refactor(cli): Align with clap 3.1 on terminology

clap 3.1 renamed `App` to `Command`.  When we upgrade to clap v4, the
lifetime will be removed and we can just use `clap::Command` instead of
a type alias.  This is prep for that.

Author: epage

src/bin/cargo/cli.rs

@@ -387,14 +387,14 @@ impl GlobalArgs {
     }
 }
 
-pub fn cli() -> App {
+pub fn cli() -> Command {
     let is_rustup = std::env::var_os("RUSTUP_HOME").is_some();
     let usage = if is_rustup {
         "cargo [+toolchain] [OPTIONS] [SUBCOMMAND]"
     } else {
         "cargo [OPTIONS] [SUBCOMMAND]"
     };
-    App::new("cargo")
+    Command::new("cargo")
         .allow_external_subcommands(true)
         .setting(AppSettings::DeriveDisplayOrder)
         // Doesn't mix well with our list of common cargo commands.  See clap-rs/clap#3108 for

src/bin/cargo/commands/add.rs

@@ -12,7 +12,7 @@ use cargo::util::interning::InternedString;
 use cargo::util::toml_mut::manifest::DepTable;
 use cargo::CargoResult;
 
-pub fn cli() -> clap::Command<'static> {
+pub fn cli() -> Command {
     clap::Command::new("add")
         .setting(clap::AppSettings::DeriveDisplayOrder)
         .about("Add dependencies to a Cargo.toml manifest file")

src/bin/cargo/commands/bench.rs

@@ -1,7 +1,7 @@
 use crate::command_prelude::*;
 use cargo::ops::{self, TestOptions};
 
-pub fn cli() -> App {
+pub fn cli() -> Command {
     subcommand("bench")
         .trailing_var_arg(true)
         .about("Execute all benchmarks of a local package")

src/bin/cargo/commands/build.rs

@@ -2,7 +2,7 @@ use crate::command_prelude::*;
 
 use cargo::ops;
 
-pub fn cli() -> App {
+pub fn cli() -> Command {
     subcommand("build")
         // subcommand aliases are handled in aliased_command()
         // .alias("b")

src/bin/cargo/commands/check.rs

@@ -2,7 +2,7 @@ use crate::command_prelude::*;
 
 use cargo::ops;
 
-pub fn cli() -> App {
+pub fn cli() -> Command {
     subcommand("check")
         // subcommand aliases are handled in aliased_command()
         // .alias("c")

src/bin/cargo/commands/clean.rs

@@ -3,7 +3,7 @@ use crate::command_prelude::*;
 use cargo::ops::{self, CleanOptions};
 use cargo::util::print_available_packages;
 
-pub fn cli() -> App {
+pub fn cli() -> Command {
     subcommand("clean")
         .about("Remove artifacts that cargo has generated in the past")
         .arg_quiet()

src/bin/cargo/commands/config.rs

@@ -1,7 +1,7 @@
 use crate::command_prelude::*;
 use cargo::ops::cargo_config;
 
-pub fn cli() -> App {
+pub fn cli() -> Command {
     subcommand("config")
         .about("Inspect configuration values")
         .after_help("Run `cargo help config` for more detailed information.\n")

src/bin/cargo/commands/doc.rs

@@ -2,7 +2,7 @@ use crate::command_prelude::*;
 
 use cargo::ops::{self, DocOptions};
 
-pub fn cli() -> App {
+pub fn cli() -> Command {
     subcommand("doc")
         // subcommand aliases are handled in aliased_command()
         // .alias("d")

src/bin/cargo/commands/fetch.rs

@@ -3,7 +3,7 @@ use crate::command_prelude::*;
 use cargo::ops;
 use cargo::ops::FetchOptions;
 
-pub fn cli() -> App {
+pub fn cli() -> Command {
     subcommand("fetch")
         .about("Fetch dependencies of a package from the network")
         .arg_quiet()

src/bin/cargo/commands/fix.rs

@@ -2,7 +2,7 @@ use crate::command_prelude::*;
 
 use cargo::ops;
 
-pub fn cli() -> App {
+pub fn cli() -> Command {
     subcommand("fix")
         .about("Automatically fix lint warnings reported by rustc")
         .arg_quiet()