unused_parens: fix for or-patterns + &(mut x)
This commit is contained in:
Mazdak Farrokhzad
parent
b50520835f
commit
e85b181638
@ -398,18 +398,37 @@ impl UnusedParens {
|
||||
}
|
||||
}
|
||||
|
||||
fn check_unused_parens_pat(&self,
|
||||
cx: &EarlyContext<'_>,
|
||||
value: &ast::Pat,
|
||||
msg: &str) {
|
||||
if let ast::PatKind::Paren(_) = value.node {
|
||||
fn check_unused_parens_pat(
|
||||
&self,
|
||||
cx: &EarlyContext<'_>,
|
||||
value: &ast::Pat,
|
||||
avoid_or: bool,
|
||||
avoid_mut: bool,
|
||||
) {
|
||||
use ast::{PatKind, BindingMode::ByValue, Mutability::Mutable};
|
||||
|
||||
if let PatKind::Paren(inner) = &value.node {
|
||||
match inner.node {
|
||||
// The lint visitor will visit each subpattern of `p`. We do not want to lint
|
||||
// any range pattern no matter where it occurs in the pattern. For something like
|
||||
// `&(a..=b)`, there is a recursive `check_pat` on `a` and `b`, but we will assume
|
||||
// that if there are unnecessary parens they serve a purpose of readability.
|
||||
PatKind::Range(..) => return,
|
||||
// Avoid `p0 | .. | pn` if we should.
|
||||
PatKind::Or(..) if avoid_or => return,
|
||||
// Avoid `mut x` and `mut x @ p` if we should:
|
||||
PatKind::Ident(ByValue(Mutable), ..) if avoid_mut => return,
|
||||
// Otherwise proceed with linting.
|
||||
_ => {}
|
||||
}
|
||||
|
||||
let pattern_text = if let Ok(snippet) = cx.sess().source_map()
|
||||
.span_to_snippet(value.span) {
|
||||
snippet
|
||||
} else {
|
||||
pprust::pat_to_string(value)
|
||||
};
|
||||
Self::remove_outer_parens(cx, value.span, &pattern_text, msg, (false, false));
|
||||
Self::remove_outer_parens(cx, value.span, &pattern_text, "pattern", (false, false));
|
||||
}
|
||||
}
|
||||
|
||||
@ -474,6 +493,13 @@ impl EarlyLintPass for UnusedParens {
|
||||
fn check_expr(&mut self, cx: &EarlyContext<'_>, e: &ast::Expr) {
|
||||
use syntax::ast::ExprKind::*;
|
||||
let (value, msg, followed_by_block, left_pos, right_pos) = match e.node {
|
||||
Let(ref pats, ..) => {
|
||||
for p in pats {
|
||||
self.check_unused_parens_pat(cx, p, false, false);
|
||||
}
|
||||
return;
|
||||
}
|
||||
|
||||
If(ref cond, ref block, ..) => {
|
||||
let left = e.span.lo() + syntax_pos::BytePos(2);
|
||||
let right = block.span.lo();
|
||||
@ -486,7 +512,8 @@ impl EarlyLintPass for UnusedParens {
|
||||
(cond, "`while` condition", true, Some(left), Some(right))
|
||||
},
|
||||
|
||||
ForLoop(_, ref cond, ref block, ..) => {
|
||||
ForLoop(ref pat, ref cond, ref block, ..) => {
|
||||
self.check_unused_parens_pat(cx, pat, false, false);
|
||||
(cond, "`for` head expression", true, None, Some(block.span.lo()))
|
||||
}
|
||||
|
||||
@ -531,26 +558,46 @@ impl EarlyLintPass for UnusedParens {
|
||||
}
|
||||
|
||||
fn check_pat(&mut self, cx: &EarlyContext<'_>, p: &ast::Pat) {
|
||||
use ast::PatKind::{Paren, Range};
|
||||
// The lint visitor will visit each subpattern of `p`. We do not want to lint any range
|
||||
// pattern no matter where it occurs in the pattern. For something like `&(a..=b)`, there
|
||||
// is a recursive `check_pat` on `a` and `b`, but we will assume that if there are
|
||||
// unnecessary parens they serve a purpose of readability.
