bjoernager/rust
bjoernager/rust
1
Fork 0
Code Activity

Handle multi diagnostics

Browse source
This commit is contained in:
Roxane 2021-07-08 17:04:58 -04:00
parent 59f634bc2d
commit ca44372957
7 changed files with 625 additions and 185 deletions
Download patch file Download diff file Expand all files Collapse all files

354
compiler/rustc_typeck/src/check/upvar.rs
View file

@ -50,6 +50,7 @@ use rustc_span::sym;
use rustc_span::{MultiSpan, Span, Symbol};
use rustc_trait_selection::infer::InferCtxtExt;
use rustc_data_structures::stable_map::FxHashMap;
use rustc_data_structures::stable_set::FxHashSet;
use rustc_index::vec::Idx;
use rustc_target::abi::VariantIdx;
@ -81,6 +82,22 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
}
}
/// Intermediate format to store the hir_id pointing to the use that resulted in the
/// corresponding place being captured and a String which contains the captured value's
/// name (i.e: a.b.c)
type CapturesInfo = (Option<hir::HirId>, String);
/// Intermediate format to store information needed to generate migration lint. The tuple
/// contains the hir_id pointing to the use that resulted in the
/// corresponding place being captured, a String which contains the captured value's
/// name (i.e: a.b.c) and a String which contains the reason why migration is needed for that
/// capture
type MigrationNeededForCapture = (Option<hir::HirId>, String, String);
/// Intermediate format to store the hir id of the root variable and a HashSet containing
/// information on why the root variable should be fully captured
type MigrationDiagnosticInfo = (hir::HirId, FxHashSet<MigrationNeededForCapture>);
struct InferBorrowKindVisitor<'a, 'tcx> {
fcx: &'a FnCtxt<'a, 'tcx>,
}
@ -513,45 +530,41 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
.as_str(),
);
for (var_hir_id, diagnostics_info) in need_migrations.iter() {
let mut captured_names = format!("");
// Label every Span which are responsible for the captured values
for (captured_hir_id, captured_name) in diagnostics_info.iter() {
// Labels all the usage of the captured variable and why they are responsible
// for migration being needed
for (captured_hir_id, captured_name, reasons) in diagnostics_info.iter() {
if let Some(captured_hir_id) = captured_hir_id {
let cause_span = self.tcx.hir().span(*captured_hir_id);
diagnostics_builder.span_label(cause_span, format!("in Rust 2018, closure captures all of `{}`, but in Rust 2021, it only captures `{}`",
self.tcx.hir().name(*var_hir_id),
captured_name,
));
if captured_names == "" {
captured_names = format!("`{}`", captured_name);
} else {
captured_names = format!("{}, `{}`", captured_names, captured_name);
}
}
}
// Add a label pointing to where a closure and it's captured variables affected by drop order are dropped
if reasons.contains("drop order") {
let drop_location_span = drop_location_span(self.tcx, &closure_hir_id);
// Add a label pointing to where a captured variable affected by drop order
// is dropped
if reasons.contains("drop order") {
let drop_location_span = drop_location_span(self.tcx, &closure_hir_id);
diagnostics_builder.span_label(drop_location_span, format!("in Rust 2018, `{}` would be dropped here, but in Rust 2021, only {} would be dropped here alongside the closure",
self.tcx.hir().name(*var_hir_id),
captured_names,
));
}
diagnostics_builder.span_label(drop_location_span, format!("in Rust 2018, `{}` would be dropped here, but in Rust 2021, only `{}` would be dropped here alongside the closure",
self.tcx.hir().name(*var_hir_id),
captured_name,
));
}
// Add a label explaining why a closure no longer implements a trait
if reasons.contains("trait implementation") {
let missing_trait = &reasons[..reasons.find("trait implementation").unwrap() - 1];
// Add a label explaining why a closure no longer implements a trait
if reasons.contains("trait implementation") {
let missing_trait = &reasons[..reasons.find("trait implementation").unwrap() - 1];
diagnostics_builder.span_label(closure_head_span, format!("in Rust 2018, this closure would implement {} as `{}` implements {}, but in Rust 2021, this closure would no longer implement {} as {} does not implement {}",
missing_trait,
self.tcx.hir().name(*var_hir_id),
missing_trait,
missing_trait,
captured_names,
missing_trait,
));
diagnostics_builder.span_label(closure_head_span, format!("in Rust 2018, this closure would implement {} as `{}` implements {}, but in Rust 2021, this closure would no longer implement {} as `{}` does not implement {}",
missing_trait,
self.tcx.hir().name(*var_hir_id),
missing_trait,
missing_trait,
captured_name,
missing_trait,
));
}
}
}
diagnostics_builder.note("for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/disjoint-capture-in-closures.html>");
@ -616,16 +629,29 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
reasons
}
/// Returns a tuple that contains the hir_id pointing to the use that resulted in the
/// corresponding place being captured and a String which contains the captured value's name
/// (i.e: a.b.c) if migration is needed for trait for the provided var_hir_id, otherwise returns None
fn need_2229_migrations_for_trait(
/// Figures out the list of root variables (and their types) that aren't completely
/// captured by the closure when `capture_disjoint_fields` is enabled and auto-traits
/// differ between the root variable and the captured paths.
