minor: make code clearer with ControlFlow

This commit is contained in:
Aleksey Kladov 2021-09-11 20:49:10 +03:00
parent abdb75912c
commit 9b2bac621e
3 changed files with 71 additions and 73 deletions

View File

@ -31,7 +31,7 @@
mod display;
use std::{iter, sync::Arc};
use std::{iter, ops::ControlFlow, sync::Arc};
use arrayvec::ArrayVec;
use base_db::{CrateDisplayName, CrateId, Edition, FileId};
@ -2573,12 +2573,14 @@ pub fn iterate_method_candidates<T>(
krate,
traits_in_scope,
name,
&mut |ty, assoc_item_id| match assoc_item_id {
AssocItemId::FunctionId(it) => {
slot = callback(self.derived(ty.clone()), it.into());
slot.is_some()
&mut |ty, assoc_item_id| {
if let AssocItemId::FunctionId(func) = assoc_item_id {
if let Some(res) = callback(self.derived(ty.clone()), func.into()) {
slot = Some(res);
return ControlFlow::Break(());
}
AssocItemId::ConstId(_) | AssocItemId::TypeAliasId(_) => false,
}
ControlFlow::Continue(())
},
);
slot
@ -2590,7 +2592,7 @@ fn iterate_method_candidates_dyn(
krate: Crate,
traits_in_scope: &FxHashSet<TraitId>,
name: Option<&Name>,
callback: &mut dyn FnMut(&Ty, AssocItemId) -> bool,
callback: &mut dyn FnMut(&Ty, AssocItemId) -> ControlFlow<()>,
) {
// There should be no inference vars in types passed here
// FIXME check that?
@ -2630,8 +2632,11 @@ pub fn iterate_path_candidates<T>(
traits_in_scope,
name,
&mut |ty, assoc_item_id| {
slot = callback(self.derived(ty.clone()), assoc_item_id.into());
slot.is_some()
if let Some(res) = callback(self.derived(ty.clone()), assoc_item_id.into()) {
slot = Some(res);
return ControlFlow::Break(());
}
ControlFlow::Continue(())
},
);
slot
@ -2643,7 +2648,7 @@ fn iterate_path_candidates_dyn(
krate: Crate,
traits_in_scope: &FxHashSet<TraitId>,
name: Option<&Name>,
callback: &mut dyn FnMut(&Ty, AssocItemId) -> bool,
callback: &mut dyn FnMut(&Ty, AssocItemId) -> ControlFlow<()>,
) {
let canonical = hir_ty::replace_errors_with_variables(&self.ty);

