Cleanup: Remove redundant clones.

src/bin/cargo/main.rs

@@ -2,6 +2,7 @@
 #![allow(clippy::too_many_arguments)] // large project
 #![allow(clippy::redundant_closure)] // there's a false positive
 #![warn(clippy::needless_borrow)]
+#![warn(clippy::redundant_clone)]
 
 use std::collections::BTreeSet;
 use std::env;

src/cargo/lib.rs

@@ -15,6 +15,7 @@
 #![allow(clippy::type_complexity)] // there's an exceptionally complex type
 #![allow(clippy::wrong_self_convention)] // perhaps `Rc` should be special-cased in Clippy?
 #![warn(clippy::needless_borrow)]
+#![warn(clippy::redundant_clone)]
 
 use std::fmt;
 

src/cargo/ops/cargo_output_metadata.rs

@@ -42,7 +42,7 @@ fn metadata_no_deps(ws: &Workspace<'_>, _opt: &OutputMetadataOptions) -> CargoRe
         packages: ws.members().cloned().collect(),
         workspace_members: ws.members().map(|pkg| pkg.package_id()).collect(),
         resolve: None,
-        target_directory: ws.target_dir().clone().into_path_unlocked(),
+        target_directory: ws.target_dir().into_path_unlocked(),
         version: VERSION,
         workspace_root: ws.root().to_path_buf(),
     })
@@ -70,7 +70,7 @@ fn metadata_full(ws: &Workspace<'_>, opt: &OutputMetadataOptions) -> CargoResult
             resolve: (packages, resolve),
             root: ws.current_opt().map(|pkg| pkg.package_id()),
         }),
-        target_directory: ws.target_dir().clone().into_path_unlocked(),
+        target_directory: ws.target_dir().into_path_unlocked(),
         version: VERSION,
         workspace_root: ws.root().to_path_buf(),
     })

tests/testsuite/main.rs

@@ -3,6 +3,7 @@
 #![allow(clippy::blacklisted_name)]
 #![allow(clippy::explicit_iter_loop)]
 #![warn(clippy::needless_borrow)]
+#![warn(clippy::redundant_clone)]
 
 #[macro_use]
 mod support;

tests/testsuite/path.rs

@@ -580,7 +580,7 @@ fn override_self() {
         .build();
 
     let p = project();
-    let root = p.root().clone();
+    let root = p.root();
     let p = p
         .file(".cargo/config", &format!("paths = ['{}']", root.display()))
         .file(

tests/testsuite/resolve.rs

@@ -340,7 +340,7 @@ fn public_dependency_skiping() {
         pkg!(("b", "0.2.1") => [dep_req_kind("a", "0.2.0", Kind::Normal, true)]),
         pkg!("c" => [dep("a"),dep("b")]),
     ];
-    let reg = registry(input.clone());
+    let reg = registry(input);
 
     resolve(pkg_id("root"), vec![dep("c")], &reg).unwrap();
 }
@@ -360,7 +360,7 @@ fn public_dependency_skiping_in_backtracking() {
         pkg!("B" => [dep_req_kind("A", ">= 0.0.3", Kind::Normal, true)]),
         pkg!("C" => [dep_req("A", "<= 0.0.4"), dep("B")]),
     ];
-    let reg = registry(input.clone());
+    let reg = registry(input);
 
     resolve(pkg_id("root"), vec![dep("C")], &reg).unwrap();
 }
@@ -886,7 +886,7 @@ fn resolving_with_many_equivalent_backtracking() {
         ]),
     );
 
-    let reg = registry(reglist.clone());
+    let reg = registry(reglist);
 
     let res = resolve(
         pkg_id("root"),
@@ -929,7 +929,7 @@ fn resolving_with_deep_traps() {
         }
     }
 
-    let reg = registry(reglist.clone());
+    let reg = registry(reglist);
 
     let res = resolve(
         pkg_id("root"),
@@ -1011,7 +1011,7 @@ fn resolving_with_constrained_cousins_backtrack() {
         ]),
     );
 
-    let reg = registry(reglist.clone());
+    let reg = registry(reglist);
 
     let res = resolve(
         pkg_id("root"),
@@ -1404,6 +1404,6 @@ fn conflict_store_bug() {
         ]),
     ];
 
-    let reg = registry(input.clone());
+    let reg = registry(input);
     let _ = resolve_and_validated(pkg_id("root"), vec![dep("j")], &reg);
 }

tests/testsuite/support/mod.rs

@@ -518,7 +518,7 @@ pub fn main_file(println: &str, deps: &[&str]) -> String {
     buf.push_str(println);
     buf.push_str("); }\n");
 
-    buf.to_string()
+    buf
 }
 
 trait ErrMsg<T> {

tests/testsuite/support/resolver.rs

@@ -34,12 +34,12 @@ pub fn resolve_and_validated(
     registry: &[Summary],
 ) -> CargoResult<Vec<PackageId>> {
     let resolve = resolve_with_config_raw(pkg, deps, registry, None)?;
-    let mut stack = vec![pkg.clone()];
+    let mut stack = vec![pkg];
     let mut used = HashSet::new();
     let mut links = HashSet::new();
     while let Some(p) = stack.pop() {
         assert!(resolve.contains(&p));
-        if used.insert(p.clone()) {
+        if used.insert(p) {
             // in the tests all `links` crates end in `-sys`
             if p.name().ends_with("-sys") {
                 assert!(links.insert(p.name()));
@@ -48,7 +48,7 @@ pub fn resolve_and_validated(
                 for d in deps {
                     assert!(d.matches_id(dp));
                 }
-                dp.clone()
+                dp
             }));
         }
     }
@@ -99,7 +99,7 @@ pub fn resolve_with_config_raw(
     }
     let mut registry = MyRegistry(registry);
     let summary = Summary::new(
-        pkg.clone(),
+        pkg,
         deps,
         &BTreeMap::<String, Vec<String>>::new(),
         None::<String>,
@@ -146,7 +146,7 @@ pub trait ToPkgId {
 
 impl ToPkgId for PackageId {
     fn to_pkgid(&self) -> PackageId {
-        self.clone()
+        *self
     }
 }