| ItemContainerId::TraitId(it) => it, |
| _ => panic!("not an associated type"), |
| }; |
| let trait_ = f.db.trait_data(trait_); |
| let type_alias_data = f.db.type_alias_data(type_alias); |
| |
| // Use placeholder associated types when the target is test (https://rust-lang.github.io/chalk/book/clauses/type_equality.html#placeholder-associated-types) |
| if f.display_target.is_test() { |
| write!(f, "{}::{}", trait_.name, type_alias_data.name)?; |
| if parameters.len(Interner) > 0 { |
| write!(f, "<")?; |
| f.write_joined(&*parameters.as_slice(Interner), ", ")?; |
| write!(f, ">")?; |
| } |
| } else { |
| let projection_ty = ProjectionTy { |
| associated_ty_id: to_assoc_type_id(type_alias), |
| substitution: parameters.clone(), |
| }; |
| |
| projection_ty.hir_fmt(f)?; |
| } |
| } |
| TyKind::Foreign(type_alias) => { |
| let type_alias = f.db.type_alias_data(from_foreign_def_id(*type_alias)); |
| write!(f, "{}", type_alias.name)?; |
| } |
| TyKind::OpaqueType(opaque_ty_id, parameters) => { |
| let impl_trait_id = f.db.lookup_intern_impl_trait_id((*opaque_ty_id).into()); |
| match impl_trait_id { |
| ImplTraitId::ReturnTypeImplTrait(func, idx) => { |
| let datas = |
| f.db.return_type_impl_traits(func).expect("impl trait id without data"); |
| let data = (*datas) |
| .as_ref() |
| .map(|rpit| rpit.impl_traits[idx as usize].bounds.clone()); |
| let bounds = data.substitute(Interner, ¶meters); |
| let krate = func.lookup(f.db.upcast()).module(f.db.upcast()).krate(); |
| write_bounds_like_dyn_trait_with_prefix( |
| "impl", |
| bounds.skip_binders(), |
| SizedByDefault::Sized { anchor: krate }, |
| f, |
| )?; |
| // FIXME: it would maybe be good to distinguish this from the alias type (when debug printing), and to show the substitution |
| } |
| ImplTraitId::AsyncBlockTypeImplTrait(..) => { |
| write!(f, "impl Future<Output = ")?; |
| parameters.at(Interner, 0).hir_fmt(f)?; |
| write!(f, ">")?; |
| } |
| } |
| } |
| TyKind::Closure(.., substs) => { |
| if f.display_target.is_source_code() { |
| return Err(HirDisplayError::DisplaySourceCodeError( |
| DisplaySourceCodeError::Closure, |
| )); |
| } |
| let sig = substs.at(Interner, 0).assert_ty_ref(Interner).callable_sig(f.db); |
| if let Some(sig) = sig { |
| if sig.params().is_empty() { |
| write!(f, "||")?; |
| } else if f.should_truncate() { |
| write!(f, "|{}|", TYPE_HINT_TRUNCATION)?; |
| } else { |
| write!(f, "|")?; |
| f.write_joined(sig.params(), ", ")?; |
| write!(f, "|")?; |
| }; |
| |
| write!(f, " -> ")?; |
| sig.ret().hir_fmt(f)?; |
| } else { |
| write!(f, "{{closure}}")?; |
| } |
| } |
| TyKind::Placeholder(idx) => { |
| let id = from_placeholder_idx(f.db, *idx); |
| let generics = generics(f.db.upcast(), id.parent); |
| let param_data = &generics.params.types[id.local_id]; |
| match param_data.provenance { |
| TypeParamProvenance::TypeParamList | TypeParamProvenance::TraitSelf => { |
| write!(f, "{}", param_data.name.clone().unwrap_or_else(Name::missing))? |
| } |
| TypeParamProvenance::ArgumentImplTrait => { |
| let substs = generics.type_params_subst(f.db); |
| let bounds = |
| f.db.generic_predicates(id.parent) |
| .iter() |
| .map(|pred| pred.clone().substitute(Interner, &substs)) |
