Remove or replace all String::to_string calls

Fix all Clippy’s string_to_string warnings.

Author: mcarton

src/cargo/core/package_id.rs

@@ -151,7 +151,7 @@ impl PackageId {
     pub fn with_precise(&self, precise: Option<String>) -> PackageId {
         PackageId {
             inner: Arc::new(PackageIdInner {
-                name: self.inner.name.to_string(),
+                name: self.inner.name.clone(),
                 version: self.inner.version.clone(),
                 source_id: self.inner.source_id.with_precise(precise),
             }),

src/cargo/core/package_id_spec.rs

@@ -92,12 +92,12 @@ impl PackageIdSpec {
                             } else {
                                 let version = try!(name_or_version.to_semver()
                                                                   .map_err(human));
-                                (path_name.to_string(), Some(version))
+                                (path_name.clone(), Some(version))
                             }
                         }
                     }
                 }
-                None => (path_name.to_string(), None),
+                None => (path_name.clone(), None),
             }
         };
         Ok(PackageIdSpec {

src/cargo/ops/cargo_compile.rs

@@ -169,7 +169,7 @@ pub fn compile_pkg<'a>(root_package: &Package,
         spec.iter().filter_map(|p| {
             match resolve_with_overrides.query(&p) {
                 Ok(p) => Some(p),
-                Err(..) => { invalid_spec.push(p.to_string()); None }
+                Err(..) => { invalid_spec.push(p.clone()); None }
             }
         }).collect::<Vec<_>>()
     } else {

src/cargo/ops/cargo_doc.rs

@@ -42,10 +42,10 @@ pub fn doc(manifest_path: &Path,
             bail!("Passing multiple packages and `open` is not supported")
         } else if options.compile_opts.spec.len() == 1 {
             try!(PackageIdSpec::parse(&options.compile_opts.spec[0]))
-                                             .name().replace("-", "_").to_string()
+                                             .name().replace("-", "_")
         } else {
             match lib_names.iter().chain(bin_names.iter()).nth(0) {
-                Some(s) => s.to_string(),
+                Some(s) => s.clone(),
                 None => return Ok(())
             }
         };

src/cargo/ops/cargo_install.rs

@@ -300,7 +300,7 @@ pub fn uninstall(root: Option<&str>,
 
         let bins = bins.iter().map(|s| {
             if s.ends_with(env::consts::EXE_SUFFIX) {
-                s.to_string()
+                s.clone()
             } else {
                 format!("{}{}", s, env::consts::EXE_SUFFIX)
             }

src/cargo/ops/cargo_new.rs

@@ -175,7 +175,6 @@ fn discover_author() -> CargoResult<(String, Option<String>)> {
     let git_config = GitConfig::open_default().ok();
     let git_config = git_config.as_ref();
     let name = git_config.and_then(|g| g.get_string("user.name").ok())
-                         .map(|s| s.to_string())
                          .or_else(|| env::var("USER").ok())      // unix
                          .or_else(|| env::var("USERNAME").ok()); // windows
     let name = match name {

src/cargo/ops/cargo_rustc/context.rs

@@ -134,7 +134,7 @@ impl<'a, 'cfg> Context<'a, 'cfg> {
             lines.next().unwrap().trim()
                  .split('_').skip(1).next().unwrap().to_string()
         };
-        Ok((dylib, exe_suffix.to_string()))
+        Ok((dylib, exe_suffix))
     }
 
     /// Prepare this context, ensuring that all filesystem directories are in
@@ -244,7 +244,7 @@ impl<'a, 'cfg> Context<'a, 'cfg> {
             None if unit.target.allows_underscores() => {
                 unit.target.name().to_string()
             }
-            None => unit.target.crate_name().to_string(),
+            None => unit.target.crate_name(),
         }
     }
 

src/cargo/ops/registry.rs

@@ -366,7 +366,7 @@ pub fn search(query: &str, config: &Config, index: Option<String>) -> CargoResul
             Some(desc) => {
                 let space = repeat(' ').take(description_margin - name.len())
                                        .collect::<String>();
-                name.to_string() + &space + &desc
+                name + &space + &desc
             }
             None => name
         };

src/cargo/sources/git/source.rs

@@ -43,7 +43,7 @@ impl<'cfg> GitSource<'cfg> {
         let reference_path = match *reference {
             GitReference::Branch(ref s) |
             GitReference::Tag(ref s) |
-            GitReference::Rev(ref s) => s.to_string(),
+            GitReference::Rev(ref s) => s.clone(),
         };
         let checkout_path = config.git_checkout_path()
                                   .join(&ident)