diff --git a/clippy_lints/src/redundant_clone.rs b/clippy_lints/src/redundant_clone.rs
index ad8ed568656..965f6bac62a 100644
--- a/clippy_lints/src/redundant_clone.rs
+++ b/clippy_lints/src/redundant_clone.rs
@@ -208,13 +208,21 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for RedundantClone {
let sugg_span = span.with_lo(
span.lo() + BytePos(u32::try_from(dot).unwrap())
);
+ let mut app = Applicability::MaybeIncorrect;
+ let mut call_snip = &snip[dot + 1..];
+ if call_snip.ends_with("()") {
+ call_snip = call_snip[..call_snip.len()-2].trim();
+ if call_snip.as_bytes().iter().all(|b| b.is_ascii_alphabetic() || *b == b'_') {
+ app = Applicability::MachineApplicable;
+ }
+ }
span_lint_hir_and_then(cx, REDUNDANT_CLONE, node, sugg_span, "redundant clone", |db| {
db.span_suggestion(
sugg_span,
"remove this",
String::new(),
- Applicability::MaybeIncorrect,
+ app,
);
db.span_note(
span.with_hi(span.lo() + BytePos(u32::try_from(dot).unwrap())),
diff --git a/tests/ui/redundant_clone.fixed b/tests/ui/redundant_clone.fixed
new file mode 100644
index 00000000000..614a9bf4d90
--- /dev/null
+++ b/tests/ui/redundant_clone.fixed
@@ -0,0 +1,132 @@
+// run-rustfix
+// rustfix-only-machine-applicable
+use std::ffi::OsString;
+use std::path::Path;
+
+fn main() {
+ let _s = ["lorem", "ipsum"].join(" ");
+
+ let s = String::from("foo");
+ let _s = s;
+
+ let s = String::from("foo");
+ let _s = s;
+
+ let s = String::from("foo");
+ let _s = s;
+
+ let _s = Path::new("/a/b/").join("c");
+
+ let _s = Path::new("/a/b/").join("c");
+
+ let _s = OsString::new();
+
+ let _s = OsString::new();
+
+ // Check that lint level works
+ #[allow(clippy::redundant_clone)]
+ let _s = String::new().to_string();
+
+ let tup = (String::from("foo"),);
+ let _t = tup.0;
+
+ let tup_ref = &(String::from("foo"),);
+ let _s = tup_ref.0.clone(); // this `.clone()` cannot be removed
+
+ {
+ let x = String::new();
+ let y = &x;
+
+ let _x = x.clone(); // ok; `x` is borrowed by `y`
+
+ let _ = y.len();
+ }
+
+ let x = (String::new(),);
+ let _ = Some(String::new()).unwrap_or_else(|| x.0.clone()); // ok; closure borrows `x`
+
+ with_branch(Alpha, true);
+ cannot_move_from_type_with_drop();
+ borrower_propagation();
+}
+
+#[derive(Clone)]
+struct Alpha;
+fn with_branch(a: Alpha, b: bool) -> (Alpha, Alpha) {
+ if b {
+ (a.clone(), a)
+ } else {
+ (Alpha, a)
+ }
+}
+
+struct TypeWithDrop {
+ x: String,
+}
+
+impl Drop for TypeWithDrop {
+ fn drop(&mut self) {}
+}
+
+fn cannot_move_from_type_with_drop() -> String {
+ let s = TypeWithDrop { x: String::new() };
+ s.x.clone() // removing this `clone()` summons E0509
+}
+
+fn borrower_propagation() {
+ let s = String::new();
+ let t = String::new();
+
+ {
+ fn b() -> bool {
+ unimplemented!()
+ }
+ let _u = if b() { &s } else { &t };
+
+ // ok; `s` and `t` are possibly borrowed
+ let _s = s.clone();
+ let _t = t.clone();
+ }
+
+ {
+ let _u = || s.len();
+ let _v = [&t; 32];
+ let _s = s.clone(); // ok
+ let _t = t.clone(); // ok
+ }
+
+ {
+ let _u = {
+ let u = Some(&s);
+ let _ = s.clone(); // ok
+ u
+ };
+ let _s = s.clone(); // ok
+ }
+
+ {
