873 lines
35 KiB
Rust
873 lines
35 KiB
Rust
use std::cmp::Reverse;
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use errors::{Applicability, DiagnosticBuilder, DiagnosticId};
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use log::debug;
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use rustc::hir::def::{self, DefKind, CtorKind, Namespace::*};
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use rustc::hir::def_id::{CRATE_DEF_INDEX, DefId};
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use rustc::session::{Session, config::nightly_options};
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use syntax::ast::{self, Expr, ExprKind, Ident};
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use syntax::ext::base::MacroKind;
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use syntax::symbol::{Symbol, kw};
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use syntax_pos::{BytePos, Span};
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type Res = def::Res<ast::NodeId>;
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use crate::macros::ParentScope;
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use crate::resolve_imports::{ImportDirective, ImportDirectiveSubclass, ImportResolver};
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use crate::{import_candidate_to_enum_paths, is_self_type, is_self_value, path_names_to_string};
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use crate::{AssocSuggestion, CrateLint, ImportSuggestion, ModuleOrUniformRoot, PathResult,
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PathSource, Resolver, Segment, Suggestion};
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impl<'a> Resolver<'a> {
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/// Handles error reporting for `smart_resolve_path_fragment` function.
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/// Creates base error and amends it with one short label and possibly some longer helps/notes.
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pub(crate) fn smart_resolve_report_errors(
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&mut self,
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path: &[Segment],
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span: Span,
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source: PathSource<'_>,
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res: Option<Res>,
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) -> (DiagnosticBuilder<'a>, Vec<ImportSuggestion>) {
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let ident_span = path.last().map_or(span, |ident| ident.ident.span);
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let ns = source.namespace();
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let is_expected = &|res| source.is_expected(res);
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let is_enum_variant = &|res| {
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if let Res::Def(DefKind::Variant, _) = res { true } else { false }
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};
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// Make the base error.
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let expected = source.descr_expected();
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let path_str = Segment::names_to_string(path);
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let item_str = path.last().unwrap().ident;
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let code = source.error_code(res.is_some());
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let (base_msg, fallback_label, base_span) = if let Some(res) = res {
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(format!("expected {}, found {} `{}`", expected, res.descr(), path_str),
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format!("not a {}", expected),
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span)
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} else {
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let item_span = path.last().unwrap().ident.span;
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let (mod_prefix, mod_str) = if path.len() == 1 {
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(String::new(), "this scope".to_string())
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} else if path.len() == 2 && path[0].ident.name == kw::PathRoot {
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(String::new(), "the crate root".to_string())
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} else {
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let mod_path = &path[..path.len() - 1];
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let mod_prefix = match self.resolve_path_without_parent_scope(
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mod_path, Some(TypeNS), false, span, CrateLint::No
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) {
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PathResult::Module(ModuleOrUniformRoot::Module(module)) =>
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module.def_kind(),
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_ => None,
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}.map_or(String::new(), |kind| format!("{} ", kind.descr()));
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(mod_prefix, format!("`{}`", Segment::names_to_string(mod_path)))
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};
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(format!("cannot find {} `{}` in {}{}", expected, item_str, mod_prefix, mod_str),
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format!("not found in {}", mod_str),
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item_span)
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};
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let code = DiagnosticId::Error(code.into());
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let mut err = self.session.struct_span_err_with_code(base_span, &base_msg, code);
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// Emit help message for fake-self from other languages (e.g., `this` in Javascript).
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if ["this", "my"].contains(&&*item_str.as_str())
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&& self.self_value_is_available(path[0].ident.span, span) {
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err.span_suggestion(
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span,
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"did you mean",
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"self".to_string(),
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Applicability::MaybeIncorrect,
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);
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}
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// Emit special messages for unresolved `Self` and `self`.
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if is_self_type(path, ns) {
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__diagnostic_used!(E0411);
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err.code(DiagnosticId::Error("E0411".into()));
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err.span_label(span, format!("`Self` is only available in impls, traits, \
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and type definitions"));
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return (err, Vec::new());
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}
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if is_self_value(path, ns) {
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debug!("smart_resolve_path_fragment: E0424, source={:?}", source);
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__diagnostic_used!(E0424);
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err.code(DiagnosticId::Error("E0424".into()));
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err.span_label(span, match source {
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PathSource::Pat => {
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format!("`self` value is a keyword \
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and may not be bound to \
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variables or shadowed")
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}
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_ => {
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format!("`self` value is a keyword \
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only available in methods \
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with `self` parameter")
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}
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});
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return (err, Vec::new());
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}
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// Try to lookup name in more relaxed fashion for better error reporting.
