Adjusted diagnostic output so that if there is no use in a item sequence,
then we just suggest the first legal position where you could inject a use. To do this, I added `inject_use_span` field to `ModSpans`, and populate it in parser (it is the span of the first token found after inner attributes, if any). Then I rewrote the use-suggestion code to utilize it, and threw out some stuff that is now unnecessary with this in place. (I think the result is easier to understand.) Then I added a test of issue 87613.
This commit is contained in:
Felix S. Klock II
parent
b82795244e
commit
d37da1e332
@ -2322,16 +2322,17 @@ pub enum ModKind {
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Unloaded,
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}
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#[derive(Clone, Encodable, Decodable, Debug)]
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#[derive(Copy, Clone, Encodable, Decodable, Debug)]
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pub struct ModSpans {
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/// `inner_span` covers the body of the module; for a file module, its the whole file.
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/// For an inline module, its the span inside the `{ ... }`, not including the curly braces.
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pub inner_span: Span,
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pub inject_use_span: Span,
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}
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impl Default for ModSpans {
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fn default() -> ModSpans {
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ModSpans { inner_span: Default::default() }
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ModSpans { inner_span: Default::default(), inject_use_span: Default::default() }
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}
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}
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@ -1009,8 +1009,9 @@ pub fn noop_visit_item_kind<T: MutVisitor>(kind: &mut ItemKind, vis: &mut T) {
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ItemKind::Mod(unsafety, mod_kind) => {
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visit_unsafety(unsafety, vis);
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match mod_kind {
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ModKind::Loaded(items, _inline, ModSpans { inner_span }) => {
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ModKind::Loaded(items, _inline, ModSpans { inner_span, inject_use_span }) => {
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vis.visit_span(inner_span);
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vis.visit_span(inject_use_span);
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items.flat_map_in_place(|item| vis.flat_map_item(item));
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}
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ModKind::Unloaded => {}
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@ -1112,8 +1113,9 @@ pub fn noop_visit_crate<T: MutVisitor>(krate: &mut Crate, vis: &mut T) {
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vis.visit_id(id);
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visit_attrs(attrs, vis);
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items.flat_map_in_place(|item| vis.flat_map_item(item));
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let ModSpans { inner_span } = spans;
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let ModSpans { inner_span, inject_use_span } = spans;
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vis.visit_span(inner_span);
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vis.visit_span(inject_use_span);
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}
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// Mutates one item into possibly many items.
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@ -263,7 +263,7 @@ fn lower_item_kind(
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})
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}
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ItemKind::Mod(_, ref mod_kind) => match mod_kind {
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ModKind::Loaded(items, _, ModSpans { inner_span }) => {
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ModKind::Loaded(items, _, ModSpans { inner_span, inject_use_span: _ }) => {
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hir::ItemKind::Mod(self.lower_mod(items, *inner_span))
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}
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ModKind::Unloaded => panic!("`mod` items should have been loaded by now"),
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@ -129,9 +129,8 @@ fn visit_crate(&mut self, c: &mut ast::Crate) {
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// We don't want to recurse into anything other than mods, since