| .filter(|wc| match &wc.skip_binders() { |
| WhereClause::Implemented(tr) => { |
| &tr.self_type_parameter(Interner) == self |
| } |
| WhereClause::AliasEq(AliasEq { |
| alias: AliasTy::Projection(proj), |
| ty: _, |
| }) => &proj.self_type_parameter(Interner) == self, |
| _ => false, |
| }) |
| .collect::<Vec<_>>(); |
| let krate = id.parent.module(f.db.upcast()).krate(); |
| write_bounds_like_dyn_trait_with_prefix( |
| "impl", |
| &bounds, |
| SizedByDefault::Sized { anchor: krate }, |
| f, |
| )?; |
| } |
| } |
| } |
| TyKind::BoundVar(idx) => idx.hir_fmt(f)?, |
| TyKind::Dyn(dyn_ty) => { |
| write_bounds_like_dyn_trait_with_prefix( |
| "dyn", |
| dyn_ty.bounds.skip_binders().interned(), |
| SizedByDefault::NotSized, |
| f, |
| )?; |
| } |
| TyKind::Alias(AliasTy::Projection(p_ty)) => p_ty.hir_fmt(f)?, |
| TyKind::Alias(AliasTy::Opaque(opaque_ty)) => { |
| let impl_trait_id = f.db.lookup_intern_impl_trait_id(opaque_ty.opaque_ty_id.into()); |
| match impl_trait_id { |
| ImplTraitId::ReturnTypeImplTrait(func, idx) => { |
| let datas = |
| f.db.return_type_impl_traits(func).expect("impl trait id without data"); |
| let data = (*datas) |
| .as_ref() |
| .map(|rpit| rpit.impl_traits[idx as usize].bounds.clone()); |
| let bounds = data.substitute(Interner, &opaque_ty.substitution); |
| let krate = func.lookup(f.db.upcast()).module(f.db.upcast()).krate(); |
| write_bounds_like_dyn_trait_with_prefix( |
| "impl", |
| bounds.skip_binders(), |
| SizedByDefault::Sized { anchor: krate }, |
| f, |
| )?; |
| } |
| ImplTraitId::AsyncBlockTypeImplTrait(..) => { |
| write!(f, "{{async block}}")?; |
| } |
| }; |
| } |
| TyKind::Error => { |
| if f.display_target.is_source_code() { |
| return Err(HirDisplayError::DisplaySourceCodeError( |
| DisplaySourceCodeError::UnknownType, |
| )); |
| } |
| write!(f, "{{unknown}}")?; |
| } |
| TyKind::InferenceVar(..) => write!(f, "_")?, |
| TyKind::Generator(..) => write!(f, "{{generator}}")?, |
| TyKind::GeneratorWitness(..) => write!(f, "{{generator witness}}")?, |
| } |
| Ok(()) |
| } |
| } |
| |
| impl HirDisplay for CallableSig { |
| fn hir_fmt(&self, f: &mut HirFormatter) -> Result<(), HirDisplayError> { |
| write!(f, "fn(")?; |
| f.write_joined(self.params(), ", ")?; |
| if self.is_varargs { |
| if self.params().is_empty() { |
| write!(f, "...")?; |
| } else { |
| write!(f, ", ...")?; |
| } |
| } |
| write!(f, ")")?; |
| let ret = self.ret(); |
| if !ret.is_unit() { |
| write!(f, " -> ")?; |
| ret.hir_fmt(f)?; |
| } |
| Ok(()) |
| } |
| } |
| |
| fn fn_traits(db: &dyn DefDatabase, trait_: TraitId) -> impl Iterator<Item = TraitId> { |
| let krate = trait_.lookup(db).container.krate(); |
| utils::fn_traits(db, krate) |
| } |
| |
| #[derive(Clone, Copy, PartialEq, Eq)] |
| pub enum SizedByDefault { |
| NotSized, |
| Sized { anchor: CrateId }, |
| } |
| |
| impl SizedByDefault { |
| fn is_sized_trait(self, trait_: TraitId, db: &dyn DefDatabase) -> bool { |
| match self { |
| Self::NotSized => false, |
| Self::Sized { anchor } => { |
| let sized_trait = db |
| .lang_item(anchor, SmolStr::new_inline("sized")) |
| .and_then(|lang_item| lang_item.as_trait()); |
| Some(trait_) == sized_trait |
| } |
| } |
| } |