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let ident = path.last().unwrap().ident;
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let candidates = self.lookup_import_candidates(ident, ns, is_expected)
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.drain(..)
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.filter(|ImportSuggestion { did, .. }| {
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match (did, res.and_then(|res| res.opt_def_id())) {
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(Some(suggestion_did), Some(actual_did)) => *suggestion_did != actual_did,
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_ => true,
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}
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})
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.collect::<Vec<_>>();
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let crate_def_id = DefId::local(CRATE_DEF_INDEX);
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if candidates.is_empty() && is_expected(Res::Def(DefKind::Enum, crate_def_id)) {
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let enum_candidates =
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self.lookup_import_candidates(ident, ns, is_enum_variant);
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let mut enum_candidates = enum_candidates.iter()
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.map(|suggestion| {
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import_candidate_to_enum_paths(&suggestion)
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}).collect::<Vec<_>>();
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enum_candidates.sort();
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if !enum_candidates.is_empty() {
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// Contextualize for E0412 "cannot find type", but don't belabor the point
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// (that it's a variant) for E0573 "expected type, found variant".
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let preamble = if res.is_none() {
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let others = match enum_candidates.len() {
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1 => String::new(),
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2 => " and 1 other".to_owned(),
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n => format!(" and {} others", n)
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};
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format!("there is an enum variant `{}`{}; ",
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enum_candidates[0].0, others)
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} else {
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String::new()
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};
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let msg = format!("{}try using the variant's enum", preamble);
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err.span_suggestions(
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span,
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&msg,
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enum_candidates.into_iter()
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.map(|(_variant_path, enum_ty_path)| enum_ty_path)
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// Variants re-exported in prelude doesn't mean `prelude::v1` is the
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// type name!
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// FIXME: is there a more principled way to do this that
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// would work for other re-exports?
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.filter(|enum_ty_path| enum_ty_path != "std::prelude::v1")
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// Also write `Option` rather than `std::prelude::v1::Option`.
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.map(|enum_ty_path| {
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// FIXME #56861: DRY-er prelude filtering.
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enum_ty_path.trim_start_matches("std::prelude::v1::").to_owned()
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}),
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Applicability::MachineApplicable,
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);
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}
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}
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if path.len() == 1 && self.self_type_is_available(span) {
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if let Some(candidate) = self.lookup_assoc_candidate(ident, ns, is_expected) {
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let self_is_available = self.self_value_is_available(path[0].ident.span, span);
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match candidate {
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AssocSuggestion::Field => {
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if self_is_available {
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err.span_suggestion(
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span,
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"you might have meant to use the available field",
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format!("self.{}", path_str),
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Applicability::MachineApplicable,
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);
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} else {
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err.span_label(
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span,
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"a field by this name exists in `Self`",
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);
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}
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}
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AssocSuggestion::MethodWithSelf if self_is_available => {
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err.span_suggestion(
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span,
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"try",
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format!("self.{}", path_str),
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Applicability::MachineApplicable,
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);
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}
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AssocSuggestion::MethodWithSelf | AssocSuggestion::AssocItem => {
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err.span_suggestion(
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span,
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"try",
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format!("Self::{}", path_str),
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Applicability::MachineApplicable,
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);
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}
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}
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return (err, candidates);
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}
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}
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let mut levenshtein_worked = false;
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// Try Levenshtein algorithm.
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let suggestion = self.lookup_typo_candidate(path, ns, is_expected, span);
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if let Some(suggestion) = suggestion {
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let msg = format!(
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"{} {} with a similar name exists",
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suggestion.article, suggestion.kind
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);
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err.span_suggestion(
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ident_span,
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&msg,
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suggestion.candidate.to_string(),
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Applicability::MaybeIncorrect,
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);
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levenshtein_worked = true;
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}
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// Try context-dependent help if relaxed lookup didn't work.