///
/// Returns a tuple containing a HashMap of CapturesInfo that maps to a HashSet of trait names
/// if migration is needed for traits for the provided var_hir_id, otherwise returns None
fn compute_2229_migrations_for_trait(
&self,
min_captures: Option<&ty::RootVariableMinCaptureList<'tcx>>,
var_hir_id: hir::HirId,
check_trait: Option<DefId>,
closure_clause: hir::CaptureBy,
) -> Option<(Option<hir::HirId>, String)> {
) -> Option<FxHashMap<CapturesInfo, FxHashSet<&str>>> {
let auto_traits_def_id = vec![
self.tcx.lang_items().clone_trait(),
self.tcx.lang_items().sync_trait(),
self.tcx.get_diagnostic_item(sym::send_trait),
self.tcx.lang_items().unpin_trait(),
self.tcx.get_diagnostic_item(sym::unwind_safe_trait),
self.tcx.get_diagnostic_item(sym::ref_unwind_safe_trait),
];
let auto_traits =
vec!["`Clone`", "`Sync`", "`Send`", "`Unpin`", "`UnwindSafe`", "`RefUnwindSafe`"];
let root_var_min_capture_list = if let Some(root_var_min_capture_list) =
min_captures.and_then(|m| m.get(&var_hir_id))
{
@ -650,19 +676,26 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
}
};
let obligation_should_hold = check_trait
.map(|check_trait| {
self.infcx
.type_implements_trait(
check_trait,
ty,
self.tcx.mk_substs_trait(ty, &[]),
self.param_env,
)
.must_apply_modulo_regions()
})
.unwrap_or(false);
let mut obligations_should_hold = Vec::new();
// Checks if a root variable implements any of the auto traits
for check_trait in auto_traits_def_id.iter() {
obligations_should_hold.push(
check_trait
.map(|check_trait| {
self.infcx
.type_implements_trait(
check_trait,
ty,
self.tcx.mk_substs_trait(ty, &[]),
self.param_env,
)
.must_apply_modulo_regions()
})
.unwrap_or(false),
);
}
let mut problematic_captures = FxHashMap::default();
// Check whether captured fields also implement the trait
for capture in root_var_min_capture_list.iter() {
let ty = apply_capture_kind_on_capture_ty(
@ -671,114 +704,48 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
capture.info.capture_kind,
);
let obligation_holds_for_capture = check_trait
.map(|check_trait| {
self.infcx
.type_implements_trait(
check_trait,
ty,
self.tcx.mk_substs_trait(ty, &[]),
self.param_env,
)
.must_apply_modulo_regions()
})
.unwrap_or(false);
// Checks if a capture implements any of the auto traits
let mut obligations_holds_for_capture = Vec::new();
for check_trait in auto_traits_def_id.iter() {
obligations_holds_for_capture.push(
check_trait
.map(|check_trait| {
self.infcx
.type_implements_trait(
check_trait,
ty,
self.tcx.mk_substs_trait(ty, &[]),
self.param_env,
)
.must_apply_modulo_regions()
})
.unwrap_or(false),
);
}
if !obligation_holds_for_capture && obligation_should_hold {
return Some((capture.info.path_expr_id, capture.to_string(self.tcx)));
let mut capture_problems = FxHashSet::default();
// Checks if for any of the auto traits, one or more trait is implemented
// by the root variable but not by the capture
for (idx, _) in obligations_should_hold.iter().enumerate() {
if !obligations_holds_for_capture[idx] && obligations_should_hold[idx] {
capture_problems.insert(auto_traits[idx]);
}
}
if capture_problems.len() > 0 {
problematic_captures.insert(
(capture.info.path_expr_id, capture.to_string(self.tcx)),
capture_problems,
);
}
}
if problematic_captures.len() > 0 {
return Some(problematic_captures);
}
None
}
/// Figures out the list of root variables (and their types) that aren't completely
/// captured by the closure when `capture_disjoint_fields` is enabled and auto-traits
/// differ between the root variable and the captured paths.
