Merge #1975

1975: fix: Use character instead of string for Arg::Short r=CreepySkeleton a=lanesawyer



Co-authored-by: Lane Sawyer <github@lanesawyer.dev>

clap_derive/examples/basic.rs

@@ -30,7 +30,7 @@ struct Opt {
     // the long option will be translated by default to kebab case,
     // i.e. `--nb-cars`.
     /// Number of cars
-    #[clap(short = "c", long)]
+    #[clap(short = 'c', long)]
     nb_cars: Option<i32>,
 
     /// admin_level to consider

clap_derive/examples/keyvalue.rs

@@ -26,7 +26,7 @@ struct Opt {
     // but this makes adding an argument after the values impossible:
     // my_program -D a=1 -D b=2 my_input_file
     // becomes invalid.
-    #[clap(short = "D", parse(try_from_str = parse_key_val), number_of_values = 1)]
+    #[clap(short = 'D', parse(try_from_str = parse_key_val), number_of_values = 1)]
     defines: Vec<(String, i32)>,
 }
 

clap_derive/src/attrs.rs

@@ -147,11 +147,7 @@ impl ToTokens for Method {
     fn to_tokens(&self, ts: &mut proc_macro2::TokenStream) {
         let Method { ref name, ref args } = self;
 
-        let tokens = if name == "short" {
-            quote!( .#name(#args.chars().nth(0).unwrap()) )
-        } else {
-            quote!( .#name(#args) )
-        };
+        let tokens = quote!( .#name(#args) );
 
         tokens.to_tokens(ts);
     }
@@ -242,6 +238,28 @@ impl Name {
             }
         }
     }
+
+    pub fn translate_char(self, style: CasingStyle) -> TokenStream {
+        use CasingStyle::*;
+
+        match self {
+            Name::Assigned(tokens) => quote!( (#tokens).chars().next().unwrap() ),
+            Name::Derived(ident) => {
+                let s = ident.unraw().to_string();
+                let s = match style {
+                    Pascal => s.to_camel_case(),
+                    Kebab => s.to_kebab_case(),
+                    Camel => s.to_mixed_case(),
+                    ScreamingSnake => s.to_shouty_snake_case(),
+                    Snake => s.to_snake_case(),
+                    Verbatim => s,
+                };
+
+                let s = s.chars().next().unwrap();
+                quote_spanned!(ident.span()=> #s)
+            }
+        }
+    }
 }
 
 impl Attrs {
@@ -284,7 +302,11 @@ impl Attrs {
 
         for attr in parse_clap_attributes(attrs) {
             match attr {
-                Short(ident) | Long(ident) => {
+                Short(ident) => {
+                    self.push_method(ident, self.name.clone().translate_char(*self.casing));
+                }
+
+                Long(ident) => {
                     self.push_method(ident, self.name.clone().translate(*self.casing));
                 }
 

clap_derive/tests/argument_naming.rs

@@ -99,7 +99,7 @@ fn test_standalone_short_generates_kebab_case() {
 fn test_custom_short_overwrites_default_name() {
     #[derive(Clap, Debug, PartialEq)]
     struct Opt {
-        #[clap(short = "o")]
+        #[clap(short = 'o')]
         foo_option: bool,
     }
 

clap_derive/tests/basic.rs

@@ -18,7 +18,7 @@ use clap::Clap;
 fn basic() {
     #[derive(Clap, PartialEq, Debug)]
     struct Opt {
-        #[clap(short = "a", long = "arg")]
+        #[clap(short = 'a', long = "arg")]
         arg: Vec<i32>,
     }
     assert_eq!(Opt { arg: vec![24] }, Opt::parse_from(&["test", "-a24"]));

clap_derive/tests/custom-string-parsers.rs

@@ -32,7 +32,7 @@ struct PathOpt {
     #[clap(short, parse(from_os_str))]
     option_path_1: Option<PathBuf>,
 
-    #[clap(short = "q", parse(from_os_str))]
+    #[clap(short = 'q', parse(from_os_str))]
     option_path_2: Option<PathBuf>,
 }
 
@@ -179,7 +179,7 @@ struct Occurrences {
     #[clap(short, parse(from_occurrences))]
     unsigned: usize,
 
-    #[clap(short = "r", parse(from_occurrences))]
+    #[clap(short = 'r', parse(from_occurrences))]
     little_unsigned: u8,
 
     #[clap(short, long, parse(from_occurrences = foo))]

clap_derive/tests/explicit_name_no_renaming.rs

@@ -7,7 +7,7 @@ use utils::*;
 fn explicit_short_long_no_rename() {
     #[derive(Clap, PartialEq, Debug)]
     struct Opt {
-        #[clap(short = ".", long = ".foo")]
+        #[clap(short = '.', long = ".foo")]
         foo: Vec<String>,
     }
 

clap_derive/tests/non_literal_attributes.rs

@@ -30,7 +30,7 @@ struct Opt {
     )]
     x: i32,
 
-    #[clap(short = "l", long = "level", aliases = &["set-level", "lvl"])]
+    #[clap(short = 'l', long = "level", aliases = &["set-level", "lvl"])]
     level: String,
 
     #[clap(long("values"))]
@@ -129,7 +129,7 @@ fn parse_hex(input: &str) -> Result<u64, ParseIntError> {
 
 #[derive(Clap, PartialEq, Debug)]
 struct HexOpt {
-    #[clap(short = "n", parse(try_from_str = parse_hex))]
+    #[clap(short, parse(try_from_str = parse_hex))]
     number: u64,
 }