1 files changed, 121 insertions, 0 deletions
diff --git a/src/dynamic/shells/bash.rs b/src/dynamic/shells/bash.rs
new file mode 100644
index 0000000..43c128e
--- /dev/null
+++ b/src/dynamic/shells/bash.rs
@@ -0,0 +1,121 @@
+use unicode_xid::UnicodeXID as _;
+
+/// Bash completions
+#[derive(Copy, Clone, PartialEq, Eq, Debug)]
+pub struct Bash;
+
+impl crate::dynamic::Completer for Bash {
+    fn file_name(&self, name: &str) -> String {
+        format!("{name}.bash")
+    }
+    fn write_registration(
+        &self,
+        name: &str,
+        bin: &str,
+        completer: &str,
+        buf: &mut dyn std::io::Write,
+    ) -> Result<(), std::io::Error> {
+        let escaped_name = name.replace('-', "_");
+        debug_assert!(
+            escaped_name.chars().all(|c| c.is_xid_continue()),
+            "`name` must be an identifier, got `{escaped_name}`"
+        );
+        let mut upper_name = escaped_name.clone();
+        upper_name.make_ascii_uppercase();
+
+        let completer = shlex::quote(completer);
+
+        let script = r#"
+_clap_complete_NAME() {
+    export IFS=$'\013'
+    export _CLAP_COMPLETE_INDEX=${COMP_CWORD}
+    export _CLAP_COMPLETE_COMP_TYPE=${COMP_TYPE}
+    if compopt +o nospace 2> /dev/null; then
+        export _CLAP_COMPLETE_SPACE=false
+    else
+        export _CLAP_COMPLETE_SPACE=true
+    fi
+    COMPREPLY=( $("COMPLETER" complete --shell bash -- "${COMP_WORDS[@]}") )
+    if [[ $? != 0 ]]; then
+        unset COMPREPLY
+    elif [[ $SUPPRESS_SPACE == 1 ]] && [[ "${COMPREPLY-}" =~ [=/:]$ ]]; then
+        compopt -o nospace
+    fi
+}
+complete -o nospace -o bashdefault -F _clap_complete_NAME BIN
+"#
+        .replace("NAME", &escaped_name)
+        .replace("BIN", bin)
+        .replace("COMPLETER", &completer)
+        .replace("UPPER", &upper_name);
+
+        writeln!(buf, "{script}")?;
+        Ok(())
+    }
+    fn write_complete(
+        &self,
+        cmd: &mut clap::Command,
+        args: Vec<std::ffi::OsString>,
+        current_dir: Option<&std::path::Path>,
+        buf: &mut dyn std::io::Write,
+    ) -> Result<(), std::io::Error> {
+        let index: usize = std::env::var("_CLAP_COMPLETE_INDEX")
+            .ok()
+            .and_then(|i| i.parse().ok())
+            .unwrap_or_default();
+        let _comp_type: CompType = std::env::var("_CLAP_COMPLETE_COMP_TYPE")
+            .ok()
+            .and_then(|i| i.parse().ok())
+            .unwrap_or_default();
+        let _space: Option<bool> = std::env::var("_CLAP_COMPLETE_SPACE")
+            .ok()
+            .and_then(|i| i.parse().ok());
+        let ifs: Option<String> = std::env::var("IFS").ok().and_then(|i| i.parse().ok());
+        let completions = crate::dynamic::complete(cmd, args, index, current_dir)?;
+
+        for (i, (completion, _)) in completions.iter().enumerate() {
+            if i != 0 {
+                write!(buf, "{}", ifs.as_deref().unwrap_or("\n"))?;
+            }
+            write!(buf, "{}", completion.to_string_lossy())?;
+        }
+        Ok(())
+    }
+}
+
+/// Type of completion attempted that caused a completion function to be called
+#[derive(Copy, Clone, Debug, PartialEq, Eq)]
+#[non_exhaustive]
+enum CompType {
+    /// Normal completion
+    Normal,
+    /// List completions after successive tabs
+    Successive,
+    /// List alternatives on partial word completion
+    Alternatives,
+    /// List completions if the word is not unmodified
+    Unmodified,
+    /// Menu completion
+    Menu,
+}
+
+impl std::str::FromStr for CompType {
+    type Err = String;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        match s {
+            "9" => Ok(Self::Normal),
+            "63" => Ok(Self::Successive),
+            "33" => Ok(Self::Alternatives),
+            "64" => Ok(Self::Unmodified),
+            "37" => Ok(Self::Menu),
+            _ => Err(format!("unsupported COMP_TYPE `{}`", s)),
+        }
+    }
+}
+
+impl Default for CompType {
+    fn default() -> Self {
+        Self::Normal
+    }
+}