///
/// Returns a tuple containing a HashSet of traits that not implemented by the captured fields
/// of a root variables that has the provided var_hir_id and a HashSet of tuples that contains
/// the hir_id pointing to the use that resulted in the corresponding place being captured and
/// a String which contains the captured value's name (i.e: a.b.c) if migration is needed for
/// trait for the provided var_hir_id, otherwise returns None
fn compute_2229_migrations_for_trait(
&self,
min_captures: Option<&ty::RootVariableMinCaptureList<'tcx>>,
var_hir_id: hir::HirId,
closure_clause: hir::CaptureBy,
) -> Option<(FxHashSet<&str>, FxHashSet<(Option<hir::HirId>, String)>)> {
let tcx = self.infcx.tcx;
// Check whether catpured fields also implement the trait
let mut auto_trait_reasons = FxHashSet::default();
let mut diagnostics_info = FxHashSet::default();
if let Some(info) = self.need_2229_migrations_for_trait(
min_captures,
var_hir_id,
tcx.lang_items().clone_trait(),
closure_clause,
) {
auto_trait_reasons.insert("`Clone`");
diagnostics_info.insert(info);
}
if let Some(info) = self.need_2229_migrations_for_trait(
min_captures,
var_hir_id,
tcx.lang_items().sync_trait(),
closure_clause,
) {
auto_trait_reasons.insert("`Sync`");
diagnostics_info.insert(info);
}
if let Some(info) = self.need_2229_migrations_for_trait(
min_captures,
var_hir_id,
tcx.get_diagnostic_item(sym::send_trait),
closure_clause,
) {
auto_trait_reasons.insert("`Send`");
diagnostics_info.insert(info);
}
if let Some(info) = self.need_2229_migrations_for_trait(
min_captures,
var_hir_id,
tcx.lang_items().unpin_trait(),
closure_clause,
) {
auto_trait_reasons.insert("`Unpin`");
diagnostics_info.insert(info);
}
if let Some(info) = self.need_2229_migrations_for_trait(
min_captures,
var_hir_id,
tcx.get_diagnostic_item(sym::unwind_safe_trait),
closure_clause,
) {
auto_trait_reasons.insert("`UnwindSafe`");
diagnostics_info.insert(info);
}
if let Some(info) = self.need_2229_migrations_for_trait(
min_captures,
var_hir_id,
tcx.get_diagnostic_item(sym::ref_unwind_safe_trait),
closure_clause,
) {
auto_trait_reasons.insert("`RefUnwindSafe`");
diagnostics_info.insert(info);
}
if auto_trait_reasons.len() > 0 {
return Some((auto_trait_reasons, diagnostics_info));
}
return None;
}
/// Figures out the list of root variables (and their types) that aren't completely
/// captured by the closure when `capture_disjoint_fields` is enabled and drop order of
/// some path starting at that root variable **might** be affected.
@ -789,9 +756,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
/// - It wasn't completely captured by the closure, **and**
/// - One of the paths starting at this root variable, that is not captured needs Drop.
///
/// This function only returns a HashSet of tuples for significant drops. The returned HashSet
/// of tuples contains the hir_id pointing to the use that resulted in the corresponding place
/// being captured anda String which contains the captured value's name (i.e: a.b.c)
/// This function only returns a HashSet of CapturesInfo for significant drops. If there
/// are no significant drops than None is returned
fn compute_2229_migrations_for_drop(
&self,
closure_def_id: DefId,
@ -799,7 +765,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
min_captures: Option<&ty::RootVariableMinCaptureList<'tcx>>,
closure_clause: hir::CaptureBy,
var_hir_id: hir::HirId,
) -> Option<FxHashSet<(Option<hir::HirId>, String)>> {
) -> Option<FxHashSet<CapturesInfo>> {
let ty = self.infcx.resolve_vars_if_possible(self.node_ty(var_hir_id));
if !ty.has_significant_drop(self.tcx, self.tcx.param_env(closure_def_id.expect_local())) {
@ -873,17 +839,16 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
/// - One of the paths captured does not implement all the auto-traits its root variable
/// implements.