| } |
| |
| pub fn write_bounds_like_dyn_trait_with_prefix( |
| prefix: &str, |
| predicates: &[QuantifiedWhereClause], |
| default_sized: SizedByDefault, |
| f: &mut HirFormatter, |
| ) -> Result<(), HirDisplayError> { |
| write!(f, "{}", prefix)?; |
| if !predicates.is_empty() |
| || predicates.is_empty() && matches!(default_sized, SizedByDefault::Sized { .. }) |
| { |
| write!(f, " ")?; |
| write_bounds_like_dyn_trait(predicates, default_sized, f) |
| } else { |
| Ok(()) |
| } |
| } |
| |
| fn write_bounds_like_dyn_trait( |
| predicates: &[QuantifiedWhereClause], |
| default_sized: SizedByDefault, |
| f: &mut HirFormatter, |
| ) -> Result<(), HirDisplayError> { |
| // Note: This code is written to produce nice results (i.e. |
| // corresponding to surface Rust) for types that can occur in |
| // actual Rust. It will have weird results if the predicates |
| // aren't as expected (i.e. self types = $0, projection |
| // predicates for a certain trait come after the Implemented |
| // predicate for that trait). |
| let mut first = true; |
| let mut angle_open = false; |
| let mut is_fn_trait = false; |
| let mut is_sized = false; |
| for p in predicates.iter() { |
| match p.skip_binders() { |
| WhereClause::Implemented(trait_ref) => { |
| let trait_ = trait_ref.hir_trait_id(); |
| if default_sized.is_sized_trait(trait_, f.db.upcast()) { |
| is_sized = true; |
| if matches!(default_sized, SizedByDefault::Sized { .. }) { |
| // Don't print +Sized, but rather +?Sized if absent. |
| continue; |
| } |
| } |
| if !is_fn_trait { |
| is_fn_trait = fn_traits(f.db.upcast(), trait_).any(|it| it == trait_); |
| } |
| if !is_fn_trait && angle_open { |
| write!(f, ">")?; |
| angle_open = false; |
| } |
| if !first { |
| write!(f, " + ")?; |
| } |
| // We assume that the self type is ^0.0 (i.e. the |
| // existential) here, which is the only thing that's |
| // possible in actual Rust, and hence don't print it |
| write!(f, "{}", f.db.trait_data(trait_).name)?; |
| if let [_, params @ ..] = &*trait_ref.substitution.as_slice(Interner) { |
| if is_fn_trait { |
| if let Some(args) = |
| params.first().and_then(|it| it.assert_ty_ref(Interner).as_tuple()) |
| { |
| write!(f, "(")?; |
| f.write_joined(args.as_slice(Interner), ", ")?; |
| write!(f, ")")?; |
| } |
| } else if !params.is_empty() { |
| write!(f, "<")?; |
| f.write_joined(params, ", ")?; |
| // there might be assoc type bindings, so we leave the angle brackets open |
| angle_open = true; |
| } |
| } |
| } |
| WhereClause::AliasEq(alias_eq) if is_fn_trait => { |
| is_fn_trait = false; |
| if !alias_eq.ty.is_unit() { |
| write!(f, " -> ")?; |
| alias_eq.ty.hir_fmt(f)?; |
| } |
| } |
| WhereClause::AliasEq(AliasEq { ty, alias }) => { |
| // in types in actual Rust, these will always come |
| // after the corresponding Implemented predicate |
| if angle_open { |
| write!(f, ", ")?; |
| } else { |
| write!(f, "<")?; |
| angle_open = true; |
| } |
| if let AliasTy::Projection(proj) = alias { |
| let type_alias = |
| f.db.type_alias_data(from_assoc_type_id(proj.associated_ty_id)); |
| write!(f, "{} = ", type_alias.name)?; |
| } |
| ty.hir_fmt(f)?; |
| } |
| |
| // FIXME implement these |