|
||||
if let Paren(ref pat) = p.node {
|
||||
match pat.node {
|
||||
Range(..) => {}
|
||||
_ => self.check_unused_parens_pat(cx, &p, "pattern")
|
||||
}
|
||||
use ast::{PatKind::*, Mutability};
|
||||
match &p.node {
|
||||
// Do not lint on `(..)` as that will result in the other arms being useless.
|
||||
Paren(_)
|
||||
// The other cases do not contain sub-patterns.
|
||||
| Wild | Rest | Lit(..) | Mac(..) | Range(..) | Ident(.., None) | Path(..) => return,
|
||||
// These are list-like patterns; parens can always be removed.
|
||||
TupleStruct(_, ps) | Tuple(ps) | Slice(ps) | Or(ps) => for p in ps {
|
||||
self.check_unused_parens_pat(cx, p, false, false);
|
||||
},
|
||||
Struct(_, fps, _) => for f in fps {
|
||||
self.check_unused_parens_pat(cx, &f.pat, false, false);
|
||||
},
|
||||
// Avoid linting on `i @ (p0 | .. | pn)` and `box (p0 | .. | pn)`, #64106.
|
||||
Ident(.., Some(p)) | Box(p) => self.check_unused_parens_pat(cx, p, true, false),
|
||||
// Avoid linting on `&(mut x)` as `&mut x` has a different meaning, #55342.
|
||||
// Also avoid linting on `& mut? (p0 | .. | pn)`, #64106.
|
||||
Ref(p, m) => self.check_unused_parens_pat(cx, p, true, *m == Mutability::Immutable),
|
||||
}
|
||||
}
|
||||
|
||||
fn check_stmt(&mut self, cx: &EarlyContext<'_>, s: &ast::Stmt) {
|
||||
if let ast::StmtKind::Local(ref local) = s.node {
|
||||
self.check_unused_parens_pat(cx, &local.pat, false, false);
|
||||
|
||||
if let Some(ref value) = local.init {
|
||||
self.check_unused_parens_expr(cx, &value, "assigned value", false, None, None);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
fn check_param(&mut self, cx: &EarlyContext<'_>, param: &ast::Param) {
|
||||
self.check_unused_parens_pat(cx, ¶m.pat, true, false);
|
||||
}
|
||||
|
||||
fn check_arm(&mut self, cx: &EarlyContext<'_>, arm: &ast::Arm) {
|
||||
for p in &arm.pats {
|
||||
self.check_unused_parens_pat(cx, p, false, false);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
declare_lint! {
|
||||
|
||||
@ -1,25 +1,75 @@
|
||||
// build-pass (FIXME(62277): could be check-pass?)
|
||||
#![feature(box_patterns)]
|
||||
|
||||
#![feature(or_patterns)]
|
||||
//~^ WARN the feature `or_patterns` is incomplete
|
||||
|
||||
#![allow(ellipsis_inclusive_range_patterns)]
|
||||
#![allow(unreachable_patterns)]
|
||||
#![allow(unused_variables)]
|
||||
#![warn(unused_parens)]
|
||||
#![deny(unused_parens)]
|
||||
|
||||
fn lint_on_top_level() {
|
||||
let (a) = 0; //~ ERROR unnecessary parentheses around pattern
|
||||
for (a) in 0..1 {} //~ ERROR unnecessary parentheses around pattern
|
||||
if let (a) = 0 {} //~ ERROR unnecessary parentheses around pattern
|
||||
while let (a) = 0 {} //~ ERROR unnecessary parentheses around pattern
|
||||
fn foo((a): u8) {} //~ ERROR unnecessary parentheses around pattern
|
||||
let _ = |(a): u8| 0; //~ ERROR unnecessary parentheses around pattern
|
||||
}
|
||||
|
||||
// Don't lint in these cases (#64106).
