Add support for Rust edition 2021.

Author: m-ou-se

src/cargo/core/features.rs

@@ -66,13 +66,16 @@ pub enum Edition {
     Edition2015,
     /// The 2018 edition
     Edition2018,
+    /// The 2021 edition
+    Edition2021,
 }
 
 impl fmt::Display for Edition {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         match *self {
             Edition::Edition2015 => f.write_str("2015"),
             Edition::Edition2018 => f.write_str("2018"),
+            Edition::Edition2021 => f.write_str("2021"),
         }
     }
 }
@@ -82,14 +85,15 @@ impl FromStr for Edition {
         match s {
             "2015" => Ok(Edition::Edition2015),
             "2018" => Ok(Edition::Edition2018),
-            s if s.parse().map_or(false, |y: u16| y > 2020 && y < 2050) => bail!(
+            "2021" => Ok(Edition::Edition2021),
+            s if s.parse().map_or(false, |y: u16| y > 2021 && y < 2050) => bail!(
                 "this version of Cargo is older than the `{}` edition, \
-                 and only supports `2015` and `2018` editions.",
+                 and only supports `2015`, `2018`, and `2021` editions.",
                 s
             ),
             s => bail!(
-                "supported edition values are `2015` or `2018`, but `{}` \
-                 is unknown",
+                "supported edition values are `2015`, `2018`, or `2021`, \
+                 but `{}` is unknown",
                 s
             ),
         }

src/cargo/util/command_prelude.rs

@@ -188,7 +188,7 @@ pub trait AppExt: Sized {
         ._arg(opt("lib", "Use a library template"))
         ._arg(
             opt("edition", "Edition to set for the crate generated")
-                .possible_values(&["2015", "2018"])
+                .possible_values(&["2015", "2018", "2021"])
                 .value_name("YEAR"),
         )
         ._arg(

src/doc/man/generated_txt/cargo-init.txt

@@ -69,7 +69,7 @@ OPTIONS
 
        --edition edition
            Specify the Rust edition to use. Default is 2018. Possible values:
-           2015, 2018
+           2015, 2018, 2021
 
        --name name
            Set the package name. Defaults to the directory name.

src/doc/man/generated_txt/cargo-new.txt

@@ -64,7 +64,7 @@ OPTIONS
 
        --edition edition
            Specify the Rust edition to use. Default is 2018. Possible values:
-           2015, 2018
+           2015, 2018, 2021
 
        --name name
            Set the package name. Defaults to the directory name.

src/doc/man/includes/options-new.md

@@ -11,7 +11,7 @@ Create a package with a library target (`src/lib.rs`).
 
 {{#option "`--edition` _edition_" }}
 Specify the Rust edition to use. Default is 2018.
-Possible values: 2015, 2018
+Possible values: 2015, 2018, 2021
 {{/option}}
 
 {{#option "`--name` _name_" }}

src/doc/src/commands/cargo-init.md

@@ -66,7 +66,7 @@ This is the default behavior.</dd>
 
 <dt class="option-term" id="option-cargo-init---edition"><a class="option-anchor" href="#option-cargo-init---edition"></a><code>--edition</code> <em>edition</em></dt>
 <dd class="option-desc">Specify the Rust edition to use. Default is 2018.
-Possible values: 2015, 2018</dd>
+Possible values: 2015, 2018, 2021</dd>
 
 
 <dt class="option-term" id="option-cargo-init---name"><a class="option-anchor" href="#option-cargo-init---name"></a><code>--name</code> <em>name</em></dt>

src/doc/src/commands/cargo-new.md

@@ -61,7 +61,7 @@ This is the default behavior.</dd>
 
 <dt class="option-term" id="option-cargo-new---edition"><a class="option-anchor" href="#option-cargo-new---edition"></a><code>--edition</code> <em>edition</em></dt>
 <dd class="option-desc">Specify the Rust edition to use. Default is 2018.
-Possible values: 2015, 2018</dd>
+Possible values: 2015, 2018, 2021</dd>
 
 
 <dt class="option-term" id="option-cargo-new---name"><a class="option-anchor" href="#option-cargo-new---name"></a><code>--name</code> <em>name</em></dt>

src/etc/_cargo

@@ -136,7 +136,7 @@ _cargo() {
                 init)
                     _arguments -s -S $common $registry \
                         '--lib[use library template]' \
-                        '--edition=[specify edition to set for the crate generated]:edition:(2015 2018)' \
+                        '--edition=[specify edition to set for the crate generated]:edition:(2015 2018 2021)' \
                         '--vcs=[initialize a new repo with a given VCS]:vcs:(git hg pijul fossil none)' \
                         '--name=[set the resulting package name]:name' \
                         '1:path:_directories'

src/etc/man/cargo-init.1

@@ -102,7 +102,7 @@ Create a package with a library target (\fBsrc/lib.rs\fR).
 \fB\-\-edition\fR \fIedition\fR
 .RS 4
 Specify the Rust edition to use. Default is 2018.
-Possible values: 2015, 2018
+Possible values: 2015, 2018, 2021
 .RE
 .sp
 \fB\-\-name\fR \fIname\fR

src/etc/man/cargo-new.1

@@ -97,7 +97,7 @@ Create a package with a library target (\fBsrc/lib.rs\fR).
 \fB\-\-edition\fR \fIedition\fR
 .RS 4
 Specify the Rust edition to use. Default is 2018.
-Possible values: 2015, 2018
+Possible values: 2015, 2018, 2021
 .RE
 .sp
 \fB\-\-name\fR \fIname\fR

tests/testsuite/package.rs

@@ -1043,7 +1043,7 @@ Caused by:
   failed to parse the `edition` key
 
 Caused by:
-  supported edition values are `2015` or `2018`, but `chicken` is unknown
+  supported edition values are `2015`, `2018`, or `2021`, but `chicken` is unknown
 "
             .to_string(),
         )
@@ -1075,7 +1075,7 @@ Caused by:
   failed to parse the `edition` key
 
 Caused by:
-  this version of Cargo is older than the `2038` edition, and only supports `2015` and `2018` editions.
+  this version of Cargo is older than the `2038` edition, and only supports `2015`, `2018`, and `2021` editions.
 "
             .to_string(),
         )