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// mods or tests inside of functions will break things
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if let ast::ItemKind::Mod(_, ModKind::Loaded(.., ast::ModSpans { inner_span: span })) =
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item.kind
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{
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if let ast::ItemKind::Mod(_, ModKind::Loaded(.., ref spans)) = item.kind {
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let ast::ModSpans { inner_span: span, inject_use_span: _ } = *spans;
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let prev_tests = mem::take(&mut self.tests);
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noop_visit_item_kind(&mut item.kind, self);
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self.add_test_cases(item.id, span, prev_tests);
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@ -55,6 +55,7 @@ pub fn parse_mod(
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let lo = self.token.span;
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let attrs = self.parse_inner_attributes()?;
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let post_attr_lo = self.token.span;
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let mut items = vec![];
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while let Some(item) = self.parse_item(ForceCollect::No)? {
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items.push(item);
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@ -71,7 +72,9 @@ pub fn parse_mod(
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}
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}
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Ok((attrs, items, ModSpans { inner_span: lo.to(self.prev_token.span) }))
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let inject_use_span = post_attr_lo.data().with_hi(post_attr_lo.lo());
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let mod_spans = ModSpans { inner_span: lo.to(self.prev_token.span), inject_use_span };
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Ok((attrs, items, mod_spans))
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}
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}
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@ -71,7 +71,6 @@
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use smallvec::{smallvec, SmallVec};
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use std::cell::{Cell, RefCell};
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use std::collections::BTreeSet;
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use std::ops::ControlFlow;
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use std::{cmp, fmt, iter, mem, ptr};
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use tracing::debug;
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@ -315,74 +314,70 @@ fn from(seg: &'a ast::PathSegment) -> Segment {
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}
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}
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#[derive(Debug)]
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struct UsePlacementFinder {
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target_module: NodeId,
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span: Option<Span>,
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found_use: bool,
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first_legal_span: Option<Span>,
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first_use_span: Option<Span>,
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}
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impl UsePlacementFinder {
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fn check(krate: &Crate, target_module: NodeId) -> (Option<Span>, bool) {
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let mut finder = UsePlacementFinder { target_module, span: None, found_use: false };
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if let ControlFlow::Continue(..) = finder.check_mod(&krate.items, CRATE_NODE_ID) {
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visit::walk_crate(&mut finder, krate);
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let mut finder =
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UsePlacementFinder { target_module, first_legal_span: None, first_use_span: None };
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finder.visit_crate(krate);
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if let Some(use_span) = finder.first_use_span {
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(Some(use_span), true)
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} else {
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(finder.first_legal_span, false)
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}
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(finder.span, finder.found_use)