///
/// Returns a tuple containing a vector of tuples of HirIds and a HashSet of tuples that contains
/// the hir_id pointing to the use that resulted in the corresponding place being captured and
/// a String which contains the captured value's name (i.e: a.b.c), as well as a String
/// Returns a tuple containing a vector of MigrationDiagnosticInfo, as well as a String
/// containing the reason why root variables whose HirId is contained in the vector should
/// be captured
fn compute_2229_migrations(
&self,
closure_def_id: DefId,
closure_span: Span,
closure_clause: hir::CaptureBy,
min_captures: Option<&ty::RootVariableMinCaptureList<'tcx>>,
) -> (Vec<(hir::HirId, FxHashSet<(Option<hir::HirId>, String)>)>, String) {
) -> (Vec<MigrationDiagnosticInfo>, String) {
let upvars = if let Some(upvars) = self.tcx.upvars_mentioned(closure_def_id) {
upvars
} else {
@ -891,42 +856,77 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
};
let mut need_migrations = Vec::new();
let mut auto_trait_reasons = FxHashSet::default();
let mut drop_reorder_reason = false;
let mut auto_trait_migration_reasons = FxHashSet::default();
let mut drop_migration_needed = false;
// Perform auto-trait analysis
for (&var_hir_id, _) in upvars.iter() {
let mut need_migration = false;
let mut responsible_captured_hir_ids = FxHashSet::default();
if let Some((trait_migration_cause, diagnostics_info)) =
let auto_trait_diagnostic = if let Some(diagnostics_info) =
self.compute_2229_migrations_for_trait(min_captures, var_hir_id, closure_clause)
{
need_migration = true;
auto_trait_reasons.extend(trait_migration_cause);
responsible_captured_hir_ids.extend(diagnostics_info);
diagnostics_info
} else {
FxHashMap::default()
};
let drop_reorder_diagnostic = if let Some(diagnostics_info) = self
.compute_2229_migrations_for_drop(
closure_def_id,
closure_span,
min_captures,
closure_clause,
var_hir_id,
) {
drop_migration_needed = true;
diagnostics_info
} else {
FxHashSet::default()
};
// Combine all the captures responsible for needing migrations into one HashSet
let mut capture_disagnostic = drop_reorder_diagnostic.clone();
for key in auto_trait_diagnostic.keys() {
capture_disagnostic.insert(key.clone());
}
if let Some(diagnostics_info) = self.compute_2229_migrations_for_drop(
closure_def_id,
closure_span,
min_captures,
closure_clause,
var_hir_id,
) {
need_migration = true;
drop_reorder_reason = true;
responsible_captured_hir_ids.extend(diagnostics_info);
for captured_info in capture_disagnostic.iter() {
// Get the auto trait reasons of why migration is needed because of that capture, if there are any
let capture_trait_reasons =
if let Some(reasons) = auto_trait_diagnostic.get(captured_info) {
reasons.clone()
} else {
FxHashSet::default()
};
// Check if migration is needed because of drop reorder as a result of that capture
let capture_drop_reorder_reason = drop_reorder_diagnostic.contains(captured_info);
// Combine all the reasons of why the root variable should be captured as a result of
// auto trait implementation issues
auto_trait_migration_reasons.extend(capture_trait_reasons.clone());
responsible_captured_hir_ids.insert((
captured_info.0,
captured_info.1.clone(),
self.compute_2229_migrations_reasons(
capture_trait_reasons,
capture_drop_reorder_reason,
),
));
}
if need_migration {
if capture_disagnostic.len() > 0 {
need_migrations.push((var_hir_id, responsible_captured_hir_ids));
}
}
(
need_migrations,
self.compute_2229_migrations_reasons(auto_trait_reasons, drop_reorder_reason),
self.compute_2229_migrations_reasons(
auto_trait_migration_reasons,
drop_migration_needed,
),
)
}
@ -1964,7 +1964,7 @@ fn should_do_rust_2021_incompatible_closure_captures_analysis(
/// - s2: Comma separated names of the variables being migrated.
fn migration_suggestion_for_2229(
tcx: TyCtxt<'_>,
need_migrations: &Vec<(hir::HirId, FxHashSet<(Option<hir::HirId>, String)>)>,
need_migrations: &Vec<MigrationDiagnosticInfo>,
) -> (String, String) {
let need_migrations_variables =
need_migrations.iter().map(|(v, _)| var_name(tcx, *v)).collect::<Vec<_>>();