View File

@ -2,7 +2,7 @@
//! For details about how this works in rustc, see the method lookup page in the
//! [rustc guide](https://rust-lang.github.io/rustc-guide/method-lookup.html)
//! and the corresponding code mostly in librustc_typeck/check/method/probe.rs.
use std::{iter, sync::Arc};
use std::{iter, ops::ControlFlow, sync::Arc};
use arrayvec::ArrayVec;
use base_db::{CrateId, Edition};
@ -435,8 +435,11 @@ pub fn iterate_method_candidates<T>(
mode,
&mut |ty, item| {
assert!(slot.is_none());
slot = callback(ty, item);
slot.is_some()
if let Some(it) = callback(ty, item) {
slot = Some(it);
return ControlFlow::Break(());
}
ControlFlow::Continue(())
},
);
slot
@ -451,8 +454,8 @@ pub fn iterate_method_candidates_dyn(
visible_from_module: Option<ModuleId>,
name: Option<&Name>,
mode: LookupMode,
callback: &mut dyn FnMut(&Ty, AssocItemId) -> bool,
) -> bool {
callback: &mut dyn FnMut(&Ty, AssocItemId) -> ControlFlow<()>,
) -> ControlFlow<()> {
match mode {
LookupMode::MethodCall => {
// For method calls, rust first does any number of autoderef, and then one
@ -480,7 +483,7 @@ pub fn iterate_method_candidates_dyn(
let deref_chain = autoderef_method_receiver(db, krate, ty);
for i in 0..deref_chain.len() {
if iterate_method_candidates_with_autoref(
iterate_method_candidates_with_autoref(
&deref_chain[i..],
db,
env.clone(),
@ -489,11 +492,9 @@ pub fn iterate_method_candidates_dyn(
visible_from_module,
name,
callback,
) {
return true;
)?;
}
}
false
ControlFlow::Continue(())
}
LookupMode::Path => {
// No autoderef for path lookups
@ -519,9 +520,9 @@ fn iterate_method_candidates_with_autoref(
traits_in_scope: &FxHashSet<TraitId>,
visible_from_module: Option<ModuleId>,
name: Option<&Name>,
mut callback: &mut dyn FnMut(&Ty, AssocItemId) -> bool,
) -> bool {
if iterate_method_candidates_by_receiver(
mut callback: &mut dyn FnMut(&Ty, AssocItemId) -> ControlFlow<()>,
) -> ControlFlow<()> {
iterate_method_candidates_by_receiver(
&deref_chain[0],
&deref_chain[1..],
db,
@ -531,15 +532,15 @@ fn iterate_method_candidates_with_autoref(
visible_from_module,
name,
&mut callback,
) {
return true;
}
)?;
let refed = Canonical {
binders: deref_chain[0].binders.clone(),
value: TyKind::Ref(Mutability::Not, static_lifetime(), deref_chain[0].value.clone())
.intern(&Interner),
};
if iterate_method_candidates_by_receiver(
iterate_method_candidates_by_receiver(
&refed,
deref_chain,
db,
@ -549,15 +550,15 @@ fn iterate_method_candidates_with_autoref(
visible_from_module,
name,
&mut callback,
) {
return true;
}
)?;
let ref_muted = Canonical {
binders: deref_chain[0].binders.clone(),
value: TyKind::Ref(Mutability::Mut, static_lifetime(), deref_chain[0].value.clone())
.intern(&Interner),
};
if iterate_method_candidates_by_receiver(
iterate_method_candidates_by_receiver(
&ref_muted,
deref_chain,
db,
@ -567,10 +568,7 @@ fn iterate_method_candidates_with_autoref(
visible_from_module,
name,
&mut callback,
) {
return true;
}
false
)
}
fn iterate_method_candidates_by_receiver(
@ -582,13 +580,13 @@ fn iterate_method_candidates_by_receiver(
traits_in_scope: &FxHashSet<TraitId>,
visible_from_module: Option<ModuleId>,
name: Option<&Name>,
mut callback: &mut dyn FnMut(&Ty, AssocItemId) -> bool,
) -> bool {
mut callback: &mut dyn FnMut(&Ty, AssocItemId) -> ControlFlow<()>,
) -> ControlFlow<()> {
// We're looking for methods with *receiver* type receiver_ty. These could
// be found in any of the derefs of receiver_ty, so we have to go through
// that.
for self_ty in std::iter::once(receiver_ty).chain(rest_of_deref_chain) {
if iterate_inherent_methods(
iterate_inherent_methods(
self_ty,
db,
