feat(macros): relax completion attribute signature

Allow completion functions to omit the context parameter, accept owned
ShellContext or any From<&ShellContext> type, and return any type
implementing Into<Suggest>. Add From<&str> for SuggestItem and derive
Clone for ShellContext.

1 files changed, 7 insertions, 1 deletions

diff --git a/mingling_core/src/comp/shell_ctx.rs b/mingling_core/src/comp/shell_ctx.rs
index 552e514..3a1b8f2 100644
--- a/mingling_core/src/comp/shell_ctx.rs
+++ b/mingling_core/src/comp/shell_ctx.rs
@@ -96,7 +96,7 @@ use std::collections::HashSet;
 /// If the `-F` flag is present without a value, `shell_flag` becomes
 /// `ShellFlag::Other(String::new())`. If `-F` is absent, it defaults to
 /// `ShellFlag::Other("unknown".to_string())`.
-#[derive(Default, Debug)]
+#[derive(Default, Debug, Clone)]
 #[cfg_attr(feature = "structural_renderer", derive(serde::Serialize))]
 pub struct ShellContext {
     /// The full command line
@@ -182,6 +182,12 @@ impl TryFrom<Vec<String>> for ShellContext {
     }
 }
 
+impl From<&Self> for ShellContext {
+    fn from(ctx: &Self) -> Self {
+        ctx.clone()
+    }
+}
+
 impl ShellContext {
     /// Checks if a flag appears exactly once in the command line arguments.
     ///