| WhereClause::LifetimeOutlives(_) => {} |
| WhereClause::TypeOutlives(_) => {} |
| } |
| first = false; |
| } |
| if angle_open { |
| write!(f, ">")?; |
| } |
| if matches!(default_sized, SizedByDefault::Sized { .. }) { |
| if !is_sized { |
| write!(f, "{}?Sized", if first { "" } else { " + " })?; |
| } else if first { |
| write!(f, "Sized")?; |
| } |
| } |
| Ok(()) |
| } |
| |
| fn fmt_trait_ref(tr: &TraitRef, f: &mut HirFormatter, use_as: bool) -> Result<(), HirDisplayError> { |
| if f.should_truncate() { |
| return write!(f, "{}", TYPE_HINT_TRUNCATION); |
| } |
| |
| tr.self_type_parameter(Interner).hir_fmt(f)?; |
| if use_as { |
| write!(f, " as ")?; |
| } else { |
| write!(f, ": ")?; |
| } |
| write!(f, "{}", f.db.trait_data(tr.hir_trait_id()).name)?; |
| if tr.substitution.len(Interner) > 1 { |
| write!(f, "<")?; |
| f.write_joined(&tr.substitution.as_slice(Interner)[1..], ", ")?; |
| write!(f, ">")?; |
| } |
| Ok(()) |
| } |
| |
| impl HirDisplay for TraitRef { |
| fn hir_fmt(&self, f: &mut HirFormatter) -> Result<(), HirDisplayError> { |
| fmt_trait_ref(self, f, false) |
| } |
| } |
| |
| impl HirDisplay for WhereClause { |
| fn hir_fmt(&self, f: &mut HirFormatter) -> Result<(), HirDisplayError> { |
| if f.should_truncate() { |
| return write!(f, "{}", TYPE_HINT_TRUNCATION); |
| } |
| |
| match self { |
| WhereClause::Implemented(trait_ref) => trait_ref.hir_fmt(f)?, |
| WhereClause::AliasEq(AliasEq { alias: AliasTy::Projection(projection_ty), ty }) => { |
| write!(f, "<")?; |
| fmt_trait_ref(&projection_ty.trait_ref(f.db), f, true)?; |
| write!( |
| f, |
| ">::{} = ", |
| f.db.type_alias_data(from_assoc_type_id(projection_ty.associated_ty_id)).name, |
| )?; |
| ty.hir_fmt(f)?; |
| } |
| WhereClause::AliasEq(_) => write!(f, "{{error}}")?, |
| |
| // FIXME implement these |
| WhereClause::TypeOutlives(..) => {} |
| WhereClause::LifetimeOutlives(..) => {} |
| } |
| Ok(()) |
| } |
| } |
| |
| impl HirDisplay for LifetimeOutlives { |
| fn hir_fmt(&self, f: &mut HirFormatter) -> Result<(), HirDisplayError> { |
| self.a.hir_fmt(f)?; |
| write!(f, ": ")?; |
| self.b.hir_fmt(f) |
| } |
| } |
| |
| impl HirDisplay for Lifetime { |
| fn hir_fmt(&self, f: &mut HirFormatter) -> Result<(), HirDisplayError> { |
| self.interned().hir_fmt(f) |
| } |
| } |
| |
| impl HirDisplay for LifetimeData { |
| fn hir_fmt(&self, f: &mut HirFormatter) -> Result<(), HirDisplayError> { |
| match self { |
| LifetimeData::BoundVar(idx) => idx.hir_fmt(f), |
| LifetimeData::InferenceVar(_) => write!(f, "_"), |
| LifetimeData::Placeholder(idx) => { |
| let id = lt_from_placeholder_idx(f.db, *idx); |
| let generics = generics(f.db.upcast(), id.parent); |
| let param_data = &generics.params.lifetimes[id.local_id]; |
| write!(f, "{}", param_data.name) |
| } |
| LifetimeData::Static => write!(f, "'static"), |
| LifetimeData::Empty(_) => Ok(()), |
| LifetimeData::Erased => Ok(()), |
| LifetimeData::Phantom(_, _) => Ok(()), |
| } |
| } |
| } |
| |
| impl HirDisplay for DomainGoal { |
| fn hir_fmt(&self, f: &mut HirFormatter) -> Result<(), HirDisplayError> { |
| match self { |
| DomainGoal::Holds(wc) => { |
| write!(f, "Holds(")?; |
| wc.hir_fmt(f)?; |
| write!(f, ")")?; |
| } |