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if let Some(res) = res {
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if self.smart_resolve_context_dependent_help(&mut err,
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span,
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source,
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res,
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&path_str,
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&fallback_label) {
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return (err, candidates);
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}
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}
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// Fallback label.
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if !levenshtein_worked {
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err.span_label(base_span, fallback_label);
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self.type_ascription_suggestion(&mut err, base_span);
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}
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(err, candidates)
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}
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fn followed_by_brace(&self, span: Span) -> (bool, Option<(Span, String)>) {
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// HACK(estebank): find a better way to figure out that this was a
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// parser issue where a struct literal is being used on an expression
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// where a brace being opened means a block is being started. Look
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// ahead for the next text to see if `span` is followed by a `{`.
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let sm = self.session.source_map();
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let mut sp = span;
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loop {
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sp = sm.next_point(sp);
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match sm.span_to_snippet(sp) {
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Ok(ref snippet) => {
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if snippet.chars().any(|c| { !c.is_whitespace() }) {
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break;
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}
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}
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_ => break,
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}
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}
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let followed_by_brace = match sm.span_to_snippet(sp) {
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Ok(ref snippet) if snippet == "{" => true,
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_ => false,
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};
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// In case this could be a struct literal that needs to be surrounded
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// by parenthesis, find the appropriate span.
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let mut i = 0;
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let mut closing_brace = None;
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loop {
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sp = sm.next_point(sp);
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match sm.span_to_snippet(sp) {
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Ok(ref snippet) => {
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if snippet == "}" {
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let sp = span.to(sp);
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if let Ok(snippet) = sm.span_to_snippet(sp) {
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closing_brace = Some((sp, snippet));
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}
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break;
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}
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}
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_ => break,
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}
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i += 1;
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// The bigger the span, the more likely we're incorrect --
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// bound it to 100 chars long.
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if i > 100 {
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break;
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}
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}
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return (followed_by_brace, closing_brace)
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}
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/// Provides context-dependent help for errors reported by the `smart_resolve_path_fragment`
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/// function.
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/// Returns `true` if able to provide context-dependent help.
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fn smart_resolve_context_dependent_help(
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&mut self,
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err: &mut DiagnosticBuilder<'a>,
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span: Span,
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source: PathSource<'_>,
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res: Res,
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path_str: &str,
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fallback_label: &str,
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) -> bool {
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let ns = source.namespace();
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let is_expected = &|res| source.is_expected(res);
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let path_sep = |err: &mut DiagnosticBuilder<'_>, expr: &Expr| match expr.node {
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ExprKind::Field(_, ident) => {
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err.span_suggestion(
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expr.span,
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"use the path separator to refer to an item",
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format!("{}::{}", path_str, ident),
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Applicability::MaybeIncorrect,
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);
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true
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}
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ExprKind::MethodCall(ref segment, ..) => {
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let span = expr.span.with_hi(segment.ident.span.hi());
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err.span_suggestion(
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span,
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"use the path separator to refer to an item",
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format!("{}::{}", path_str, segment.ident),
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Applicability::MaybeIncorrect,
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);
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true
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}
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_ => false,
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};
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let mut bad_struct_syntax_suggestion = || {
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let (followed_by_brace, closing_brace) = self.followed_by_brace(span);
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let mut suggested = false;
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match source {
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PathSource::Expr(Some(parent)) => {
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suggested = path_sep(err, &parent);
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}
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PathSource::Expr(None) if followed_by_brace == true => {
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if let Some((sp, snippet)) = closing_brace {
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err.span_suggestion(
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sp,
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"surround the struct literal with parenthesis",
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format!("({})", snippet),
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Applicability::MaybeIncorrect,
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);
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} else {
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err.span_label(
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span, // Note the parenthesis surrounding the suggestion below
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format!("did you mean `({} {{ /* fields */ }})`?", path_str),