+ use std::convert::identity as id;
+ let _u = id(id(&s));
+ let _s = s.clone(); // ok, `u` borrows `s`
+ }
+
+ let _s = s;
+ let _t = t;
+
+ #[derive(Clone)]
+ struct Foo {
+ x: usize,
+ }
+
+ {
+ let f = Foo { x: 123 };
+ let _x = Some(f.x);
+ let _f = f;
+ }
+
+ {
+ let f = Foo { x: 123 };
+ let _x = &f.x;
+ let _f = f.clone(); // ok
+ }
+}
diff --git a/tests/ui/redundant_clone.rs b/tests/ui/redundant_clone.rs
index 4e38a5c924c..48687c82c2f 100644
--- a/tests/ui/redundant_clone.rs
+++ b/tests/ui/redundant_clone.rs
@@ -1,34 +1,34 @@
-#![warn(clippy::redundant_clone)]
-
+// run-rustfix
+// rustfix-only-machine-applicable
use std::ffi::OsString;
use std::path::Path;
fn main() {
- let _ = ["lorem", "ipsum"].join(" ").to_string();
+ let _s = ["lorem", "ipsum"].join(" ").to_string();
let s = String::from("foo");
- let _ = s.clone();
+ let _s = s.clone();
let s = String::from("foo");
- let _ = s.to_string();
+ let _s = s.to_string();
let s = String::from("foo");
- let _ = s.to_owned();
+ let _s = s.to_owned();
- let _ = Path::new("/a/b/").join("c").to_owned();
+ let _s = Path::new("/a/b/").join("c").to_owned();
- let _ = Path::new("/a/b/").join("c").to_path_buf();
+ let _s = Path::new("/a/b/").join("c").to_path_buf();
- let _ = OsString::new().to_owned();
+ let _s = OsString::new().to_owned();
- let _ = OsString::new().to_os_string();
+ let _s = OsString::new().to_os_string();
// Check that lint level works
#[allow(clippy::redundant_clone)]
- let _ = String::new().to_string();
+ let _s = String::new().to_string();
let tup = (String::from("foo"),);
- let _ = tup.0.clone();
+ let _t = tup.0.clone();
let tup_ref = &(String::from("foo"),);
let _s = tup_ref.0.clone(); // this `.clone()` cannot be removed
@@ -37,13 +37,17 @@ fn main() {
let x = String::new();
let y = &x;
- let _ = x.clone(); // ok; `x` is borrowed by `y`
+ let _x = x.clone(); // ok; `x` is borrowed by `y`
let _ = y.len();
}
let x = (String::new(),);
let _ = Some(String::new()).unwrap_or_else(|| x.0.clone()); // ok; closure borrows `x`
+
+ with_branch(Alpha, true);
+ cannot_move_from_type_with_drop();
+ borrower_propagation();
}
#[derive(Clone)]
@@ -77,37 +81,37 @@ fn borrower_propagation() {
fn b() -> bool {
unimplemented!()
}
- let u = if b() { &s } else { &t };
+ let _u = if b() { &s } else { &t };
// ok; `s` and `t` are possibly borrowed
- let _ = s.clone();
- let _ = t.clone();
+ let _s = s.clone();
+ let _t = t.clone();
}
{
- let u = || s.len();
- let v = [&t; 32];
- let _ = s.clone(); // ok
- let _ = t.clone(); // ok
+ let _u = || s.len();
+ let _v = [&t; 32];
+ let _s = s.clone(); // ok
+ let _t = t.clone(); // ok
}
{
- let u = {
+ let _u = {
let u = Some(&s);
let _ = s.clone(); // ok
u
};
- let _ = s.clone(); // ok
+ let _s = s.clone(); // ok
}
{
use std::convert::identity as id;
- let u = id(id(&s));
- let _ = s.clone(); // ok, `u` borrows `s`
+ let _u = id(id(&s));
+ let _s = s.clone(); // ok, `u` borrows `s`
}
- let _ = s.clone();
- let _ = t.clone();
+ let _s = s.clone();
+ let _t = t.clone();
#[derive(Clone)]
struct Foo {
diff --git a/tests/ui/redundant_clone.stderr b/tests/ui/redundant_clone.stderr