| _ => write!(f, "?")?, |
| } |
| Ok(()) |
| } |
| } |
| |
| pub fn write_visibility( |
| module_id: ModuleId, |
| vis: Visibility, |
| f: &mut HirFormatter, |
| ) -> Result<(), HirDisplayError> { |
| match vis { |
| Visibility::Public => write!(f, "pub "), |
| Visibility::Module(vis_id) => { |
| let def_map = module_id.def_map(f.db.upcast()); |
| let root_module_id = def_map.module_id(def_map.root()); |
| if vis_id == module_id { |
| // pub(self) or omitted |
| Ok(()) |
| } else if root_module_id == vis_id { |
| write!(f, "pub(crate) ") |
| } else if module_id.containing_module(f.db.upcast()) == Some(vis_id) { |
| write!(f, "pub(super) ") |
| } else { |
| write!(f, "pub(in ...) ") |
| } |
| } |
| } |
| } |
| |
| impl HirDisplay for TypeRef { |
| fn hir_fmt(&self, f: &mut HirFormatter) -> Result<(), HirDisplayError> { |
| match self { |
| TypeRef::Never => write!(f, "!")?, |
| TypeRef::Placeholder => write!(f, "_")?, |
| TypeRef::Tuple(elems) => { |
| write!(f, "(")?; |
| f.write_joined(elems, ", ")?; |
| if elems.len() == 1 { |
| write!(f, ",")?; |
| } |
| write!(f, ")")?; |
| } |
| TypeRef::Path(path) => path.hir_fmt(f)?, |
| TypeRef::RawPtr(inner, mutability) => { |
| let mutability = match mutability { |
| hir_def::type_ref::Mutability::Shared => "*const ", |
| hir_def::type_ref::Mutability::Mut => "*mut ", |
| }; |
| write!(f, "{}", mutability)?; |
| inner.hir_fmt(f)?; |
| } |
| TypeRef::Reference(inner, lifetime, mutability) => { |
| let mutability = match mutability { |
| hir_def::type_ref::Mutability::Shared => "", |
| hir_def::type_ref::Mutability::Mut => "mut ", |
| }; |
| write!(f, "&")?; |
| if let Some(lifetime) = lifetime { |
| write!(f, "{} ", lifetime.name)?; |
| } |
| write!(f, "{}", mutability)?; |
| inner.hir_fmt(f)?; |
| } |
| TypeRef::Array(inner, len) => { |
| write!(f, "[")?; |
| inner.hir_fmt(f)?; |
| write!(f, "; {}]", len)?; |
| } |
| TypeRef::Slice(inner) => { |
| write!(f, "[")?; |
| inner.hir_fmt(f)?; |
| write!(f, "]")?; |
| } |
| TypeRef::Fn(tys, is_varargs) => { |
| // FIXME: Function pointer qualifiers. |
| write!(f, "fn(")?; |
| f.write_joined(&tys[..tys.len() - 1], ", ")?; |
| if *is_varargs { |
| write!(f, "{}...", if tys.len() == 1 { "" } else { ", " })?; |
| } |
| write!(f, ")")?; |
| let ret_ty = tys.last().unwrap(); |
| match ret_ty { |
| TypeRef::Tuple(tup) if tup.is_empty() => {} |
| _ => { |
| write!(f, " -> ")?; |
| ret_ty.hir_fmt(f)?; |
| } |
| } |
| } |
| TypeRef::ImplTrait(bounds) => { |
| write!(f, "impl ")?; |
| f.write_joined(bounds, " + ")?; |
| } |
| TypeRef::DynTrait(bounds) => { |
| write!(f, "dyn ")?; |
| f.write_joined(bounds, " + ")?; |
| } |
| TypeRef::Macro(macro_call) => { |
| let macro_call = macro_call.to_node(f.db.upcast()); |
| let ctx = body::LowerCtx::with_hygiene(f.db.upcast(), &Hygiene::new_unhygienic()); |
| match macro_call.path() { |
| Some(path) => match Path::from_src(path, &ctx) { |
| Some(path) => path.hir_fmt(f)?, |
| None => write!(f, "{{macro}}")?, |
| }, |
| None => write!(f, "{{macro}}")?, |
| } |
| write!(f, "!(..)")?; |
| } |
| TypeRef::Error => write!(f, "{{error}}")?, |
| } |
| Ok(()) |
| } |
| } |
| |
| impl HirDisplay for TypeBound { |