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);
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}
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suggested = true;
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},
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_ => {}
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}
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if !suggested {
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err.span_label(
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span,
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format!("did you mean `{} {{ /* fields */ }}`?", path_str),
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);
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}
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};
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match (res, source) {
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(Res::Def(DefKind::Macro(..), _), _) => {
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err.span_suggestion(
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span,
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"use `!` to invoke the macro",
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format!("{}!", path_str),
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Applicability::MaybeIncorrect,
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);
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if path_str == "try" && span.rust_2015() {
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err.note("if you want the `try` keyword, you need to be in the 2018 edition");
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}
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}
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(Res::Def(DefKind::TyAlias, _), PathSource::Trait(_)) => {
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err.span_label(span, "type aliases cannot be used as traits");
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if nightly_options::is_nightly_build() {
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err.note("did you mean to use a trait alias?");
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}
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}
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(Res::Def(DefKind::Mod, _), PathSource::Expr(Some(parent))) => {
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if !path_sep(err, &parent) {
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return false;
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}
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}
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(Res::Def(DefKind::Enum, def_id), PathSource::TupleStruct)
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| (Res::Def(DefKind::Enum, def_id), PathSource::Expr(..)) => {
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if let Some(variants) = self.collect_enum_variants(def_id) {
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if !variants.is_empty() {
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let msg = if variants.len() == 1 {
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"try using the enum's variant"
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} else {
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"try using one of the enum's variants"
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};
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err.span_suggestions(
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span,
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msg,
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variants.iter().map(path_names_to_string),
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Applicability::MaybeIncorrect,
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);
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}
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} else {
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err.note("did you mean to use one of the enum's variants?");
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}
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},
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(Res::Def(DefKind::Struct, def_id), _) if ns == ValueNS => {
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if let Some((ctor_def, ctor_vis))
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= self.struct_constructors.get(&def_id).cloned() {
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let accessible_ctor = self.is_accessible(ctor_vis);
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if is_expected(ctor_def) && !accessible_ctor {
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err.span_label(
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span,
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format!("constructor is not visible here due to private fields"),
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);
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}
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} else {
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bad_struct_syntax_suggestion();
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}
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}
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(Res::Def(DefKind::Union, _), _) |
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(Res::Def(DefKind::Variant, _), _) |
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(Res::Def(DefKind::Ctor(_, CtorKind::Fictive), _), _) if ns == ValueNS => {
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bad_struct_syntax_suggestion();
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}
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(Res::SelfTy(..), _) if ns == ValueNS => {
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err.span_label(span, fallback_label);
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err.note("can't use `Self` as a constructor, you must use the implemented struct");
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}
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(Res::Def(DefKind::TyAlias, _), _)
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| (Res::Def(DefKind::AssocTy, _), _) if ns == ValueNS => {
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err.note("can't use a type alias as a constructor");
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}
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_ => return false,
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}
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true
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}
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}
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|
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impl<'a, 'b> ImportResolver<'a, 'b> {
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/// Adds suggestions for a path that cannot be resolved.
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pub(crate) fn make_path_suggestion(
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&mut self,
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span: Span,
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mut path: Vec<Segment>,
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parent_scope: &ParentScope<'b>,
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) -> Option<(Vec<Segment>, Vec<String>)> {
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debug!("make_path_suggestion: span={:?} path={:?}", span, path);
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match (path.get(0), path.get(1)) {
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// `{{root}}::ident::...` on both editions.
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// On 2015 `{{root}}` is usually added implicitly.
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(Some(fst), Some(snd)) if fst.ident.name == kw::PathRoot &&
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!snd.ident.is_path_segment_keyword() => {}
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// `ident::...` on 2018.
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(Some(fst), _) if fst.ident.span.rust_2018() &&
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!fst.ident.is_path_segment_keyword() => {
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// Insert a placeholder that's later replaced by `self`/`super`/etc.
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path.insert(0, Segment::from_ident(Ident::invalid()));
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}
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_ => return None,
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}
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self.make_missing_self_suggestion(span, path.clone(), parent_scope)
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.or_else(|| self.make_missing_crate_suggestion(span, path.clone(), parent_scope))
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.or_else(|| self.make_missing_super_suggestion(span, path.clone(), parent_scope))
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.or_else(|| self.make_external_crate_suggestion(span, path, parent_scope))
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}
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/// Suggest a missing `self::` if that resolves to an correct module.