env.clone(),
@ -597,12 +595,11 @@ fn iterate_method_candidates_by_receiver(
krate,
visible_from_module,
&mut callback,
) {
return true;
}
)?
}
for self_ty in std::iter::once(receiver_ty).chain(rest_of_deref_chain) {
if iterate_trait_method_candidates(
iterate_trait_method_candidates(
self_ty,
db,
env.clone(),
@ -611,11 +608,10 @@ fn iterate_method_candidates_by_receiver(
name,
Some(receiver_ty),
&mut callback,
) {
return true;
)?
}
}
false
ControlFlow::Continue(())
}
fn iterate_method_candidates_for_self_ty(
@ -626,9 +622,9 @@ fn iterate_method_candidates_for_self_ty(
traits_in_scope: &FxHashSet<TraitId>,
visible_from_module: Option<ModuleId>,
name: Option<&Name>,
mut callback: &mut dyn FnMut(&Ty, AssocItemId) -> bool,
) -> bool {
if iterate_inherent_methods(
mut callback: &mut dyn FnMut(&Ty, AssocItemId) -> ControlFlow<()>,
) -> ControlFlow<()> {
iterate_inherent_methods(
self_ty,
db,
env.clone(),
@ -637,9 +633,7 @@ fn iterate_method_candidates_for_self_ty(
krate,
visible_from_module,
&mut callback,
) {
return true;
}
)?;
iterate_trait_method_candidates(self_ty, db, env, krate, traits_in_scope, name, None, callback)
}
@ -651,22 +645,24 @@ fn iterate_trait_method_candidates(
traits_in_scope: &FxHashSet<TraitId>,
name: Option<&Name>,
receiver_ty: Option<&Canonical<Ty>>,
callback: &mut dyn FnMut(&Ty, AssocItemId) -> bool,
) -> bool {
callback: &mut dyn FnMut(&Ty, AssocItemId) -> ControlFlow<()>,
) -> ControlFlow<()> {
let receiver_is_array = matches!(self_ty.value.kind(&Interner), chalk_ir::TyKind::Array(..));
// if ty is `dyn Trait`, the trait doesn't need to be in scope
let inherent_trait =
self_ty.value.dyn_trait().into_iter().flat_map(|t| all_super_traits(db.upcast(), t));
let env_traits = if let TyKind::Placeholder(_) = self_ty.value.kind(&Interner) {
let env_traits = match self_ty.value.kind(&Interner) {
TyKind::Placeholder(_) => {
// if we have `T: Trait` in the param env, the trait doesn't need to be in scope
env.traits_in_scope_from_clauses(&self_ty.value)
.flat_map(|t| all_super_traits(db.upcast(), t))
.collect()
} else {
Vec::new()
}
_ => Vec::new(),
};
let traits =
inherent_trait.chain(env_traits.into_iter()).chain(traits_in_scope.iter().copied());
'traits: for t in traits {
let data = db.trait_data(t);
@ -701,12 +697,10 @@ fn iterate_trait_method_candidates(
}
known_implemented = true;
// FIXME: we shouldn't be ignoring the binders here
if callback(&self_ty.value, *item) {
return true;
callback(&self_ty.value, *item)?
}
}
}
false
ControlFlow::Continue(())
}
fn filter_inherent_impls_for_self_ty<'i>(
@ -744,12 +738,13 @@ fn iterate_inherent_methods(
receiver_ty: Option<&Canonical<Ty>>,
krate: CrateId,
visible_from_module: Option<ModuleId>,
callback: &mut dyn FnMut(&Ty, AssocItemId) -> bool,
) -> bool {
callback: &mut dyn FnMut(&Ty, AssocItemId) -> ControlFlow<()>,
) -> ControlFlow<()> {
let def_crates = match def_crates(db, &self_ty.value, krate) {
Some(k) => k,
None => return false,
None => return ControlFlow::Continue(()),
};
for krate in def_crates {
let impls = db.inherent_impls_in_crate(krate);
@ -779,13 +774,11 @@ fn iterate_inherent_methods(
continue;
}
let receiver_ty = receiver_ty.map(|x| &x.value).unwrap_or(&self_ty.value);
if callback(receiver_ty, item) {
return true;
callback(receiver_ty, item)?;
}
}
}
}
false
ControlFlow::Continue(())
}
/// Returns the self type for the index trait call.

View File

@ -8,7 +8,7 @@
use crate::flags;
// Latest stable, feel free to send a PR if this lags behind.
const REQUIRED_RUST_VERSION: u32 = 53;
const REQUIRED_RUST_VERSION: u32 = 55;
impl flags::Install {
pub(crate) fn run(self) -> Result<()> {