| fn hir_fmt(&self, f: &mut HirFormatter) -> Result<(), HirDisplayError> { |
| match self { |
| TypeBound::Path(path, modifier) => { |
| match modifier { |
| TraitBoundModifier::None => (), |
| TraitBoundModifier::Maybe => write!(f, "?")?, |
| } |
| path.hir_fmt(f) |
| } |
| TypeBound::Lifetime(lifetime) => write!(f, "{}", lifetime.name), |
| TypeBound::ForLifetime(lifetimes, path) => { |
| write!(f, "for<{}> ", lifetimes.iter().format(", "))?; |
| path.hir_fmt(f) |
| } |
| TypeBound::Error => write!(f, "{{error}}"), |
| } |
| } |
| } |
| |
| impl HirDisplay for Path { |
| fn hir_fmt(&self, f: &mut HirFormatter) -> Result<(), HirDisplayError> { |
| match (self.type_anchor(), self.kind()) { |
| (Some(anchor), _) => { |
| write!(f, "<")?; |
| anchor.hir_fmt(f)?; |
| write!(f, ">")?; |
| } |
| (_, PathKind::Plain) => {} |
| (_, PathKind::Abs) => {} |
| (_, PathKind::Crate) => write!(f, "crate")?, |
| (_, PathKind::Super(0)) => write!(f, "self")?, |
| (_, PathKind::Super(n)) => { |
| for i in 0..*n { |
| if i > 0 { |
| write!(f, "::")?; |
| } |
| write!(f, "super")?; |
| } |
| } |
| (_, PathKind::DollarCrate(_)) => write!(f, "{{extern_crate}}")?, |
| } |
| |
| for (seg_idx, segment) in self.segments().iter().enumerate() { |
| if !matches!(self.kind(), PathKind::Plain) || seg_idx > 0 { |
| write!(f, "::")?; |
| } |
| write!(f, "{}", segment.name)?; |
| if let Some(generic_args) = segment.args_and_bindings { |
| // We should be in type context, so format as `Foo<Bar>` instead of `Foo::<Bar>`. |
| // Do we actually format expressions? |
| if generic_args.desugared_from_fn { |
| // First argument will be a tuple, which already includes the parentheses. |
| // If the tuple only contains 1 item, write it manually to avoid the trailing `,`. |
| if let hir_def::path::GenericArg::Type(TypeRef::Tuple(v)) = |
| &generic_args.args[0] |
| { |
| if v.len() == 1 { |
| write!(f, "(")?; |
| v[0].hir_fmt(f)?; |
| write!(f, ")")?; |
| } else { |
| generic_args.args[0].hir_fmt(f)?; |
| } |
| } |
| if let Some(ret) = &generic_args.bindings[0].type_ref { |
| if !matches!(ret, TypeRef::Tuple(v) if v.is_empty()) { |
| write!(f, " -> ")?; |
| ret.hir_fmt(f)?; |
| } |
| } |
| return Ok(()); |
| } |
| |
| write!(f, "<")?; |
| let mut first = true; |
| for arg in &generic_args.args { |
| if first { |
| first = false; |
| if generic_args.has_self_type { |
| // FIXME: Convert to `<Ty as Trait>` form. |
| write!(f, "Self = ")?; |
| } |
| } else { |
| write!(f, ", ")?; |
| } |
| arg.hir_fmt(f)?; |
| } |
| for binding in &generic_args.bindings { |
| if first { |
| first = false; |
| } else { |
| write!(f, ", ")?; |
| } |
| write!(f, "{}", binding.name)?; |
| match &binding.type_ref { |
| Some(ty) => { |
| write!(f, " = ")?; |
| ty.hir_fmt(f)? |
| } |
| None => { |
| write!(f, ": ")?; |
| f.write_joined(&binding.bounds, " + ")?; |
| } |
| } |
| } |
| write!(f, ">")?; |
| } |
| } |
| Ok(()) |
| } |
| } |
| |
| impl HirDisplay for hir_def::path::GenericArg { |
| fn hir_fmt(&self, f: &mut HirFormatter) -> Result<(), HirDisplayError> { |
| match self { |
| hir_def::path::GenericArg::Type(ty) => ty.hir_fmt(f), |
| hir_def::path::GenericArg::Lifetime(lifetime) => write!(f, "{}", lifetime.name), |
| } |
| } |
| } |