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///
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/// ```
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/// |
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/// LL | use foo::Bar;
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/// | ^^^ did you mean `self::foo`?
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/// ```
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fn make_missing_self_suggestion(
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&mut self,
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span: Span,
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mut path: Vec<Segment>,
|
|
parent_scope: &ParentScope<'b>,
|
|
) -> Option<(Vec<Segment>, Vec<String>)> {
|
|
// Replace first ident with `self` and check if that is valid.
|
|
path[0].ident.name = kw::SelfLower;
|
|
let result = self.resolve_path(&path, None, parent_scope, false, span, CrateLint::No);
|
|
debug!("make_missing_self_suggestion: path={:?} result={:?}", path, result);
|
|
if let PathResult::Module(..) = result {
|
|
Some((path, Vec::new()))
|
|
} else {
|
|
None
|
|
}
|
|
}
|
|
|
|
/// Suggests a missing `crate::` if that resolves to an correct module.
|
|
///
|
|
/// ```
|
|
/// |
|
|
/// LL | use foo::Bar;
|
|
/// | ^^^ did you mean `crate::foo`?
|
|
/// ```
|
|
fn make_missing_crate_suggestion(
|
|
&mut self,
|
|
span: Span,
|
|
mut path: Vec<Segment>,
|
|
parent_scope: &ParentScope<'b>,
|
|
) -> Option<(Vec<Segment>, Vec<String>)> {
|
|
// Replace first ident with `crate` and check if that is valid.
|
|
path[0].ident.name = kw::Crate;
|
|
let result = self.resolve_path(&path, None, parent_scope, false, span, CrateLint::No);
|
|
debug!("make_missing_crate_suggestion: path={:?} result={:?}", path, result);
|
|
if let PathResult::Module(..) = result {
|
|
Some((
|
|
path,
|
|
vec![
|
|
"`use` statements changed in Rust 2018; read more at \
|
|
<https://doc.rust-lang.org/edition-guide/rust-2018/module-system/path-\
|
|
clarity.html>".to_string()
|
|
],
|
|
))
|
|
} else {
|
|
None
|
|
}
|
|
}
|
|
|
|
/// Suggests a missing `super::` if that resolves to an correct module.
|
|
///
|
|
/// ```
|
|
/// |
|
|
/// LL | use foo::Bar;
|
|
/// | ^^^ did you mean `super::foo`?
|
|
/// ```
|
|
fn make_missing_super_suggestion(
|
|
&mut self,
|
|
span: Span,
|
|
mut path: Vec<Segment>,
|
|
parent_scope: &ParentScope<'b>,
|
|
) -> Option<(Vec<Segment>, Vec<String>)> {
|
|
// Replace first ident with `crate` and check if that is valid.
|
|
path[0].ident.name = kw::Super;
|
|
let result = self.resolve_path(&path, None, parent_scope, false, span, CrateLint::No);
|
|
debug!("make_missing_super_suggestion: path={:?} result={:?}", path, result);
|
|
if let PathResult::Module(..) = result {
|
|
Some((path, Vec::new()))
|
|
} else {
|
|
None
|
|
}
|
|
}
|
|
|
|
/// Suggests a missing external crate name if that resolves to an correct module.
|
|
///
|
|
/// ```
|
|
/// |
|
|
/// LL | use foobar::Baz;
|
|
/// | ^^^^^^ did you mean `baz::foobar`?
|
|
/// ```
|
|
///
|
|
/// Used when importing a submodule of an external crate but missing that crate's
|
|
/// name as the first part of path.
|
|
fn make_external_crate_suggestion(
|
|
&mut self,
|
|
span: Span,
|
|
mut path: Vec<Segment>,
|
|
parent_scope: &ParentScope<'b>,
|
|
) -> Option<(Vec<Segment>, Vec<String>)> {
|
|
if path[1].ident.span.rust_2015() {
|
|
return None;
|
|
}
|
|
|
|
// Sort extern crate names in reverse order to get
|
|
// 1) some consistent ordering for emitted dignostics, and
|
|
// 2) `std` suggestions before `core` suggestions.