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}
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fn check_mod(&mut self, items: &[P<ast::Item>], node_id: NodeId) -> ControlFlow<()> {
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if self.span.is_some() {
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return ControlFlow::Break(());
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}
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if node_id != self.target_module {
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return ControlFlow::Continue(());
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}
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// find a use statement
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for item in items {
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match item.kind {
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ItemKind::Use(..) => {
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// don't suggest placing a use before the prelude
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// import or other generated ones
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if !item.span.from_expansion() {
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self.span = Some(item.span.shrink_to_lo());
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self.found_use = true;
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return ControlFlow::Break(());
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}
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}
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// don't place use before extern crate
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ItemKind::ExternCrate(_) => {}
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// but place them before the first other item
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_ => {
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if self.span.map_or(true, |span| item.span < span)
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&& !item.span.from_expansion()
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{
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self.span = Some(item.span.shrink_to_lo());
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// don't insert between attributes and an item
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// find the first attribute on the item
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// FIXME: This is broken for active attributes.
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for attr in &item.attrs {
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if !attr.span.is_dummy()
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&& self.span.map_or(true, |span| attr.span < span)
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{
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self.span = Some(attr.span.shrink_to_lo());
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}
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}
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}
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}
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}
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}
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ControlFlow::Continue(())
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}
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}
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impl<'tcx> Visitor<'tcx> for UsePlacementFinder {
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fn visit_item(&mut self, item: &'tcx ast::Item) {
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if let ItemKind::Mod(_, ModKind::Loaded(items, ..)) = &item.kind {
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if let ControlFlow::Break(..) = self.check_mod(items, item.id) {
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return;
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fn is_span_suitable_for_use_injection(s: Span) -> bool {
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// don't suggest placing a use before the prelude
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// import or other generated ones
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!s.from_expansion()
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}
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fn search_for_any_use_in_items(items: &[P<ast::Item>]) -> Option<Span> {
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for item in items {
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if let ItemKind::Use(..) = item.kind {
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if is_span_suitable_for_use_injection(item.span) {
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return Some(item.span.shrink_to_lo());
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}
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}
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visit::walk_item(self, item);
