diff --git a/src/librustc/middle/liveness.rs b/src/librustc/middle/liveness.rs index 17c114bc3b3c0..d1a46f5f15563 100644 --- a/src/librustc/middle/liveness.rs +++ b/src/librustc/middle/liveness.rs @@ -111,6 +111,7 @@ use ty::{self, TyCtxt}; use lint; use util::nodemap::{NodeMap, NodeSet}; +use std::collections::VecDeque; use std::{fmt, usize}; use std::io::prelude::*; use std::io; @@ -412,18 +413,43 @@ fn visit_local<'a, 'tcx>(ir: &mut IrMaps<'a, 'tcx>, local: &'tcx hir::Local) { } fn visit_arm<'a, 'tcx>(ir: &mut IrMaps<'a, 'tcx>, arm: &'tcx hir::Arm) { - for pat in &arm.pats { - // for struct patterns, take note of which fields used shorthand (`x` rather than `x: x`) + 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`. + // 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(); - if let hir::PatKind::Struct(_, ref fields, _) = pat.node { - for field in fields { - if field.node.is_shorthand { - shorthand_field_ids.insert(field.node.pat.id); + 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()); + } + _ => {} } } diff --git a/src/test/ui/lint/issue-47390-unused-variable-in-struct-pattern.rs b/src/test/ui/lint/issue-47390-unused-variable-in-struct-pattern.rs index 18b83370355b6..6994a377a06d7 100644 --- a/src/test/ui/lint/issue-47390-unused-variable-in-struct-pattern.rs +++ b/src/test/ui/lint/issue-47390-unused-variable-in-struct-pattern.rs @@ -10,6 +10,8 @@ // compile-pass +#![feature(box_syntax)] +#![feature(box_patterns)] #![warn(unused)] // UI tests pass `-A unused` (#43896) struct SoulHistory { @@ -18,6 +20,13 @@ struct SoulHistory { endless_and_singing: bool } +#[derive(Clone, Copy)] +enum Large { + Suit { case: () } +} + +struct Tuple(Large, ()); + fn main() { let i_think_continually = 2; let who_from_the_womb_remembered = SoulHistory { @@ -31,4 +40,38 @@ fn main() { endless_and_singing: true } = who_from_the_womb_remembered { hours_are_suns = false; } + + let bag = Large::Suit { + case: () + }; + + // Plain struct + match bag { + Large::Suit { case } => {} + }; + + // Referenced struct + match &bag { + &Large::Suit { case } => {} + }; + + // Boxed struct + match box bag { + box Large::Suit { case } => {} + }; + + // Tuple with struct + match (bag,) { + (Large::Suit { case },) => {} + }; + + // Slice with struct + match [bag] { + [Large::Suit { case }] => {} + }; + + // Tuple struct with struct + match Tuple(bag, ()) { + Tuple(Large::Suit { case }, ()) => {} + }; } diff --git a/src/test/ui/lint/issue-47390-unused-variable-in-struct-pattern.stderr b/src/test/ui/lint/issue-47390-unused-variable-in-struct-pattern.stderr index 35fe5479406df..7bfe2c9162ed1 100644 --- a/src/test/ui/lint/issue-47390-unused-variable-in-struct-pattern.stderr +++ b/src/test/ui/lint/issue-47390-unused-variable-in-struct-pattern.stderr @@ -1,24 +1,24 @@ warning: unused variable: `i_think_continually` - --> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:22:9 + --> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:31:9 | LL | let i_think_continually = 2; | ^^^^^^^^^^^^^^^^^^^ help: consider using `_i_think_continually` instead | note: lint level defined here - --> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:13:9 + --> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:15:9 | LL | #![warn(unused)] // UI tests pass `-A unused` (#43896) | ^^^^^^ = note: #[warn(unused_variables)] implied by #[warn(unused)] warning: unused variable: `corridors_of_light` - --> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:29:26 + --> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:38:26 | 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:30:26 + --> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:39:26 | LL | mut hours_are_suns, | ^^^^^^^^^^^^^^^^^^ @@ -26,15 +26,51 @@ 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:32:9 + --> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:41:9 | LL | hours_are_suns = false; | ^^^^^^^^^^^^^^ | note: lint level defined here - --> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:13:9 + --> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:15:9 | LL | #![warn(unused)] // UI tests pass `-A unused` (#43896) | ^^^^^^ = note: #[warn(unused_assignments)] implied by #[warn(unused)] +warning: unused variable: `case` + --> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:50:23 + | +LL | Large::Suit { case } => {} + | ^^^^ help: try ignoring the field: `case: _` + +warning: unused variable: `case` + --> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:55:24 + | +LL | &Large::Suit { case } => {} + | ^^^^ help: try ignoring the field: `case: _` + +warning: unused variable: `case` + --> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:60:27 + | +LL | box Large::Suit { case } => {} + | ^^^^ help: try ignoring the field: `case: _` + +warning: unused variable: `case` + --> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:65:24 + | +LL | (Large::Suit { case },) => {} + | ^^^^ help: try ignoring the field: `case: _` + +warning: unused variable: `case` + --> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:70:24 + | +LL | [Large::Suit { case }] => {} + | ^^^^ help: try ignoring the field: `case: _` + +warning: unused variable: `case` + --> $DIR/issue-47390-unused-variable-in-struct-pattern.rs:75:29 + | +LL | Tuple(Large::Suit { case }, ()) => {} + | ^^^^ help: try ignoring the field: `case: _` +