|
|
let mut extern_crate_names =
|
|
self.resolver.extern_prelude.iter().map(|(ident, _)| ident.name).collect::<Vec<_>>();
|
|
extern_crate_names.sort_by_key(|name| Reverse(name.as_str()));
|
|
|
|
for name in extern_crate_names.into_iter() {
|
|
// Replace first ident with a crate name and check if that is valid.
|
|
path[0].ident.name = name;
|
|
let result = self.resolve_path(&path, None, parent_scope, false, span, CrateLint::No);
|
|
debug!("make_external_crate_suggestion: name={:?} path={:?} result={:?}",
|
|
name, path, result);
|
|
if let PathResult::Module(..) = result {
|
|
return Some((path, Vec::new()));
|
|
}
|
|
}
|
|
|
|
None
|
|
}
|
|
|
|
/// Suggests importing a macro from the root of the crate rather than a module within
|
|
/// the crate.
|
|
///
|
|
/// ```
|
|
/// help: a macro with this name exists at the root of the crate
|
|
/// |
|
|
/// LL | use issue_59764::makro;
|
|
/// | ^^^^^^^^^^^^^^^^^^
|
|
/// |
|
|
/// = note: this could be because a macro annotated with `#[macro_export]` will be exported
|
|
/// at the root of the crate instead of the module where it is defined
|
|
/// ```
|
|
pub(crate) fn check_for_module_export_macro(
|
|
&self,
|
|
directive: &'b ImportDirective<'b>,
|
|
module: ModuleOrUniformRoot<'b>,
|
|
ident: Ident,
|
|
) -> Option<(Option<Suggestion>, Vec<String>)> {
|
|
let mut crate_module = if let ModuleOrUniformRoot::Module(module) = module {
|
|
module
|
|
} else {
|
|
return None;
|
|
};
|
|
|
|
while let Some(parent) = crate_module.parent {
|
|
crate_module = parent;
|
|
}
|
|
|
|
if ModuleOrUniformRoot::same_def(ModuleOrUniformRoot::Module(crate_module), module) {
|
|
// Don't make a suggestion if the import was already from the root of the
|
|
// crate.
|
|
return None;
|
|
}
|
|
|
|
let resolutions = crate_module.resolutions.borrow();
|
|
let resolution = resolutions.get(&(ident, MacroNS))?;
|
|
let binding = resolution.borrow().binding()?;
|
|
if let Res::Def(DefKind::Macro(MacroKind::Bang), _) = binding.res() {
|
|
let module_name = crate_module.kind.name().unwrap();
|
|
let import = match directive.subclass {
|
|
ImportDirectiveSubclass::SingleImport { source, target, .. } if source != target =>
|
|
format!("{} as {}", source, target),
|
|
_ => format!("{}", ident),
|
|
};
|
|
|
|
let mut corrections: Vec<(Span, String)> = Vec::new();
|
|
if !directive.is_nested() {
|
|
// Assume this is the easy case of `use issue_59764::foo::makro;` and just remove
|
|
// intermediate segments.
|
|
corrections.push((directive.span, format!("{}::{}", module_name, import)));
|
|
} else {
|
|
// Find the binding span (and any trailing commas and spaces).
|
|
// ie. `use a::b::{c, d, e};`
|
|
// ^^^
|
|
let (found_closing_brace, binding_span) = find_span_of_binding_until_next_binding(
|
|
self.resolver.session, directive.span, directive.use_span,
|
|
);
|
|
debug!("check_for_module_export_macro: found_closing_brace={:?} binding_span={:?}",
|
|
found_closing_brace, binding_span);
|
|
|
|
let mut removal_span = binding_span;
|
|
if found_closing_brace {
|
|
// If the binding span ended with a closing brace, as in the below example:
|
|
// ie. `use a::b::{c, d};`
|
|
// ^
|
|
// Then expand the span of characters to remove to include the previous
|
|
// binding's trailing comma.
|
|
// ie. `use a::b::{c, d};`
|
|
// ^^^
|
|
if let Some(previous_span) = extend_span_to_previous_binding(
|
|
self.resolver.session, binding_span,
|
|
) {
|
|
debug!("check_for_module_export_macro: previous_span={:?}", previous_span);
|
|
removal_span = removal_span.with_lo(previous_span.lo());
|
|
}
|
|
}
|
|
debug!("check_for_module_export_macro: removal_span={:?}", removal_span);
|
|
|
|
// Remove the `removal_span`.