|
||||
fn or_patterns_no_lint() {
|
||||
match Box::new(0) {
|
||||
box (0 | 1) => {} // Should not lint as `box 0 | 1` binds as `(box 0) | 1`.
|
||||
_ => {}
|
||||
}
|
||||
|
||||
match 0 {
|
||||
x @ (0 | 1) => {} // Should not lint as `x @ 0 | 1` binds as `(x @ 0) | 1`.
|
||||
_ => {}
|
||||
}
|
||||
|
||||
if let &(0 | 1) = &0 {} // Should also not lint.
|
||||
if let &mut (0 | 1) = &mut 0 {} // Same.
|
||||
|
||||
fn foo((Ok(a) | Err(a)): Result<u8, u8>) {} // Doesn't parse if we remove parens for now.
|
||||
//~^ ERROR identifier `a` is bound more than once
|
||||
|
||||
let _ = |(Ok(a) | Err(a)): Result<u8, u8>| 1; // `|Ok(a) | Err(a)| 1` parses as bit-or.
|
||||
//~^ ERROR identifier `a` is bound more than once
|
||||
}
|
||||
|
||||
fn or_patterns_will_lint() {
|
||||
if let (0 | 1) = 0 {} //~ ERROR unnecessary parentheses around pattern
|
||||
if let ((0 | 1),) = (0,) {} //~ ERROR unnecessary parentheses around pattern
|
||||
if let [(0 | 1)] = [0] {} //~ ERROR unnecessary parentheses around pattern
|
||||
if let 0 | (1 | 2) = 0 {} //~ ERROR unnecessary parentheses around pattern
|
||||
struct TS(u8);
|
||||
if let TS((0 | 1)) = TS(0) {} //~ ERROR unnecessary parentheses around pattern
|
||||
struct NS { f: u8 }
|
||||
if let NS { f: (0 | 1) } = (NS { f: 0 }) {} //~ ERROR unnecessary parentheses around pattern
|
||||
}
|
||||
|
||||
// Don't lint on `&(mut x)` because `&mut x` means something else (#55342).
|
||||
fn deref_mut_binding_no_lint() {
|
||||
let &(mut x) = &0;
|
||||
}
|
||||
|
||||
fn main() {
|
||||
match 1 {
|
||||
(_) => {} //~ WARNING: unnecessary parentheses around pattern
|
||||
(y) => {} //~ WARNING: unnecessary parentheses around pattern
|
||||
(ref r) => {} //~ WARNING: unnecessary parentheses around pattern
|
||||
(e @ 1...2) => {} //~ WARNING: unnecessary parentheses around outer pattern
|
||||
(1...2) => {} // Non ambiguous range pattern should not warn
|
||||
(_) => {} //~ ERROR unnecessary parentheses around pattern
|
||||
(y) => {} //~ ERROR unnecessary parentheses around pattern
|
||||
(ref r) => {} //~ ERROR unnecessary parentheses around pattern
|
||||
(e @ 1...2) => {} //~ ERROR unnecessary parentheses around pattern
|
||||
(1...2) => {} // Non ambiguous range pattern should not warn
|
||||
e @ (3...4) => {} // Non ambiguous range pattern should not warn
|
||||
}
|
||||
|
||||
match &1 {
|
||||
(e @ &(1...2)) => {} //~ WARNING: unnecessary parentheses around outer pattern
|
||||
&(_) => {} //~ WARNING: unnecessary parentheses around pattern
|
||||
e @ &(1...2) => {} // Ambiguous range pattern should not warn
|
||||
&(1...2) => {} // Ambiguous range pattern should not warn
|
||||
(e @ &(1...2)) => {} //~ ERROR unnecessary parentheses around pattern
|
||||
&(_) => {} //~ ERROR unnecessary parentheses around pattern
|
||||
e @ &(1...2) => {} // Ambiguous range pattern should not warn
|
||||
&(1...2) => {} // Ambiguous range pattern should not warn
|
||||
}
|
||||
|
||||
match &1 {
|
||||
@ -28,19 +78,19 @@ fn main() {
