feat(completions): add auto_menu config for IDE-style completions

Adds `$env.config.completions.auto_menu` option (default: false) that
enables automatic completion menu display as you type.

When enabled:
- Completion menu appears after typing 1+ character for any argument
- Menu deactivates when typing just a space (waiting for next word)
- First word (commands) never auto-completes

Also switches hint provider from CwdAwareHinter to CompletionHinter
for fish-style inline suggestions based on completions rather than history.

Requires: nushell/reedline#993

Author: oxysoft

Cargo.lock

@@ -376,7 +376,8 @@ bench = false
 # To use a development version of a dependency please use a global override here
 # changing versions in each sub-crate of the workspace is tedious
 [patch.crates-io]
-reedline = { git = "https://github.com/nushell/reedline", branch = "main" }
+# Use fork with auto_complete_menu feature (PR: https://github.com/nushell/reedline/pull/993)
+reedline = { git = "https://github.com/oxysoft/reedline", branch = "feat/auto-complete-menu" }
 # nu-ansi-term = { git = "https://github.com/nushell/nu-ansi-term.git", branch = "main" }
 
 # Run all benchmarks with `cargo bench`

Cargo.toml

@@ -37,9 +37,10 @@ use nu_utils::{
 #[cfg(feature = "sqlite")]
 use reedline::SqliteBackedHistory;
 use reedline::{
-    CursorConfig, CwdAwareHinter, DefaultCompleter, EditCommand, Emacs, FileBackedHistory,
+    CompletionHinter, CursorConfig, DefaultCompleter, EditCommand, Emacs, FileBackedHistory,
     HistorySessionId, Reedline, Vi,
 };
+use std::sync::Mutex;
 use std::sync::atomic::Ordering;
 use std::{
     collections::HashMap,
@@ -400,6 +401,7 @@ fn loop_iteration(ctx: LoopContext) -> (bool, Stack, Reedline) {
         )))
         .with_quick_completions(config.completions.quick)
         .with_partial_completions(config.completions.partial)
+        .with_auto_complete_menu(config.completions.auto_menu)
         .with_ansi_colors(config.use_ansi_coloring.get(engine_state))
         .with_cwd(Some(
             engine_state
@@ -421,11 +423,15 @@ fn loop_iteration(ctx: LoopContext) -> (bool, Stack, Reedline) {
 
     start_time = std::time::Instant::now();
     line_editor = if config.use_ansi_coloring.get(engine_state) && config.show_hints {
-        line_editor.with_hinter(Box::new({
-            // As of Nov 2022, "hints" color_config closures only get `null` passed in.
-            let style = style_computer.compute("hints", &Value::nothing(Span::unknown()));
-            CwdAwareHinter::default().with_style(style)
-        }))
+        // Create a second completer for inline completion hints (fish-style autosuggestions)
+        let hint_completer = NuCompleter::new(
+            engine_reference.clone(),
+            stack_arc.clone(),
+        );
+        let style = style_computer.compute("hints", &Value::nothing(Span::unknown()));
+        line_editor.with_hinter(Box::new(
+            CompletionHinter::new(Arc::new(Mutex::new(hint_completer))).with_style(style)
+        ))
     } else {
         line_editor.disable_hints()
     };

crates/nu-cli/src/repl.rs

@@ -105,6 +105,7 @@ pub struct CompletionConfig {
     pub case_sensitive: bool,
     pub quick: bool,
     pub partial: bool,
+    pub auto_menu: bool,
     pub algorithm: CompletionAlgorithm,
     pub external: ExternalCompleterConfig,
     pub use_ls_colors: bool,
@@ -117,6 +118,7 @@ impl Default for CompletionConfig {
             case_sensitive: false,
             quick: true,
             partial: true,
+            auto_menu: false,
             algorithm: CompletionAlgorithm::default(),
             external: ExternalCompleterConfig::default(),
             use_ls_colors: true,
@@ -142,6 +144,7 @@ impl UpdateFromValue for CompletionConfig {
                 "sort" => self.sort.update(val, path, errors),
                 "quick" => self.quick.update(val, path, errors),
                 "partial" => self.partial.update(val, path, errors),
+                "auto_menu" => self.auto_menu.update(val, path, errors),
                 "algorithm" => self.algorithm.update(val, path, errors),
                 "case_sensitive" => self.case_sensitive.update(val, path, errors),
                 "external" => self.external.update(val, path, errors),