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}
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return None;
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}
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impl<'tcx> Visitor<'tcx> for UsePlacementFinder {
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fn visit_crate(&mut self, c: &Crate) {
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if self.target_module == CRATE_NODE_ID {
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let inject = c.spans.inject_use_span;
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if is_span_suitable_for_use_injection(inject) {
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self.first_legal_span = Some(inject);
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}
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self.first_use_span = search_for_any_use_in_items(&c.items);
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return;
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} else {
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visit::walk_crate(self, c);
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}
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}
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fn visit_item(&mut self, item: &'tcx ast::Item) {
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if self.target_module == item.id {
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if let ItemKind::Mod(_, ModKind::Loaded(items, _inline, mod_spans)) = &item.kind {
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let inject = mod_spans.inject_use_span;
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if is_span_suitable_for_use_injection(inject) {
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self.first_legal_span = Some(inject);
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}
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self.first_use_span = search_for_any_use_in_items(items);
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return;
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}
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} else {
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visit::walk_item(self, item);
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}
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}
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}
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@ -1 +1 @@
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{"attrs":[{"kind":{"variant":"Normal","fields":[{"path":{"span":{"lo":0,"hi":0},"segments":[{"ident":{"name":"crate_type","span":{"lo":0,"hi":0}},"id":0,"args":null}],"tokens":null},"args":{"variant":"Eq","fields":[{"lo":0,"hi":0},{"kind":{"variant":"Interpolated","fields":[{"variant":"NtExpr","fields":[{"id":0,"kind":{"variant":"Lit","fields":[{"token":{"kind":"Str","symbol":"lib","suffix":null},"kind":{"variant":"Str","fields":["lib","Cooked"]},"span":{"lo":0,"hi":0}}]},"span":{"lo":0,"hi":0},"attrs":{"0":null},"tokens":{"0":[[{"variant":"Token","fields":[{"kind":{"variant":"Literal","fields":[{"kind":"Str","symbol":"lib","suffix":null}]},"span":{"lo":0,"hi":0}}]},"Alone"]]}}]}]},"span":{"lo":0,"hi":0}}]},"tokens":null},{"0":[[{"variant":"Token","fields":[{"kind":"Pound","span":{"lo":0,"hi":0}}]},"Joint"],[{"variant":"Token","fields":[{"kind":"Not","span":{"lo":0,"hi":0}}]},"Alone"],[{"variant":"Delimited","fields":[{"open":{"lo":0,"hi":0},"close":{"lo":0,"hi":0}},"Bracket",{"0":[[{"variant":"Token","fields":[{"kind":{"variant":"Ident","fields":["crate_type",false]},"span":{"lo":0,"hi":0}}]},"Alone"],[{"variant":"Token","fields":[{"kind":"Eq","span":{"lo":0,"hi":0}}]},"Alone"],[{"variant":"Token","fields":[{"kind":{"variant":"Literal","fields":[{"kind":"Str","symbol":"lib","suffix":null}]},"span":{"lo":0,"hi":0}}]},"Alone"]]}]},"Alone"]]}]},"id":null,"style":"Inner","span":{"lo":0,"hi":0}}],"items":[{"attrs":[],"id":0,"span":{"lo":0,"hi":0},"vis":{"kind":"Inherited","span":{"lo":0,"hi":0},"tokens":null},"ident":{"name":"core","span":{"lo":0,"hi":0}},"kind":{"variant":"ExternCrate","fields":[null]},"tokens":null}],"spans":{"inner_span":{"lo":0,"hi":0}},"id":0,"is_placeholder":false}
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{"attrs":[{"kind":{"variant":"Normal","fields":[{"path":{"span":{"lo":0,"hi":0},"segments":[{"ident":{"name":"crate_type","span":{"lo":0,"hi":0}},"id":0,"args":null}],"tokens":null},"args":{"variant":"Eq","fields":[{"lo":0,"hi":0},{"kind":{"variant":"Interpolated","fields":[{"variant":"NtExpr","fields":[{"id":0,"kind":{"variant":"Lit","fields":[{"token":{"kind":"Str","symbol":"lib","suffix":null},"kind":{"variant":"Str","fields":["lib","Cooked"]},"span":{"lo":0,"hi":0}}]},"span":{"lo":0,"hi":0},"attrs":{"0":null},"tokens":{"0":[[{"variant":"Token","fields":[{"kind":{"variant":"Literal","fields":[{"kind":"Str","symbol":"lib","suffix":null}]},"span":{"lo":0,"hi":0}}]},"Alone"]]}}]}]},"span":{"lo":0,"hi":0}}]},"tokens":null},{"0":[[{"variant":"Token","fields":[{"kind":"Pound","span":{"lo":0,"hi":0}}]},"Joint"],[{"variant":"Token","fields":[{"kind":"Not","span":{"lo":0,"hi":0}}]},"Alone"],[{"variant":"Delimited","fields":[{"open":{"lo":0,"hi":0},"close":{"lo":0,"hi":0}},"Bracket",{"0":[[{"variant":"Token","fields":[{"kind":{"variant":"Ident","fields":["crate_type",false]},"span":{"lo":0,"hi":0}}]},"Alone"],[{"variant":"Token","fields":[{"kind":"Eq","span":{"lo":0,"hi":0}}]},"Alone"],[{"variant":"Token","fields":[{"kind":{"variant":"Literal","fields":[{"kind":"Str","symbol":"lib","suffix":null}]},"span":{"lo":0,"hi":0}}]},"Alone"]]}]},"Alone"]]}]},"id":null,"style":"Inner","span":{"lo":0,"hi":0}}],"items":[{"attrs":[],"id":0,"span":{"lo":0,"hi":0},"vis":{"kind":"Inherited","span":{"lo":0,"hi":0},"tokens":null},"ident":{"name":"core","span":{"lo":0,"hi":0}},"kind":{"variant":"ExternCrate","fields":[null]},"tokens":null}],"spans":{"inner_span":{"lo":0,"hi":0},"inject_use_span":{"lo":0,"hi":0}},"id":0,"is_placeholder":false}
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@ -1 +1 @@
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{"attrs":[{"kind":{"variant":"Normal","fields":[{"path":{"span":{"lo":0,"hi":0},"segments":[{"ident":{"name":"crate_type","span":{"lo":0,"hi":0}},"id":0,"args":null}],"tokens":null},"args":{"variant":"Eq","fields":[{"lo":0,"hi":0},{"kind":{"variant":"Interpolated","fields":[{"variant":"NtExpr","fields":[{"id":0,"kind":{"variant":"Lit","fields":[{"token":{"kind":"Str","symbol":"lib","suffix":null},"kind":{"variant":"Str","fields":["lib","Cooked"]},"span":{"lo":0,"hi":0}}]},"span":{"lo":0,"hi":0},"attrs":{"0":null},"tokens":{"0":[[{"variant":"Token","fields":[{"kind":{"variant":"Literal","fields":[{"kind":"Str","symbol":"lib","suffix":null}]},"span":{"lo":0,"hi":0}}]},"Alone"]]}}]}]},"span":{"lo":0,"hi":0}}]},"tokens":null},{"0":[[{"variant":"Token","fields":[{"kind":"Pound","span":{"lo":0,"hi":0}}]},"Joint"],[{"variant":"Token","fields":[{"kind":"Not","span":{"lo":0,"hi":0}}]},"Alone"],[{"variant":"Delimited","fields":[{"open":{"lo":0,"hi":0},"close":{"lo":0,"hi":0}},"Bracket",{"0":[[{"variant":"Token","fields":[{"kind":{"variant":"Ident","fields":["crate_type",false]},"span":{"lo":0,"hi":0}}]},"Alone"],[{"variant":"Token","fields":[{"kind":"Eq","span":{"lo":0,"hi":0}}]},"Alone"],[{"variant":"Token","fields":[{"kind":{"variant":"Literal","fields":[{"kind":"Str","symbol":"lib","suffix":null}]},"span":{"lo":0,"hi":0}}]},"Alone"]]}]},"Alone"]]}]},"id":null,"style":"Inner","span":{"lo":0,"hi":0}}],"items":[{"attrs":[{"kind":{"variant":"Normal","fields":[{"path":{"span":{"lo":0,"hi":0},"segments":[{"ident":{"name":"prelude_import","span":{"lo":0,"hi":0}},"id":0,"args":null}],"tokens":null},"args":"Empty","tokens":null},null]},"id":null,"style":"Outer","span":{"lo":0,"hi":0}}],"id":0,"span":{"lo":0,"hi":0},"vis":{"kind":"Inherited","span":{"lo":0,"hi":0},"tokens":null},"ident":{"name":"","span":{"lo":0,"hi":0}},"kind":{"variant":"Use","fields":[{"prefix":{"span":{"lo":0,"hi":0},"segments":[{"ident":{"name":"{{root}}","span":{"lo":0,"hi":0}},"id":0,"args":null},{"ident":{"name":"std","span":{"lo":0,"hi":0}},"id":0,"args":null},{"ident":{"name":"prelude","span":{"lo":0,"hi":0}},"id":0,"args":null},{"ident":{"name":"rust_2015","span":{"lo":0,"hi":0}},"id":0,"args":null}],"tokens":null},"kind":"Glob","span":{"lo":0,"hi":0}}]},"tokens":null},{"attrs":[{"kind":{"variant":"Normal","fields":[{"path":{"span":{"lo":0,"hi":0},"segments":[{"ident":{"name":"macro_use","span":{"lo":0,"hi":0}},"id":0,"args":null}],"tokens":null},"args":"Empty","tokens":null},null]},"id":null,"style":"Outer","span":{"lo":0,"hi":0}}],"id":0,"span":{"lo":0,"hi":0},"vis":{"kind":"Inherited","span":{"lo":0,"hi":0},"tokens":null},"ident":{"name":"std","span":{"lo":0,"hi":0}},"kind":{"variant":"ExternCrate","fields":[null]},"tokens":null},{"attrs":[],"id":0,"span":{"lo":0,"hi":0},"vis":{"kind":"Inherited","span":{"lo":0,"hi":0},"tokens":null},"ident":{"name":"core","span":{"lo":0,"hi":0}},"kind":{"variant":"ExternCrate","fields":[null]},"tokens":null}],"spans":{"inner_span":{"lo":0,"hi":0}},"id":0,"is_placeholder":false}
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{"attrs":[{"kind":{"variant":"Normal","fields":[{"path":{"span":{"lo":0,"hi":0},"segments":[{"ident":{"name":"crate_type","span":{"lo":0,"hi":0}},"id":0,"args":null}],"tokens":null},"args":{"variant":"Eq","fields":[{"lo":0,"hi":0},{"kind":{"variant":"Interpolated","fields":[{"variant":"NtExpr","fields":[{"id":0,"kind":{"variant":"Lit","fields":[{"token":{"kind":"Str","symbol":"lib","suffix":null},"kind":{"variant":"Str","fields":["lib","Cooked"]},"span":{"lo":0,"hi":0}}]},"span":{"lo":0,"hi":0},"attrs":{"0":null},"tokens":{"0":[[{"variant":"Token","fields":[{"kind":{"variant":"Literal","fields":[{"kind":"Str","symbol":"lib","suffix":null}]},"span":{"lo":0,"hi":0}}]},"Alone"]]}}]}]},"span":{"lo":0,"hi":0}}]},"tokens":null},{"0":[[{"variant":"Token","fields":[{"kind":"Pound","span":{"lo":0,"hi":0}}]},"Joint"],[{"variant":"Token","fields":[{"kind":"Not