Auto merge of #6347 - Eh2406:dell-copy, r=alexcrichton

remove clones made redundant by Intern SourceId

This is a follow up to #6342. I used clippy to find all the places we called `.clone()`  on a `SourceId` or where we passed `&SourceId`. This also involved fixing a large number of other things clippy was complaining about, and running `fmt` on a large number of files.

src/bin/cargo/cli.rs

@@ -81,7 +81,7 @@ Run with 'cargo -Z [FLAG] [SUBCOMMAND]'"
 
 pub fn get_version_string(is_verbose: bool) -> String {
     let version = cargo::version();
-    let mut version_string = String::from(version.to_string());
+    let mut version_string = version.to_string();
     version_string.push_str("\n");
     if is_verbose {
         version_string.push_str(&format!(
@@ -218,9 +218,10 @@ See 'cargo help <command>' for more information on a specific command.\n",
             opt(
                 "verbose",
                 "Use verbose output (-vv very verbose/build.rs output)",
-            ).short("v")
-                .multiple(true)
-                .global(true),
+            )
+            .short("v")
+            .multiple(true)
+            .global(true),
         )
         .arg(
             opt("quiet", "No output printed to stdout")

src/bin/cargo/commands/git_checkout.rs

@@ -28,7 +28,7 @@ pub fn exec(config: &mut Config, args: &ArgMatches) -> CliResult {
     let reference = GitReference::Branch(reference.to_string());
     let source_id = SourceId::for_git(&url, reference)?;
 
-    let mut source = GitSource::new(&source_id, config)?;
+    let mut source = GitSource::new(source_id, config)?;
 
     source.update()?;
 

src/bin/cargo/commands/install.rs

@@ -82,7 +82,8 @@ pub fn exec(config: &mut Config, args: &ArgMatches) -> CliResult {
 
     compile_opts.build_config.release = !args.is_present("debug");
 
-    let krates = args.values_of("crate")
+    let krates = args
+        .values_of("crate")
         .unwrap_or_default()
         .collect::<Vec<_>>();
 
@@ -120,7 +121,7 @@ pub fn exec(config: &mut Config, args: &ArgMatches) -> CliResult {
         ops::install(
             root,
             krates,
-            &source,
+            source,
             from_cwd,
             version,
             &compile_opts,

src/bin/cargo/commands/login.rs

@@ -3,9 +3,9 @@ use command_prelude::*;
 use std::io::{self, BufRead};
 
 use cargo::core::{Source, SourceId};
+use cargo::ops;
 use cargo::sources::RegistrySource;
 use cargo::util::{CargoError, CargoResultExt};
-use cargo::ops;
 
 pub fn cli() -> App {
     subcommand("login")
@@ -29,11 +29,12 @@ pub fn exec(config: &mut Config, args: &ArgMatches) -> CliResult {
                     return Err(format_err!(
                         "token must be provided when \
                          --registry is provided."
-                    ).into());
+                    )
+                    .into());
                 }
                 None => {
                     let src = SourceId::crates_io(config)?;
-                    let mut src = RegistrySource::remote(&src, config);
+                    let mut src = RegistrySource::remote(src, config);
                     src.update()?;
                     let config = src.config()?.unwrap();
                     args.value_of("host")

src/bin/cargo/main.rs

@@ -1,5 +1,5 @@
-#![cfg_attr(feature = "cargo-clippy", allow(too_many_arguments))] // large project
-#![cfg_attr(feature = "cargo-clippy", allow(redundant_closure))]  // there's a false positive
+#![cfg_attr(feature = "cargo-clippy", allow(clippy::too_many_arguments))] // large project
+#![cfg_attr(feature = "cargo-clippy", allow(clippy::redundant_closure))]  // there's a false positive
 
 extern crate cargo;
 extern crate clap;
@@ -13,10 +13,10 @@ extern crate serde_derive;
 extern crate serde_json;
 extern crate toml;
 
+use std::collections::BTreeSet;
 use std::env;
 use std::fs;
 use std::path::{Path, PathBuf};
-use std::collections::BTreeSet;
 
 use cargo::core::shell::Shell;
 use cargo::util::{self, command_prelude, lev_distance, CargoResult, CliResult, Config};

src/cargo/core/compiler/build_context/mod.rs

@@ -88,7 +88,8 @@ impl<'a, 'cfg> BuildContext<'a, 'cfg> {
     }
 
     pub fn extern_crate_name(&self, unit: &Unit<'a>, dep: &Unit<'a>) -> CargoResult<String> {
-        self.resolve.extern_crate_name(unit.pkg.package_id(), dep.pkg.package_id(), dep.target)
+        self.resolve
+            .extern_crate_name(unit.pkg.package_id(), dep.pkg.package_id(), dep.target)
     }
 
     /// Whether a dependency should be compiled for the host or target platform,
@@ -266,10 +267,12 @@ impl TargetConfig {
                         let list = value.list(k)?;
                         output.cfgs.extend(list.iter().map(|v| v.0.clone()));
                     }
-                    "rustc-env" => for (name, val) in value.table(k)?.0 {
-                        let val = val.string(name)?.0;
-                        output.env.push((name.clone(), val.to_string()));
-                    },
+                    "rustc-env" => {
+                        for (name, val) in value.table(k)?.0 {
+                            let val = val.string(name)?.0;
+                            output.env.push((name.clone(), val.to_string()));
+                        }
+                    }
                     "warning" | "rerun-if-changed" | "rerun-if-env-changed" => {
                         bail!("`{}` is not supported in build script overrides", k);
                     }
@@ -342,7 +345,8 @@ fn env_args(
 
     // First try RUSTFLAGS from the environment
     if let Ok(a) = env::var(name) {
-        let args = a.split(' ')
+        let args = a
+            .split(' ')
             .map(str::trim)
             .filter(|s| !s.is_empty())
             .map(str::to_string);
@@ -351,7 +355,8 @@ fn env_args(
 
     let mut rustflags = Vec::new();
 
-    let name = name.chars()
+    let name = name
+        .chars()
         .flat_map(|c| c.to_lowercase())
         .collect::<String>();
     // Then the target.*.rustflags value...
@@ -367,13 +372,10 @@ fn env_args(
     // ...including target.'cfg(...)'.rustflags
     if let Some(target_cfg) = target_cfg {
         if let Some(table) = config.get_table("target")? {
-            let cfgs = table.val.keys().filter_map(|key| {
-                if CfgExpr::matches_key(key, target_cfg) {
-                    Some(key)
-                } else {
-                    None
-                }
-            });
+            let cfgs = table
+                .val
+                .keys()
+                .filter(|key| CfgExpr::matches_key(key, target_cfg));
 
             // Note that we may have multiple matching `[target]` sections and
             // because we're passing flags to the compiler this can affect