Upgrade Cargo to the 2021 edition

This didn't actually result in any code changes yet, for now this simply
flips the edition flag for all of our crates and documentation.

Author: alexcrichton

Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 name = "cargo"
 version = "0.59.0"
-edition = "2018"
+edition = "2021"
 authors = ["Yehuda Katz <[email protected]>",
            "Carl Lerche <[email protected]>",
            "Alex Crichton <[email protected]>"]

benches/benchsuite/Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 name = "benchsuite"
 version = "0.1.0"
-edition = "2018"
+edition = "2021"
 license = "MIT OR Apache-2.0"
 homepage = "https://github.com/rust-lang/cargo"
 repository = "https://github.com/rust-lang/cargo"

benches/capture/Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 name = "capture"
 version = "0.1.0"
-edition = "2018"
+edition = "2021"
 license = "MIT OR Apache-2.0"
 description = "Tool for capturing a real-world workspace for benchmarking."
 

crates/cargo-platform/Cargo.toml

@@ -2,7 +2,7 @@
 name = "cargo-platform"
 version = "0.1.2"
 authors = ["The Cargo Project Developers"]
-edition = "2018"
+edition = "2021"
 license = "MIT OR Apache-2.0"
 homepage = "https://github.com/rust-lang/cargo"
 repository = "https://github.com/rust-lang/cargo"

crates/cargo-test-macro/Cargo.toml

@@ -2,7 +2,7 @@
 name = "cargo-test-macro"
 version = "0.1.0"
 authors = ["Jethro Beekman <[email protected]>"]
-edition = "2018"
+edition = "2021"
 license = "MIT OR Apache-2.0"
 homepage = "https://github.com/rust-lang/cargo"
 repository = "https://github.com/rust-lang/cargo"

crates/cargo-test-support/Cargo.toml

@@ -3,7 +3,7 @@ name = "cargo-test-support"
 version = "0.1.0"
 authors = ["Alex Crichton <[email protected]>"]
 license = "MIT OR Apache-2.0"
-edition = "2018"
+edition = "2021"
 
 [lib]
 doctest = false

crates/cargo-util/Cargo.toml

@@ -2,7 +2,7 @@
 name = "cargo-util"
 version = "0.1.1"
 authors = ["The Cargo Project Developers"]
-edition = "2018"
+edition = "2021"
 license = "MIT OR Apache-2.0"
 homepage = "https://github.com/rust-lang/cargo"
 repository = "https://github.com/rust-lang/cargo"

crates/crates-io/Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 name = "crates-io"
 version = "0.33.0"
-edition = "2018"
+edition = "2021"
 authors = ["Alex Crichton <[email protected]>"]
 license = "MIT OR Apache-2.0"
 repository = "https://github.com/rust-lang/cargo"

crates/credential/cargo-credential-1password/Cargo.toml

@@ -2,7 +2,7 @@
 name = "cargo-credential-1password"
 version = "0.1.0"
 authors = ["The Rust Project Developers"]
-edition = "2018"
+edition = "2021"
 license = "MIT OR Apache-2.0"
 repository = "https://github.com/rust-lang/cargo"
 description = "A Cargo credential process that stores tokens in a 1password vault."

crates/credential/cargo-credential-gnome-secret/Cargo.toml

@@ -2,7 +2,7 @@
 name = "cargo-credential-gnome-secret"
 version = "0.1.0"
 authors = ["The Rust Project Developers"]
-edition = "2018"
+edition = "2021"
 license = "MIT OR Apache-2.0"
 repository = "https://github.com/rust-lang/cargo"
 description = "A Cargo credential process that stores tokens with GNOME libsecret."

crates/credential/cargo-credential-macos-keychain/Cargo.toml

@@ -2,7 +2,7 @@
 name = "cargo-credential-macos-keychain"
 version = "0.1.0"
 authors = ["The Rust Project Developers"]
-edition = "2018"
+edition = "2021"
 license = "MIT OR Apache-2.0"
 repository = "https://github.com/rust-lang/cargo"
 description = "A Cargo credential process that stores tokens in a macOS keychain."

crates/credential/cargo-credential-wincred/Cargo.toml

@@ -2,7 +2,7 @@
 name = "cargo-credential-wincred"
 version = "0.1.0"
 authors = ["The Rust Project Developers"]
-edition = "2018"
+edition = "2021"
 license = "MIT OR Apache-2.0"
 repository = "https://github.com/rust-lang/cargo"
 description = "A Cargo credential process that stores tokens with Windows Credential Manager."

crates/credential/cargo-credential/Cargo.toml

@@ -2,7 +2,7 @@
 name = "cargo-credential"
 version = "0.1.0"
 authors = ["The Rust Project Developers"]
-edition = "2018"
+edition = "2021"
 license = "MIT OR Apache-2.0"
 repository = "https://github.com/rust-lang/cargo"
 description = "A library to assist writing Cargo credential helpers."

crates/mdman/Cargo.toml

@@ -2,7 +2,7 @@
 name = "mdman"
 version = "0.1.0"
 authors = ["Eric Huss"]
-edition = "2018"
+edition = "2021"
 license = "MIT OR Apache-2.0"
 description = "Creates a man page page from markdown."
 

src/doc/semver-check/Cargo.toml

@@ -2,7 +2,7 @@
 name = "semver-check"
 version = "0.1.0"
 authors = ["Eric Huss"]
-edition = "2018"
+edition = "2021"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 

src/doc/src/getting-started/first-steps.md

@@ -33,7 +33,7 @@ This is all we need to get started. First, let’s check out `Cargo.toml`:
 [package]
 name = "hello_world"
 version = "0.1.0"
-edition = "2018"
+edition = "2021"
 
 [dependencies]
 ```

src/doc/src/guide/creating-a-new-project.md

@@ -29,7 +29,7 @@ Let’s take a closer look at `Cargo.toml`:
 [package]
 name = "hello_world"
 version = "0.1.0"
-edition = "2018"
+edition = "2021"
 
 [dependencies]
 

src/doc/src/guide/dependencies.md

@@ -35,7 +35,7 @@ crates:
 [package]
 name = "hello_world"
 version = "0.1.0"
-edition = "2018"
+edition = "2021"
 
 [dependencies]
 time = "0.1.12"

src/doc/src/reference/build-script-examples.md

@@ -147,7 +147,7 @@ Pretty similar to before! Next, the manifest:
 [package]
 name = "hello-world-from-c"
 version = "0.1.0"
-edition = "2018"
+edition = "2021"
 ```
 
 For now we’re not going to use any build dependencies, so let’s take a look at
@@ -297,7 +297,7 @@ with `pkg-config` installed. Let's start by setting up the manifest:
 [package]
 name = "libz-sys"
 version = "0.1.0"
-edition = "2018"
+edition = "2021"
 links = "z"
 
 [build-dependencies]
@@ -384,7 +384,7 @@ Here's an example:
 [package]
 name = "zuser"
 version = "0.1.0"
-edition = "2018"
+edition = "2021"
 
 [dependencies]
 libz-sys = "1.0.25"