Rollup merge of #50854 - zackmdavis:and_the_case_of_the_unused_field_pattern_3_straight_to_video, r=estebank
in which the unused shorthand field pattern debacle/saga continues
In e4b1a79 (#47922), we corrected erroneous suggestions for unused
shorthand field pattern bindings, suggesting `field: _` where the
previous suggestion of `_field` wouldn't even have compiled
(#47390). Soon, it was revealed that this was insufficient (#50303), and
the fix was extended to references, slices, &c. (#50327) But even this
proved inadequate, as the erroneous suggestions were still being issued
for patterns in local (`let`) bindings (#50804). Here, we yank the
shorthand-detection and variable/node registration code into a new
common function that can be called while visiting both match arms and
`let` bindings.
Resolves #50804.
r? @estebank
This commit is contained in:
kennytm
commit
907288c73f
3 changed files with 80 additions and 71 deletions
|
|
@ -117,6 +117,7 @@ use std::io::prelude::*;
|
|||
use std::io;
|
||||
use std::rc::Rc;
|
||||
use syntax::ast::{self, NodeId};
|
||||
use syntax::ptr::P;
|
||||
use syntax::symbol::keywords;
|
||||
use syntax_pos::Span;
|
||||
|
||||
|
|
@ -398,72 +399,65 @@ fn visit_fn<'a, 'tcx: 'a>(ir: &mut IrMaps<'a, 'tcx>,
|
|||
lsets.warn_about_unused_args(body, entry_ln);
|
||||
}
|
||||
|
||||
fn visit_local<'a, 'tcx>(ir: &mut IrMaps<'a, 'tcx>, local: &'tcx hir::Local) {
|
||||
local.pat.each_binding(|_, p_id, sp, path1| {
|
||||
debug!("adding local variable {}", p_id);
|
||||
fn add_from_pat<'a, 'tcx>(ir: &mut IrMaps<'a, 'tcx>, pat: &P<hir::Pat>) {
|
||||
// For struct patterns, take note of which fields used shorthand
|
||||
// (`x` rather than `x: x`).
|
||||
//
|
||||
// FIXME: according to the rust-lang-nursery/rustc-guide book, `NodeId`s are to be
|
||||
// phased out in favor of `HirId`s; however, we need to match the signature of
|
||||
// `each_binding`, which uses `NodeIds`.
|
||||
let mut shorthand_field_ids = NodeSet();
|
||||
let mut pats = VecDeque::new();
|
||||
pats.push_back(pat);
|
||||
while let Some(pat) = pats.pop_front() {
|
||||
use hir::PatKind::*;
|
||||
match pat.node {
|
||||
Binding(_, _, _, ref inner_pat) => {
|
||||
pats.extend(inner_pat.iter());
|
||||
}
|
||||
Struct(_, ref fields, _) => {
|
||||
for field in fields {
|
||||
if field.node.is_shorthand {
|
||||
shorthand_field_ids.insert(field.node.pat.id);
|
||||
}
|
||||
}
|
||||
}
|
||||
Ref(ref inner_pat, _) |
|
||||
Box(ref inner_pat) => {
|
||||
pats.push_back(inner_pat);
|
||||
}
|
||||
TupleStruct(_, ref inner_pats, _) |
|
||||
Tuple(ref inner_pats, _) => {
|
||||
pats.extend(inner_pats.iter());
|
||||
}
|
||||
Slice(ref pre_pats, ref inner_pat, ref post_pats) => {
|
||||
pats.extend(pre_pats.iter());
|
||||
pats.extend(inner_pat.iter());
|
||||
pats.extend(post_pats.iter());
|
||||
}
|
||||
_ => {}
|
||||
}
|
||||
}
|
||||
|
||||
pat.each_binding(|_bm, p_id, _sp, path1| {
|
||||
let name = path1.node;
|
||||
ir.add_live_node_for_node(p_id, VarDefNode(sp));
|
||||
ir.add_live_node_for_node(p_id, VarDefNode(path1.span));
|
||||
ir.add_variable(Local(LocalInfo {
|
||||
id: p_id,
|
||||
name,
|
||||
is_shorthand: false,
|
||||
is_shorthand: shorthand_field_ids.contains(&p_id)
|
||||
}));
|
||||
});
|
||||
}
|
||||
|
||||
fn visit_local<'a, 'tcx>(ir: &mut IrMaps<'a, 'tcx>, local: &'tcx hir::Local) {
|
||||
add_from_pat(ir, &local.pat);
|
||||
intravisit::walk_local(ir, local);
|
||||
}
|
||||
|
||||
fn visit_arm<'a, 'tcx>(ir: &mut IrMaps<'a, 'tcx>, arm: &'tcx hir::Arm) {
|
||||
for mut pat in &arm.pats {
|
||||
// For struct patterns, take note of which fields used shorthand
|
||||
// (`x` rather than `x: x`).