|
|
corrections.push((removal_span, "".to_string()));
|
|
|
|
// Find the span after the crate name and if it has nested imports immediatately
|
|
// after the crate name already.
|
|
// ie. `use a::b::{c, d};`
|
|
// ^^^^^^^^^
|
|
// or `use a::{b, c, d}};`
|
|
// ^^^^^^^^^^^
|
|
let (has_nested, after_crate_name) = find_span_immediately_after_crate_name(
|
|
self.resolver.session, module_name, directive.use_span,
|
|
);
|
|
debug!("check_for_module_export_macro: has_nested={:?} after_crate_name={:?}",
|
|
has_nested, after_crate_name);
|
|
|
|
let source_map = self.resolver.session.source_map();
|
|
|
|
// Add the import to the start, with a `{` if required.
|
|
let start_point = source_map.start_point(after_crate_name);
|
|
if let Ok(start_snippet) = source_map.span_to_snippet(start_point) {
|
|
corrections.push((
|
|
start_point,
|
|
if has_nested {
|
|
// In this case, `start_snippet` must equal '{'.
|
|
format!("{}{}, ", start_snippet, import)
|
|
} else {
|
|
// In this case, add a `{`, then the moved import, then whatever
|
|
// was there before.
|
|
format!("{{{}, {}", import, start_snippet)
|
|
}
|
|
));
|
|
}
|
|
|
|
// Add a `};` to the end if nested, matching the `{` added at the start.
|
|
if !has_nested {
|
|
corrections.push((source_map.end_point(after_crate_name),
|
|
"};".to_string()));
|
|
}
|
|
}
|
|
|
|
let suggestion = Some((
|
|
corrections,
|
|
String::from("a macro with this name exists at the root of the crate"),
|
|
Applicability::MaybeIncorrect,
|
|
));
|
|
let note = vec![
|
|
"this could be because a macro annotated with `#[macro_export]` will be exported \
|
|
at the root of the crate instead of the module where it is defined".to_string(),
|
|
];
|
|
Some((suggestion, note))
|
|
} else {
|
|
None
|
|
}
|
|
}
|
|
}
|
|
|
|
/// Given a `binding_span` of a binding within a use statement:
|
|
///
|
|
/// ```
|
|
/// use foo::{a, b, c};
|
|
/// ^
|
|
/// ```
|
|
///
|
|
/// then return the span until the next binding or the end of the statement:
|
|
///
|
|
/// ```
|
|
/// use foo::{a, b, c};
|
|
/// ^^^
|
|
/// ```
|
|
pub(crate) fn find_span_of_binding_until_next_binding(
|
|
sess: &Session,
|
|
binding_span: Span,
|
|
use_span: Span,
|
|
) -> (bool, Span) {
|
|
let source_map = sess.source_map();
|
|
|
|
// Find the span of everything after the binding.
|
|
// ie. `a, e};` or `a};`
|
|
let binding_until_end = binding_span.with_hi(use_span.hi());
|
|
|
|
// Find everything after the binding but not including the binding.
|
|
// ie. `, e};` or `};`
|
|
let after_binding_until_end = binding_until_end.with_lo(binding_span.hi());
|
|
|
|
// Keep characters in the span until we encounter something that isn't a comma or
|
|
// whitespace.
|
|
// ie. `, ` or ``.
|
|
//
|
|
// Also note whether a closing brace character was encountered. If there
|
|
// was, then later go backwards to remove any trailing commas that are left.
|
|
let mut found_closing_brace = false;
|
|
let after_binding_until_next_binding = source_map.span_take_while(
|
|
after_binding_until_end,
|
|
|&ch| {
|
|
if ch == '}' { found_closing_brace = true; }
|
|
ch == ' ' || ch == ','
|
|
}
|
|
);
|
|
|
|
// Combine the two spans.
|
|
// ie. `a, ` or `a`.
|
|
//
|
|
// Removing these would leave `issue_52891::{d, e};` or `issue_52891::{d, e, };`
|
|
let span = binding_span.with_hi(after_binding_until_next_binding.hi());
|
|
|
|
(found_closing_brace, span)
|
|
}
|
|
|
|
/// Given a `binding_span`, return the span through to the comma or opening brace of the previous
|
|
/// binding.