index d1bc7e44fda..feafbd78b4e 100644
--- a/tests/ui/redundant_clone.stderr
+++ b/tests/ui/redundant_clone.stderr
@@ -1,156 +1,156 @@
error: redundant clone
- --> $DIR/redundant_clone.rs:7:41
+ --> $DIR/redundant_clone.rs:7:42
|
-LL | let _ = ["lorem", "ipsum"].join(" ").to_string();
- | ^^^^^^^^^^^^ help: remove this
+LL | let _s = ["lorem", "ipsum"].join(" ").to_string();
+ | ^^^^^^^^^^^^ help: remove this
|
= note: `-D clippy::redundant-clone` implied by `-D warnings`
note: this value is dropped without further use
- --> $DIR/redundant_clone.rs:7:13
+ --> $DIR/redundant_clone.rs:7:14
|
-LL | let _ = ["lorem", "ipsum"].join(" ").to_string();
- | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+LL | let _s = ["lorem", "ipsum"].join(" ").to_string();
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: redundant clone
+ --> $DIR/redundant_clone.rs:10:15
+ |
+LL | let _s = s.clone();
+ | ^^^^^^^^ help: remove this
+ |
+note: this value is dropped without further use
--> $DIR/redundant_clone.rs:10:14
|
-LL | let _ = s.clone();
- | ^^^^^^^^ help: remove this
- |
-note: this value is dropped without further use
- --> $DIR/redundant_clone.rs:10:13
- |
-LL | let _ = s.clone();
- | ^
+LL | let _s = s.clone();
+ | ^
error: redundant clone
+ --> $DIR/redundant_clone.rs:13:15
+ |
+LL | let _s = s.to_string();
+ | ^^^^^^^^^^^^ help: remove this
+ |
+note: this value is dropped without further use
--> $DIR/redundant_clone.rs:13:14
|
-LL | let _ = s.to_string();
- | ^^^^^^^^^^^^ help: remove this
- |
-note: this value is dropped without further use
- --> $DIR/redundant_clone.rs:13:13
- |
-LL | let _ = s.to_string();
- | ^
+LL | let _s = s.to_string();
+ | ^
error: redundant clone
+ --> $DIR/redundant_clone.rs:16:15
+ |
+LL | let _s = s.to_owned();
+ | ^^^^^^^^^^^ help: remove this
+ |
+note: this value is dropped without further use
--> $DIR/redundant_clone.rs:16:14
|
-LL | let _ = s.to_owned();
- | ^^^^^^^^^^^ help: remove this
- |
-note: this value is dropped without further use
- --> $DIR/redundant_clone.rs:16:13
- |
-LL | let _ = s.to_owned();
- | ^
+LL | let _s = s.to_owned();
+ | ^
error: redundant clone
- --> $DIR/redundant_clone.rs:18:41
+ --> $DIR/redundant_clone.rs:18:42
|
-LL | let _ = Path::new("/a/b/").join("c").to_owned();
- | ^^^^^^^^^^^ help: remove this
+LL | let _s = Path::new("/a/b/").join("c").to_owned();
+ | ^^^^^^^^^^^ help: remove this
|
note: this value is dropped without further use
- --> $DIR/redundant_clone.rs:18:13
+ --> $DIR/redundant_clone.rs:18:14
|
-LL | let _ = Path::new("/a/b/").join("c").to_owned();
- | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+LL | let _s = Path::new("/a/b/").join("c").to_owned();
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: redundant clone
- --> $DIR/redundant_clone.rs:20:41
+ --> $DIR/redundant_clone.rs:20:42
|
-LL | let _ = Path::new("/a/b/").join("c").to_path_buf();
- | ^^^^^^^^^^^^^^ help: remove this
+LL | let _s = Path::new("/a/b/").join("c").to_path_buf();
+ | ^^^^^^^^^^^^^^ help: remove this
|
note: this value is dropped without further use
- --> $DIR/redundant_clone.rs:20:13