|
||||
//
|
||||
// FIXME: according to the rust-lang-nursery/rustc-guide book, `NodeId`s are to be
|
||||
// phased out in favor of `HirId`s; however, we need to match the signature of
|
||||
// `each_binding`, which uses `NodeIds`.
|
||||
let mut shorthand_field_ids = NodeSet();
|
||||
let mut pats = VecDeque::new();
|
||||
pats.push_back(pat);
|
||||
while let Some(pat) = pats.pop_front() {
|
||||
use hir::PatKind::*;
|
||||
match pat.node {
|
||||
Binding(_, _, _, ref inner_pat) => {
|
||||
pats.extend(inner_pat.iter());
|
||||
}
|
||||
Struct(_, ref fields, _) => {
|
||||
for field in fields {
|
||||
if field.node.is_shorthand {
|
||||
shorthand_field_ids.insert(field.node.pat.id);
|
||||
}
|
||||
}
|
||||
}
|
||||
Ref(ref inner_pat, _) |
|
||||
Box(ref inner_pat) => {
|
||||
pats.push_back(inner_pat);
|
||||
}
|
||||
TupleStruct(_, ref inner_pats, _) |
|
||||
Tuple(ref inner_pats, _) => {
|
||||
pats.extend(inner_pats.iter());
|
||||
}
|
||||
Slice(ref pre_pats, ref inner_pat, ref post_pats) => {
|
||||
pats.extend(pre_pats.iter());
|
||||
pats.extend(inner_pat.iter());
|
||||
pats.extend(post_pats.iter());
|
||||
}
|
||||
_ => {}
|
||||
}
|
||||
}
|
||||
|
||||
pat.each_binding(|bm, p_id, _sp, path1| {
|
||||
debug!("adding local variable {} from match with bm {:?}",
|
||||
p_id, bm);
|
||||
let name = path1.node;
|
||||
ir.add_live_node_for_node(p_id, VarDefNode(path1.span));
|
||||
ir.add_variable(Local(LocalInfo {
|
||||
id: p_id,
|
||||
name: name,
|
||||
is_shorthand: shorthand_field_ids.contains(&p_id)
|
||||
}));
|
||||
})
|
||||
for pat in &arm.pats {
|
||||
add_from_pat(ir, pat);
|
||||
}
|
||||
intravisit::walk_arm(ir, arm);
|
||||
}
|
||||
|
|
|
|||
|
|
@ -20,6 +20,11 @@ struct SoulHistory {
|
|||
endless_and_singing: bool
|
||||
}
|
||||
|
||||
struct LovelyAmbition {
|
||||
lips: usize,
|
||||
fire: usize
|
||||
}
|
||||
|
||||
#[derive(Clone, Copy)]
|
||||
enum Large {
|
||||
Suit { case: () }
|
||||
|
|
@ -45,6 +50,10 @@ fn main() {
|
|||
hours_are_suns = false;
|
||||
}
|
||||
|
||||
let the_spirit = LovelyAmbition { lips: 1, fire: 2 };
|
||||
let LovelyAmbition { lips, fire } = the_spirit;
|
||||
println!("{}", lips);
|
||||
|
||||
let bag = Large::Suit {
|
||||
case: ()
|
||||
};
|
||||
|
|
|
|||
|
|
@ -1,5 +1,5 @@
|
|||
warning: unused variable: `i_think_continually`
|
||||
--> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:31:9
|
||||
--> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:36:9
|
||||
|
|
||||
LL | let i_think_continually = 2;
|
||||
| ^^^^^^^^^^^^^^^^^^^ help: consider using `_i_think_continually` instead
|
||||
|
|
@ -12,31 +12,31 @@ LL | #![warn(unused)] // UI tests pass `-A unused` (#43896)
|
|||
= note: #[warn(unused_variables)] implied by #[warn(unused)]
|
||||
|
||||
warning: unused variable: `mut_unused_var`
|
||||
--> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:38:13
|
||||
--> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:43:13
|
||||
|
|
||||
LL | let mut mut_unused_var = 1;
|
||||
| ^^^^^^^^^^^^^^ help: consider using `_mut_unused_var` instead
|
||||
|
||||
warning: unused variable: `var`
|
||||
--> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:40:14
|
||||
--> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:45:14
|
||||
|
|
||||
LL | let (mut var, unused_var) = (1, 2);
|
||||
| ^^^ help: consider using `_var` instead
|
||||
|
||||
warning: unused variable: `unused_var`
|
||||
--> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:40:19
|
||||
--> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:45:19
|
||||
|
|
||||
LL | let (mut var, unused_var) = (1, 2);
|
||||
| ^^^^^^^^^^ help: consider using `_unused_var` instead
|
||||
|
||||
warning: unused variable: `corridors_of_light`
|
||||
--> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:42:26
|
||||
--> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:47:26
|
||||
|
|
||||
LL | if let SoulHistory { corridors_of_light,
|
||||
| ^^^^^^^^^^^^^^^^^^ help: try ignoring the field: `corridors_of_light: _`
|
||||
|
||||
warning: variable `hours_are_suns` is assigned to, but never used
|
||||
--> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:43:30
|
||||
--> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:48:30
|
||||
|
|
||||
LL | mut hours_are_suns,
|
||||
| ^^^^^^^^^^^^^^
|
||||
|
|
@ -44,7 +44,7 @@ LL | mut hours_are_suns,
|
|||
= note: consider using `_hours_are_suns` instead
|
||||
|
||||
warning: value assigned to `hours_are_suns` is never read
|
||||
--> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:45:9
|
||||
--> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:50:9
|
||||
|
|
||||
LL | hours_are_suns = false;
|
||||
| ^^^^^^^^^^^^^^
|
||||
|
|
@ -56,44 +56,50 @@ LL | #![warn(unused)] // UI tests pass `-A unused` (#43896)
|
|||
| ^^^^^^
|
||||
= note: #[warn(unused_assignments)] implied by #[warn(unused)]
|
||||
|
||||
warning: unused variable: `fire`
|
||||
--> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:54:32
|
||||
|
|
||||
LL | let LovelyAmbition { lips, fire } = the_spirit;
|
||||
| ^^^^ help: try ignoring the field: `fire: _`
|
||||
|
||||
warning: unused variable: `case`
|
||||
--> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:54:23
|
||||
--> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:63:23
|
||||
|
|
||||
LL | Large::Suit { case } => {}
|
||||
| ^^^^ help: try ignoring the field: `case: _`
|
||||
|
||||
warning: unused variable: `case`
|
||||
--> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:59:24
|
||||
--> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:68:24
|
||||
|
|
||||
LL | &Large::Suit { case } => {}
|
||||
| ^^^^ help: try ignoring the field: `case: _`
|
||||
|
||||
warning: unused variable: `case`
|
||||
--> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:64:27
|
||||
--> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:73:27
|
||||
|
|
||||
LL | box Large::Suit { case } => {}
|
||||
| ^^^^ help: try ignoring the field: `case: _`
|
||||
|
||||
warning: unused variable: `case`
|
||||
--> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:69:24
|
||||
--> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:78:24
|
||||
|
|
||||
LL | (Large::Suit { case },) => {}
|
||||
| ^^^^ help: try ignoring the field: `case: _`
|
||||
|
||||
warning: unused variable: `case`
|
||||
--> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:74:24
|
||||
--> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:83:24
|
||||
|
|
||||
LL | [Large::Suit { case }] => {}
|
||||
| ^^^^ help: try ignoring the field: `case: _`
|
||||
|
||||
warning: unused variable: `case`
|
||||
--> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:79:29
|
||||
--> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:88:29
|
||||
|
|
||||
LL | Tuple(Large::Suit { case }, ()) => {}
|
||||
| ^^^^ help: try ignoring the field: `case: _`
|
||||
|
||||
warning: variable does not need to be mutable
|
||||
--> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:38:9
|
||||
--> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:43:9
|
||||
|
|
||||
LL | let mut mut_unused_var = 1;
|
||||
| ----^^^^^^^^^^^^^^
|
||||
|
|
@ -108,7 +114,7 @@ LL | #![warn(unused)] // UI tests pass `-A unused` (#43896)
|
|||
= note: #[warn(unused_mut)] implied by #[warn(unused)]
|
||||
|
||||
warning: variable does not need to be mutable
|
||||
--> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:40:10
|
||||
--> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:45:10
|
||||
|
|
||||
LL | let (mut var, unused_var) = (1, 2);
|
||||
| ----^^^
|
||||
|
|
|
|||
Loading…
Add table
Add a link
Reference in a new issue