1 files changed, 52 insertions, 0 deletions
diff --git a/clap/src/completions/shell.rs b/clap/src/completions/shell.rs
new file mode 100644
index 0000000..19aab86
--- /dev/null
+++ b/clap/src/completions/shell.rs
@@ -0,0 +1,52 @@
+#[allow(deprecated, unused_imports)]
+use std::ascii::AsciiExt;
+use std::str::FromStr;
+use std::fmt;
+
+/// Describes which shell to produce a completions file for
+#[cfg_attr(feature = "lints", allow(enum_variant_names))]
+#[derive(Debug, Copy, Clone)]
+pub enum Shell {
+    /// Generates a .bash completion file for the Bourne Again SHell (BASH)
+    Bash,
+    /// Generates a .fish completion file for the Friendly Interactive SHell (fish)
+    Fish,
+    /// Generates a completion file for the Z SHell (ZSH)
+    Zsh,
+    /// Generates a completion file for PowerShell
+    PowerShell,
+    /// Generates a completion file for Elvish
+    Elvish,
+}
+
+impl Shell {
+    /// A list of possible variants in `&'static str` form
+    pub fn variants() -> [&'static str; 5] { ["zsh", "bash", "fish", "powershell", "elvish"] }
+}
+
+impl FromStr for Shell {
+    type Err = String;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        match s {
+            "ZSH" | _ if s.eq_ignore_ascii_case("zsh") => Ok(Shell::Zsh),
+            "FISH" | _ if s.eq_ignore_ascii_case("fish") => Ok(Shell::Fish),
+            "BASH" | _ if s.eq_ignore_ascii_case("bash") => Ok(Shell::Bash),
+            "POWERSHELL" | _ if s.eq_ignore_ascii_case("powershell") => Ok(Shell::PowerShell),
+            "ELVISH" | _ if s.eq_ignore_ascii_case("elvish") => Ok(Shell::Elvish),
+            _ => Err(String::from("[valid values: bash, fish, zsh, powershell, elvish]")),
+        }
+    }
+}
+
+impl fmt::Display for Shell {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        match *self {
+            Shell::Bash => write!(f, "BASH"),
+            Shell::Fish => write!(f, "FISH"),
+            Shell::Zsh => write!(f, "ZSH"),
+            Shell::PowerShell => write!(f, "POWERSHELL"),
+            Shell::Elvish => write!(f, "ELVISH"),
+        }
+    }
+}