|
||||
}
|
||||
|
||||
match 1 {
|
||||
(_) => {} //~ WARNING: unnecessary parentheses around pattern
|
||||
(y) => {} //~ WARNING: unnecessary parentheses around pattern
|
||||
(ref r) => {} //~ WARNING: unnecessary parentheses around pattern
|
||||
(e @ 1..=2) => {} //~ WARNING: unnecessary parentheses around outer pattern
|
||||
(1..=2) => {} // Non ambiguous range pattern should not warn
|
||||
(_) => {} //~ ERROR unnecessary parentheses around pattern
|
||||
(y) => {} //~ ERROR unnecessary parentheses around pattern
|
||||
(ref r) => {} //~ ERROR unnecessary parentheses around pattern
|
||||
(e @ 1..=2) => {} //~ ERROR unnecessary parentheses around pattern
|
||||
(1..=2) => {} // Non ambiguous range pattern should not warn
|
||||
e @ (3..=4) => {} // Non ambiguous range pattern should not warn
|
||||
}
|
||||
|
||||
match &1 {
|
||||
(e @ &(1..=2)) => {} //~ WARNING: unnecessary parentheses around outer pattern
|
||||
&(_) => {} //~ WARNING: unnecessary parentheses around pattern
|
||||
e @ &(1..=2) => {} // Ambiguous range pattern should not warn
|
||||
&(1..=2) => {} // Ambiguous range pattern should not warn
|
||||
(e @ &(1..=2)) => {} //~ ERROR unnecessary parentheses around pattern
|
||||
&(_) => {} //~ ERROR unnecessary parentheses around pattern
|
||||
e @ &(1..=2) => {} // Ambiguous range pattern should not warn
|
||||
&(1..=2) => {} // Ambiguous range pattern should not warn
|
||||
}
|
||||
|
||||
match &1 {
|
||||
|
||||
@ -1,78 +1,173 @@
|
||||
warning: unnecessary parentheses around pattern
|
||||
--> $DIR/issue-54538-unused-parens-lint.rs:10:9
|
||||
error[E0416]: identifier `a` is bound more than once in the same pattern
|
||||
--> $DIR/issue-54538-unused-parens-lint.rs:35:25
|
||||
|
|
||||
LL | (_) => {}
|
||||
LL | fn foo((Ok(a) | Err(a)): Result<u8, u8>) {} // Doesn't parse if we remove parens for now.
|
||||
| ^ used in a pattern more than once
|
||||
|
||||
error[E0416]: identifier `a` is bound more than once in the same pattern
|
||||
--> $DIR/issue-54538-unused-parens-lint.rs:38:27
|
||||
|
|
||||
LL | let _ = |(Ok(a) | Err(a)): Result<u8, u8>| 1; // `|Ok(a) | Err(a)| 1` parses as bit-or.
|
||||
| ^ used in a pattern more than once
|
||||
|
||||
warning: the feature `or_patterns` is incomplete and may cause the compiler to crash
|
||||
--> $DIR/issue-54538-unused-parens-lint.rs:3:12
|
||||
|
|
||||
LL | #![feature(or_patterns)]
|
||||
| ^^^^^^^^^^^
|
||||
|
|
||||
= note: `#[warn(incomplete_features)]` on by default
|
||||
|
||||
error: unnecessary parentheses around pattern
|
||||
--> $DIR/issue-54538-unused-parens-lint.rs:12:9
|
||||
|
|
||||
LL | let (a) = 0;
|
||||
| ^^^ help: remove these parentheses
|
||||
|
|
||||
note: lint level defined here
|
||||
--> $DIR/issue-54538-unused-parens-lint.rs:6:9
|
||||
--> $DIR/issue-54538-unused-parens-lint.rs:9:9
|
||||
|
|
||||
LL | #![warn(unused_parens)]
|
||||
LL | #![deny(unused_parens)]
|
||||
| ^^^^^^^^^^^^^
|
||||
|
||||
warning: unnecessary parentheses around pattern