","span":{"lo":0,"hi":0}}]},"Alone"],[{"variant":"Delimited","fields":[{"open":{"lo":0,"hi":0},"close":{"lo":0,"hi":0}},"Bracket",{"0":[[{"variant":"Token","fields":[{"kind":{"variant":"Ident","fields":["crate_type",false]},"span":{"lo":0,"hi":0}}]},"Alone"],[{"variant":"Token","fields":[{"kind":"Eq","span":{"lo":0,"hi":0}}]},"Alone"],[{"variant":"Token","fields":[{"kind":{"variant":"Literal","fields":[{"kind":"Str","symbol":"lib","suffix":null}]},"span":{"lo":0,"hi":0}}]},"Alone"]]}]},"Alone"]]}]},"id":null,"style":"Inner","span":{"lo":0,"hi":0}}],"items":[{"attrs":[{"kind":{"variant":"Normal","fields":[{"path":{"span":{"lo":0,"hi":0},"segments":[{"ident":{"name":"prelude_import","span":{"lo":0,"hi":0}},"id":0,"args":null}],"tokens":null},"args":"Empty","tokens":null},null]},"id":null,"style":"Outer","span":{"lo":0,"hi":0}}],"id":0,"span":{"lo":0,"hi":0},"vis":{"kind":"Inherited","span":{"lo":0,"hi":0},"tokens":null},"ident":{"name":"","span":{"lo":0,"hi":0}},"kind":{"variant":"Use","fields":[{"prefix":{"span":{"lo":0,"hi":0},"segments":[{"ident":{"name":"{{root}}","span":{"lo":0,"hi":0}},"id":0,"args":null},{"ident":{"name":"std","span":{"lo":0,"hi":0}},"id":0,"args":null},{"ident":{"name":"prelude","span":{"lo":0,"hi":0}},"id":0,"args":null},{"ident":{"name":"rust_2015","span":{"lo":0,"hi":0}},"id":0,"args":null}],"tokens":null},"kind":"Glob","span":{"lo":0,"hi":0}}]},"tokens":null},{"attrs":[{"kind":{"variant":"Normal","fields":[{"path":{"span":{"lo":0,"hi":0},"segments":[{"ident":{"name":"macro_use","span":{"lo":0,"hi":0}},"id":0,"args":null}],"tokens":null},"args":"Empty","tokens":null},null]},"id":null,"style":"Outer","span":{"lo":0,"hi":0}}],"id":0,"span":{"lo":0,"hi":0},"vis":{"kind":"Inherited","span":{"lo":0,"hi":0},"tokens":null},"ident":{"name":"std","span":{"lo":0,"hi":0}},"kind":{"variant":"ExternCrate","fields":[null]},"tokens":null},{"attrs":[],"id":0,"span":{"lo":0,"hi":0},"vis":{"kind":"Inherited","span":{"lo":0,"hi":0},"tokens":null},"ident":{"name":"core","span":{"lo":0,"hi":0}},"kind":{"variant":"ExternCrate","fields":[null]},"tokens":null}],"spans":{"inner_span":{"lo":0,"hi":0},"inject_use_span":{"lo":0,"hi":0}},"id":0,"is_placeholder":false}
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63
src/test/ui/proc-macro/amputate-span.rs
Normal file
63
src/test/ui/proc-macro/amputate-span.rs
Normal file
@ -0,0 +1,63 @@
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// aux-build:amputate-span.rs
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// edition:2018
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// compile-flags: --extern amputate_span
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// This test has been crafted to ensure the following things:
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//
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// 1. There's a resolution error that prompts the compiler to suggest
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// adding a `use` item.
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//
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// 2. There are no `use` or `extern crate` items in the source
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// code. In fact, there is only one item, the `fn main`
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// declaration.
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//
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// 3. The single `fn main` declaration has an attribute attached to it
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// that just deletes the first token from the given item.
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//
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// You need all of these conditions to hold in order to replicate the
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||||
// scenario that yielded issue 87613, where the compiler's suggestion
|
||||
// looks like:
|
||||
//
|
||||
// ```
|
||||
// help: consider importing this struct
|
||||
// |
|
||||
// 47 | hey */ async use std::process::Command;
|
||||
// | ++++++++++++++++++++++++++
|
||||
// ```
|
||||
//
|
||||
// The first condition is necessary to force the compiler issue a
|
||||
// suggestion. The second condition is necessary to force the
|
||||
// suggestion to be issued at a span associated with the sole
|
||||
// `fn`-item of this crate. The third condition is necessary in order
|
||||
// to yield the weird state where the associated span of the `fn`-item
|
||||
// does not actually cover all of the original source code of the
|
||||
// `fn`-item (which is why we are calling it an "amputated" span
|
||||
// here).
|
||||
//
|
||||
// Note that satisfying conditions 2 and 3 requires the use of the
|
||||
// `--extern` compile flag.
|
||||
//
|
||||
// You might ask yourself: What code would do such a thing? The
|
||||
// answer is: the #[tokio::main] attribute does *exactly* this (as
|
||||
// well as injecting some other code into the `fn main` that it
|
||||
// constructs).
