[Casing] Change default from verbatim to kebab.

.. fixes #202

CHANGELOG.md

@@ -9,6 +9,10 @@
   as `Option<Vec<T>>` is handled differently. If you need to have a `Option<Vec<T>>`
   handled the old was, you can `type Something = Vec<T>;` and then use `Option<Something>`
   as your structopt field.
+* Change default case from 'Verbatim' into 'Kebab' by [@0ndorio](https://github.com/0ndorio)
+  ([#202](https://github.com/TeXitoi/structopt/issues/202)). This is a breaking change.
+  If you rely on the old behavior you need to add `#[structopt(rename_all = "verbatim")]`
+  as an attribute to each data structure deriving the `StructOpt` trait.
 
 ## improvements
 

examples/rename_all.rs

@@ -1,7 +1,7 @@
 //! Example on how the `rename_all` parameter works.
 //!
 //! `rename_all` can be used to override the casing style used during argument
-//! generation. By default the `verbatim-case` style will be used but there are a wide
+//! generation. By default the `kebab-case` style will be used but there are a wide
 //! variety of other styles available.
 //!
 //! ## Supported styles overview:
@@ -59,13 +59,13 @@ enum Opt {
 
 #[derive(StructOpt, Debug)]
 enum Subcommands {
-    // This one will be available as `FirstSubcommand`.
+    // This one will be available as `first-subcommand`.
     FirstSubcommand,
 }
 
 #[derive(StructOpt, Debug)]
 struct BonusOptions {
-    // And this one will be available as `baz_option`.
+    // And this one will be available as `baz-option`.
     #[structopt(long)]
     baz_option: bool,
 }

src/lib.rs

@@ -186,6 +186,11 @@
 //! If an argument is renamed using `name = $NAME` any following call to
 //! `short` or `long` will use the new name.
 //!
+//! **Attention**: If these arguments are used without an explicit name
+//! the resulting flag is going to be renamed using `kebab-case` if the
+//! `rename_all` attribute was not specified previously. The same is true
+//! for subcommands with implicit naming through the related data structure.
+//!
 //! ```
 //! #[macro_use]
 //! extern crate structopt;

structopt-derive/src/lib.rs

@@ -26,7 +26,7 @@ use syn::token::Comma;
 use syn::*;
 
 /// Default casing style for generated arguments.
-const DEFAULT_CASING: CasingStyle = CasingStyle::Verbatim;
+const DEFAULT_CASING: CasingStyle = CasingStyle::Kebab;
 
 /// Output for the `gen_xxx()` methods were we need more than a simple stream of tokens.
 ///

tests/argument_naming.rs

@@ -4,15 +4,15 @@ extern crate structopt;
 use structopt::StructOpt;
 
 #[test]
-fn test_single_word_enum_variant_is_default_renamed_into_verbatim_case() {
+fn test_single_word_enum_variant_is_default_renamed_into_kebab_case() {
     #[derive(StructOpt, Debug, PartialEq)]
     enum Opt {
         Command { foo: u32 },
     }
 
     assert_eq!(
         Opt::Command { foo: 0 },
-        Opt::from_clap(&Opt::clap().get_matches_from(&["test", "Command", "0"]))
+        Opt::from_clap(&Opt::clap().get_matches_from(&["test", "command", "0"]))
     );
 }
 
@@ -25,12 +25,12 @@ fn test_multi_word_enum_variant_is_renamed() {
 
     assert_eq!(
         Opt::FirstCommand { foo: 0 },
-        Opt::from_clap(&Opt::clap().get_matches_from(&["test", "FirstCommand", "0"]))
+        Opt::from_clap(&Opt::clap().get_matches_from(&["test", "first-command", "0"]))
     );
 }
 
 #[test]
-fn test_standalone_long_generates_verbatim_case() {
+fn test_standalone_long_generates_kebab_case() {
     #[derive(StructOpt, Debug, PartialEq)]
     #[allow(non_snake_case)]
     struct Opt {
@@ -40,7 +40,7 @@ fn test_standalone_long_generates_verbatim_case() {
 
     assert_eq!(
         Opt { FOO_OPTION: true },
-        Opt::from_clap(&Opt::clap().get_matches_from(&["test", "--FOO_OPTION"]))
+        Opt::from_clap(&Opt::clap().get_matches_from(&["test", "--foo-option"]))
     );
 }
 
@@ -82,12 +82,12 @@ fn test_standalone_long_ignores_afterwards_defined_custom_name() {
 
     assert_eq!(
         Opt { foo_option: true },
-        Opt::from_clap(&Opt::clap().get_matches_from(&["test", "--foo_option"]))
+        Opt::from_clap(&Opt::clap().get_matches_from(&["test", "--foo-option"]))
     );
 }
 
 #[test]
-fn test_standalone_short_generates_verbatim_case() {
+fn test_standalone_short_generates_kebab_case() {
     #[derive(StructOpt, Debug, PartialEq)]
     #[allow(non_snake_case)]
     struct Opt {
@@ -97,7 +97,7 @@ fn test_standalone_short_generates_verbatim_case() {
 
     assert_eq!(
         Opt { FOO_OPTION: true },
-        Opt::from_clap(&Opt::clap().get_matches_from(&["test", "-F"]))
+        Opt::from_clap(&Opt::clap().get_matches_from(&["test", "-f"]))
     );
 }
 
@@ -259,7 +259,7 @@ fn test_rename_all_is_not_propagated_from_struct_into_subcommand() {
         Opt {
             foo: Foo::Command { foo: true }
         },
-        Opt::from_clap(&Opt::clap().get_matches_from(&["test", "Command", "--foo"]))
+        Opt::from_clap(&Opt::clap().get_matches_from(&["test", "command", "--foo"]))
     );
 }
 

tests/deny-warnings.rs

@@ -46,6 +46,6 @@ fn warning_never_enum() {
         Opt::Foo {
             s: "foo".to_string()
         },
-        Opt::from_iter(&["test", "Foo", "foo"])
+        Opt::from_iter(&["test", "foo", "foo"])
     );
 }

tests/subcommands.rs

@@ -217,7 +217,7 @@ fn flatten_enum() {
 
     assert!(Opt::from_iter_safe(&["test"]).is_err());
     assert_eq!(
-        Opt::from_iter(&["test", "Foo"]),
+        Opt::from_iter(&["test", "foo"]),
         Opt {
             sub_cmd: SubCmd::Foo
         }