|
||||
--> $DIR/issue-54538-unused-parens-lint.rs:11:9
|
||||
error: unnecessary parentheses around pattern
|
||||
--> $DIR/issue-54538-unused-parens-lint.rs:13:9
|
||||
|
|
||||
LL | for (a) in 0..1 {}
|
||||
| ^^^ help: remove these parentheses
|
||||
|
||||
error: unnecessary parentheses around pattern
|
||||
--> $DIR/issue-54538-unused-parens-lint.rs:14:12
|
||||
|
|
||||
LL | if let (a) = 0 {}
|
||||
| ^^^ help: remove these parentheses
|
||||
|
||||
error: unnecessary parentheses around pattern
|
||||
--> $DIR/issue-54538-unused-parens-lint.rs:15:15
|
||||
|
|
||||
LL | while let (a) = 0 {}
|
||||
| ^^^ help: remove these parentheses
|
||||
|
||||
error: unnecessary parentheses around pattern
|
||||
--> $DIR/issue-54538-unused-parens-lint.rs:16:12
|
||||
|
|
||||
LL | fn foo((a): u8) {}
|
||||
| ^^^ help: remove these parentheses
|
||||
|
||||
error: unnecessary parentheses around pattern
|
||||
--> $DIR/issue-54538-unused-parens-lint.rs:17:14
|
||||
|
|
||||
LL | let _ = |(a): u8| 0;
|
||||
| ^^^ help: remove these parentheses
|
||||
|
||||
error: unnecessary parentheses around pattern
|
||||
--> $DIR/issue-54538-unused-parens-lint.rs:43:12
|
||||
|
|
||||
LL | if let (0 | 1) = 0 {}
|
||||
| ^^^^^^^ help: remove these parentheses
|
||||
|
||||
error: unnecessary parentheses around pattern
|
||||
--> $DIR/issue-54538-unused-parens-lint.rs:44:13
|
||||
|
|
||||
LL | if let ((0 | 1),) = (0,) {}
|
||||
| ^^^^^^^ help: remove these parentheses
|
||||
|
||||
error: unnecessary parentheses around pattern
|
||||
--> $DIR/issue-54538-unused-parens-lint.rs:45:13
|
||||
|
|
||||
LL | if let [(0 | 1)] = [0] {}
|
||||
| ^^^^^^^ help: remove these parentheses
|
||||
|
||||
error: unnecessary parentheses around pattern
|
||||
--> $DIR/issue-54538-unused-parens-lint.rs:46:16
|
||||
|
|
||||
LL | if let 0 | (1 | 2) = 0 {}
|
||||
| ^^^^^^^ help: remove these parentheses
|
||||
|
||||
error: unnecessary parentheses around pattern
|
||||
--> $DIR/issue-54538-unused-parens-lint.rs:48:15
|
||||
|
|
||||
LL | if let TS((0 | 1)) = TS(0) {}
|
||||
| ^^^^^^^ help: remove these parentheses
|
||||
|
||||
error: unnecessary parentheses around pattern
|
||||
--> $DIR/issue-54538-unused-parens-lint.rs:50:20
|
||||
|
|
||||
LL | if let NS { f: (0 | 1) } = (NS { f: 0 }) {}
|
||||
| ^^^^^^^ help: remove these parentheses
|
||||
|
||||
error: unnecessary parentheses around pattern
|
||||
--> $DIR/issue-54538-unused-parens-lint.rs:60:9
|
||||
|
|
||||
LL | (_) => {}
|
||||
| ^^^ help: remove these parentheses
|
||||
|
||||
error: unnecessary parentheses around pattern
|
||||
--> $DIR/issue-54538-unused-parens-lint.rs:61:9
|
||||
|
|
||||
LL | (y) => {}
|
||||
| ^^^ help: remove these parentheses
|
||||
|
||||
warning: unnecessary parentheses around pattern
|
||||
--> $DIR/issue-54538-unused-parens-lint.rs:12:9
|
||||
error: unnecessary parentheses around pattern
|
||||
--> $DIR/issue-54538-unused-parens-lint.rs:62:9
|
||||
|
|
||||
LL | (ref r) => {}
|
||||
| ^^^^^^^ help: remove these parentheses