|
|
///
|
|
/// ```
|
|
/// use foo::a::{a, b, c};
|
|
/// ^^--- binding span
|
|
/// |
|
|
/// returned span
|
|
///
|
|
/// use foo::{a, b, c};
|
|
/// --- binding span
|
|
/// ```
|
|
pub(crate) fn extend_span_to_previous_binding(
|
|
sess: &Session,
|
|
binding_span: Span,
|
|
) -> Option<Span> {
|
|
let source_map = sess.source_map();
|
|
|
|
// `prev_source` will contain all of the source that came before the span.
|
|
// Then split based on a command and take the first (ie. closest to our span)
|
|
// snippet. In the example, this is a space.
|
|
let prev_source = source_map.span_to_prev_source(binding_span).ok()?;
|
|
|
|
let prev_comma = prev_source.rsplit(',').collect::<Vec<_>>();
|
|
let prev_starting_brace = prev_source.rsplit('{').collect::<Vec<_>>();
|
|
if prev_comma.len() <= 1 || prev_starting_brace.len() <= 1 {
|
|
return None;
|
|
}
|
|
|
|
let prev_comma = prev_comma.first().unwrap();
|
|
let prev_starting_brace = prev_starting_brace.first().unwrap();
|
|
|
|
// If the amount of source code before the comma is greater than
|
|
// the amount of source code before the starting brace then we've only
|
|
// got one item in the nested item (eg. `issue_52891::{self}`).
|
|
if prev_comma.len() > prev_starting_brace.len() {
|
|
return None;
|
|
}
|
|
|
|
Some(binding_span.with_lo(BytePos(
|
|
// Take away the number of bytes for the characters we've found and an
|
|
// extra for the comma.
|
|
binding_span.lo().0 - (prev_comma.as_bytes().len() as u32) - 1
|
|
)))
|
|
}
|
|
|
|
/// Given a `use_span` of a binding within a use statement, returns the highlighted span and if
|
|
/// it is a nested use tree.
|
|
///
|
|
/// ```
|
|
/// use foo::a::{b, c};
|
|
/// ^^^^^^^^^^ // false
|
|
///
|
|
/// use foo::{a, b, c};
|
|
/// ^^^^^^^^^^ // true
|
|
///
|
|
/// use foo::{a, b::{c, d}};
|
|
/// ^^^^^^^^^^^^^^^ // true
|
|
/// ```
|
|
fn find_span_immediately_after_crate_name(
|
|
sess: &Session,
|
|
module_name: Symbol,
|
|
use_span: Span,
|
|
) -> (bool, Span) {
|
|
debug!("find_span_immediately_after_crate_name: module_name={:?} use_span={:?}",
|
|
module_name, use_span);
|
|
let source_map = sess.source_map();
|
|
|
|
// Using `use issue_59764::foo::{baz, makro};` as an example throughout..
|
|
let mut num_colons = 0;
|
|
// Find second colon.. `use issue_59764:`
|
|
let until_second_colon = source_map.span_take_while(use_span, |c| {
|
|
if *c == ':' { num_colons += 1; }
|
|
match c {
|
|
':' if num_colons == 2 => false,
|
|
_ => true,
|
|
}
|
|
});
|
|
// Find everything after the second colon.. `foo::{baz, makro};`
|
|
let from_second_colon = use_span.with_lo(until_second_colon.hi() + BytePos(1));
|
|
|
|
let mut found_a_non_whitespace_character = false;
|
|
// Find the first non-whitespace character in `from_second_colon`.. `f`
|
|
let after_second_colon = source_map.span_take_while(from_second_colon, |c| {
|
|
if found_a_non_whitespace_character { return false; }
|
|
if !c.is_whitespace() { found_a_non_whitespace_character = true; }
|
|
true
|
|
});
|
|
|
|
// Find the first `{` in from_second_colon.. `foo::{`
|
|
let next_left_bracket = source_map.span_through_char(from_second_colon, '{');
|
|
|
|
(next_left_bracket == after_second_colon, from_second_colon)
|
|
}
|