+ --> $DIR/redundant_clone.rs:20:14
|
-LL | let _ = Path::new("/a/b/").join("c").to_path_buf();
- | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+LL | let _s = Path::new("/a/b/").join("c").to_path_buf();
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: redundant clone
- --> $DIR/redundant_clone.rs:22:28
+ --> $DIR/redundant_clone.rs:22:29
|
-LL | let _ = OsString::new().to_owned();
- | ^^^^^^^^^^^ help: remove this
+LL | let _s = OsString::new().to_owned();
+ | ^^^^^^^^^^^ help: remove this
|
note: this value is dropped without further use
- --> $DIR/redundant_clone.rs:22:13
+ --> $DIR/redundant_clone.rs:22:14
|
-LL | let _ = OsString::new().to_owned();
- | ^^^^^^^^^^^^^^^
+LL | let _s = OsString::new().to_owned();
+ | ^^^^^^^^^^^^^^^
error: redundant clone
- --> $DIR/redundant_clone.rs:24:28
+ --> $DIR/redundant_clone.rs:24:29
|
-LL | let _ = OsString::new().to_os_string();
- | ^^^^^^^^^^^^^^^ help: remove this
+LL | let _s = OsString::new().to_os_string();
+ | ^^^^^^^^^^^^^^^ help: remove this
|
note: this value is dropped without further use
- --> $DIR/redundant_clone.rs:24:13
+ --> $DIR/redundant_clone.rs:24:14
|
-LL | let _ = OsString::new().to_os_string();
- | ^^^^^^^^^^^^^^^
+LL | let _s = OsString::new().to_os_string();
+ | ^^^^^^^^^^^^^^^
error: redundant clone
- --> $DIR/redundant_clone.rs:31:18
+ --> $DIR/redundant_clone.rs:31:19
|
-LL | let _ = tup.0.clone();
- | ^^^^^^^^ help: remove this
+LL | let _t = tup.0.clone();
+ | ^^^^^^^^ help: remove this
|
note: this value is dropped without further use
- --> $DIR/redundant_clone.rs:31:13
+ --> $DIR/redundant_clone.rs:31:14
|
-LL | let _ = tup.0.clone();
- | ^^^^^
+LL | let _t = tup.0.clone();
+ | ^^^^^
error: redundant clone
- --> $DIR/redundant_clone.rs:53:22
+ --> $DIR/redundant_clone.rs:57:22
|
LL | (a.clone(), a.clone())
| ^^^^^^^^ help: remove this
|
note: this value is dropped without further use
- --> $DIR/redundant_clone.rs:53:21
+ --> $DIR/redundant_clone.rs:57:21
|
LL | (a.clone(), a.clone())
| ^
error: redundant clone
- --> $DIR/redundant_clone.rs:109:14
+ --> $DIR/redundant_clone.rs:113:15
|
-LL | let _ = s.clone();
- | ^^^^^^^^ help: remove this
+LL | let _s = s.clone();
+ | ^^^^^^^^ help: remove this
|
note: this value is dropped without further use
- --> $DIR/redundant_clone.rs:109:13
+ --> $DIR/redundant_clone.rs:113:14
|
-LL | let _ = s.clone();
- | ^
+LL | let _s = s.clone();
+ | ^
error: redundant clone
- --> $DIR/redundant_clone.rs:110:14
+ --> $DIR/redundant_clone.rs:114:15
|
-LL | let _ = t.clone();
- | ^^^^^^^^ help: remove this
+LL | let _t = t.clone();
+ | ^^^^^^^^ help: remove this
|
note: this value is dropped without further use
- --> $DIR/redundant_clone.rs:110:13
+ --> $DIR/redundant_clone.rs:114:14
|
-LL | let _ = t.clone();
- | ^
+LL | let _t = t.clone();
+ | ^
error: redundant clone
- --> $DIR/redundant_clone.rs:120:19
+ --> $DIR/redundant_clone.rs:124:19
|
LL | let _f = f.clone();
| ^^^^^^^^ help: remove this
|
note: this value is dropped without further use
- --> $DIR/redundant_clone.rs:120:18
+ --> $DIR/redundant_clone.rs:124:18
|
LL | let _f = f.clone();
| ^