|
||||
|
||||
warning: unnecessary parentheses around pattern
|
||||
--> $DIR/issue-54538-unused-parens-lint.rs:13:9
|
||||
error: unnecessary parentheses around pattern
|
||||
--> $DIR/issue-54538-unused-parens-lint.rs:63:9
|
||||
|
|
||||
LL | (e @ 1...2) => {}
|
||||
| ^^^^^^^^^^^ help: remove these parentheses
|
||||
|
||||
warning: unnecessary parentheses around pattern
|
||||
--> $DIR/issue-54538-unused-parens-lint.rs:19:9
|
||||
error: unnecessary parentheses around pattern
|
||||
--> $DIR/issue-54538-unused-parens-lint.rs:69:9
|
||||
|
|
||||
LL | (e @ &(1...2)) => {}
|
||||
| ^^^^^^^^^^^^^^ help: remove these parentheses
|
||||
|
||||
warning: unnecessary parentheses around pattern
|
||||
--> $DIR/issue-54538-unused-parens-lint.rs:20:10
|
||||
error: unnecessary parentheses around pattern
|
||||
--> $DIR/issue-54538-unused-parens-lint.rs:70:10
|
||||
|
|
||||
LL | &(_) => {}
|
||||
| ^^^ help: remove these parentheses
|
||||
|
||||
warning: unnecessary parentheses around pattern
|
||||
--> $DIR/issue-54538-unused-parens-lint.rs:31:9
|
||||
error: unnecessary parentheses around pattern
|
||||
--> $DIR/issue-54538-unused-parens-lint.rs:81:9
|
||||
|
|
||||
LL | (_) => {}
|
||||
| ^^^ help: remove these parentheses
|
||||
|
||||
warning: unnecessary parentheses around pattern
|
||||
--> $DIR/issue-54538-unused-parens-lint.rs:32:9
|
||||
error: unnecessary parentheses around pattern
|
||||
--> $DIR/issue-54538-unused-parens-lint.rs:82:9
|
||||
|
|
||||
LL | (y) => {}
|
||||
| ^^^ help: remove these parentheses
|
||||
|
||||
warning: unnecessary parentheses around pattern
|
||||
--> $DIR/issue-54538-unused-parens-lint.rs:33:9
|
||||
error: unnecessary parentheses around pattern
|
||||
--> $DIR/issue-54538-unused-parens-lint.rs:83:9
|
||||
|
|
||||
LL | (ref r) => {}
|
||||
| ^^^^^^^ help: remove these parentheses
|
||||
|
||||
warning: unnecessary parentheses around pattern
|
||||
--> $DIR/issue-54538-unused-parens-lint.rs:34:9
|
||||
error: unnecessary parentheses around pattern
|
||||
--> $DIR/issue-54538-unused-parens-lint.rs:84:9
|
||||
|
|
||||
LL | (e @ 1..=2) => {}
|
||||
| ^^^^^^^^^^^ help: remove these parentheses
|
||||
|
||||
warning: unnecessary parentheses around pattern
|
||||
--> $DIR/issue-54538-unused-parens-lint.rs:40:9
|
||||
error: unnecessary parentheses around pattern
|
||||
--> $DIR/issue-54538-unused-parens-lint.rs:90:9
|
||||
|
|
||||
LL | (e @ &(1..=2)) => {}
|
||||
| ^^^^^^^^^^^^^^ help: remove these parentheses
|
||||
|
||||
warning: unnecessary parentheses around pattern
|
||||
--> $DIR/issue-54538-unused-parens-lint.rs:41:10
|
||||
error: unnecessary parentheses around pattern
|
||||
--> $DIR/issue-54538-unused-parens-lint.rs:91:10
|
||||
|
|
||||
LL | &(_) => {}
|
||||
| ^^^ help: remove these parentheses
|
||||
|
||||
error: aborting due to 26 previous errors
|
||||
|
||||
For more information about this error, try `rustc --explain E0416`.
|
||||
|
||||
Loading…
x
Reference in New Issue
Block a user