|
||||
|
||||
#[amputate_span::drop_first_token]
|
||||
/* what the
|
||||
hey */ async fn main() {
|
||||
Command::new("git"); //~ ERROR [E0433]
|
||||
}
|
||||
|
||||
// (The /* ... */ comment in the above is not part of the original
|
||||
// bug. It is just meant to illustrate one particular facet of the
|
||||
// original non-ideal behavior, where we were transcribing the
|
||||
// trailing comment as part of the emitted suggestion, for better or
|
||||
// for worse.)
|
||||
|
||||
mod inner {
|
||||
#[amputate_span::drop_first_token]
|
||||
/* another interesting
|
||||
case */ async fn foo() {
|
||||
Command::new("git"); //~ ERROR [E0433]
|
||||
}
|
||||
}
|
||||
25
src/test/ui/proc-macro/amputate-span.stderr
Normal file
25
src/test/ui/proc-macro/amputate-span.stderr
Normal file
@ -0,0 +1,25 @@
|
||||
error[E0433]: failed to resolve: use of undeclared type `Command`
|
||||
--> $DIR/amputate-span.rs:48:5
|
||||
|
|
||||
LL | Command::new("git");
|
||||
| ^^^^^^^ not found in this scope
|
||||
|
|
||||
help: consider importing this struct
|
||||
|
|
||||
LL | use std::process::Command;
|
||||
|
|
||||
|
||||
error[E0433]: failed to resolve: use of undeclared type `Command`
|
||||
--> $DIR/amputate-span.rs:61:9
|
||||
|
|
||||
LL | Command::new("git");
|
||||
| ^^^^^^^ not found in this scope
|
||||
|
|
||||
help: consider importing this struct
|
||||
|
|
||||
LL | use std::process::Command;
|
||||
|
|
||||
|
||||
error: aborting due to 2 previous errors
|
||||
|
||||
For more information about this error, try `rustc --explain E0433`.
|
||||
14
src/test/ui/proc-macro/auxiliary/amputate-span.rs
Normal file
14
src/test/ui/proc-macro/auxiliary/amputate-span.rs
Normal file
@ -0,0 +1,14 @@
|
||||
// force-host
|
||||
// no-prefer-dynamic
|
||||
|
||||
#![crate_type = "proc-macro"]
|
||||
|
||||
extern crate proc_macro;
|
||||
|
||||
use proc_macro::TokenStream;
|
||||
|
||||
#[proc_macro_attribute]
|
||||
pub fn drop_first_token(attr: TokenStream, input: TokenStream) -> TokenStream {
|
||||
assert!(attr.is_empty());
|
||||
input.into_iter().skip(1).collect()
|
||||
}
|
||||
@ -113,7 +113,7 @@ pub(crate) fn parse_file_as_module(
|
||||
let result = catch_unwind(AssertUnwindSafe(|| {
|
||||
let mut parser = new_parser_from_file(sess.inner(), path, Some(span));
|
||||
match parser.parse_mod(&TokenKind::Eof) {
|
||||
Ok((a, i, ast::ModSpans { inner_span })) => Some((a, i, inner_span)),
|
||||
Ok((a, i, ast::ModSpans { inner_span, inject_use_span: _ })) => Some((a, i, inner_span)),
|
||||
Err(mut e) => {
|
||||
e.emit();
|
||||
if sess.can_reset_errors() {
|
||||
|
||||
@ -916,7 +916,7 @@ fn format_mod(
|
||||
self.push_str(&ident_str);
|
||||
|
||||
if let ast::ModKind::Loaded(ref items, ast::Inline::Yes, ref spans) = mod_kind {
|
||||
let ast::ModSpans { inner_span } = *spans;
|
||||
let ast::ModSpans{ inner_span, inject_use_span: _ } = *spans;
|
||||
match self.config.brace_style() {
|
||||
BraceStyle::AlwaysNextLine => {
|
||||
let indent_str = self.block_indent.to_string_with_newline(self.config);
|
||||
|
||||
Loading…
Reference in New Issue
Block a user