fix(derive): Remove deprecated arg_enum attribute

CHANGELOG.md

@@ -52,6 +52,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 - *(env)* Parse `--help` and `--version` like any `ArgAction::SetTrue` flag (#3776)
 - *(derive)* Changed the default for arguments from `parse` to `value_parser`., removing `parse` support
 - *(derive)* `subcommand_required(true).arg_required_else_help(true)` is set instead of `SubcommandRequiredElseHelp` (#3280)
+- *(derive)* Remove `arg_enum` attribute in favor of `value_enum`
 
 ### Compatibility
 

clap_complete/examples/completion-derive.rs

@@ -26,7 +26,7 @@ use std::path::PathBuf;
 )]
 struct Opt {
     /// If provided, outputs the completion file for given shell
-    #[clap(long = "generate", arg_enum)]
+    #[clap(long = "generate", value_enum)]
     generator: Option<Shell>,
     // Showcasing all possible ValueHints:
     #[clap(long, value_hint = ValueHint::Unknown)]

clap_derive/src/parse.rs

@@ -155,7 +155,6 @@ impl Parse for ClapAttr {
                 "action" => Ok(Action(name)),
                 "env" => Ok(Env(name)),
                 "flatten" => Ok(Flatten(name)),
-                "arg_enum" => Ok(ValueEnum(name)),
                 "value_enum" => Ok(ValueEnum(name)),
                 "from_global" => Ok(FromGlobal(name)),
                 "subcommand" => Ok(Subcommand(name)),

examples/tutorial_derive/04_01_enum.rs

@@ -4,7 +4,7 @@ use clap::{Parser, ValueEnum};
 #[clap(author, version, about, long_about = None)]
 struct Cli {
     /// What mode to run the program in
-    #[clap(arg_enum)]
+    #[clap(value_enum)]
     mode: Mode,
 }