Make sort_completions helper

Used by command, custom, flag, and variable completions

crates/nu-cli/src/completions/command_completions.rs

@@ -9,7 +9,7 @@ use nu_protocol::{
 };
 use reedline::Suggestion;
 
-use super::SemanticSuggestion;
+use super::{completion_common::sort_completions, SemanticSuggestion};
 
 pub struct CommandCompletion {
     flattened: Vec<(Span, FlatShape)>,
@@ -161,7 +161,7 @@ impl Completer for CommandCompletion {
         &mut self,
         working_set: &StateWorkingSet,
         _stack: &Stack,
-        _prefix: Vec<u8>,
+        prefix: Vec<u8>,
         span: Span,
         offset: usize,
         pos: usize,
@@ -223,7 +223,12 @@ impl Completer for CommandCompletion {
             vec![]
         };
 
-        subcommands.into_iter().chain(commands).collect::<Vec<_>>()
+        let all_suggestions = subcommands.into_iter().chain(commands).collect::<Vec<_>>();
+        sort_completions(
+            &String::from_utf8_lossy(&prefix),
+            all_suggestions,
+            self.get_sort_by(),
+        )
     }
 
     fn get_sort_by(&self) -> SortBy {

crates/nu-cli/src/completions/completion_common.rs

@@ -1,16 +1,21 @@
-use crate::completions::{matches, CompletionOptions};
+use crate::{
+    completions::{matches, CompletionOptions},
+    SemanticSuggestion,
+};
 use nu_ansi_term::Style;
 use nu_engine::env_to_string;
 use nu_path::{expand_to_real_path, home_dir};
 use nu_protocol::{
     engine::{EngineState, Stack, StateWorkingSet},
-    Span,
+    levenshtein_distance, Span,
 };
 use nu_utils::get_ls_colors;
 use std::path::{
     is_separator, Component, Path, PathBuf, MAIN_SEPARATOR as SEP, MAIN_SEPARATOR_STR,
 };
 
+use super::SortBy;
+
 #[derive(Clone, Default)]
 pub struct PathBuiltFromString {
     parts: Vec<String>,
@@ -256,3 +261,28 @@ pub fn adjust_if_intermediate(
         readjusted,
     }
 }
+
+/// # Arguments
+/// * `prefix` - What the user's typed, for sorting by Levenshtein distance
+pub fn sort_completions(
+    prefix: &str,
+    mut items: Vec<SemanticSuggestion>,
+    sort_by: SortBy,
+) -> Vec<SemanticSuggestion> {
+    // Sort items
+    match sort_by {
+        SortBy::LevenshteinDistance => {
+            items.sort_by(|a, b| {
+                let a_distance = levenshtein_distance(prefix, &a.suggestion.value);
+                let b_distance = levenshtein_distance(prefix, &b.suggestion.value);
+                a_distance.cmp(&b_distance)
+            });
+        }
+        SortBy::Ascending => {
+            items.sort_by(|a, b| a.suggestion.value.cmp(&b.suggestion.value));
+        }
+        SortBy::None => {}
+    };
+
+    items
+}

crates/nu-cli/src/completions/custom_completions.rs

@@ -12,6 +12,8 @@ use nu_protocol::{
 use nu_utils::IgnoreCaseExt;
 use std::collections::HashMap;
 
+use super::completion_common::sort_completions;
+
 pub struct CustomCompletion {
     stack: Stack,
     decl_id: usize,
@@ -122,11 +124,16 @@ impl Completer for CustomCompletion {
             })
             .unwrap_or_default();
 
-        if let Some(custom_completion_options) = custom_completion_options {
+        let suggestions = if let Some(custom_completion_options) = custom_completion_options {
             filter(&prefix, suggestions, &custom_completion_options)
         } else {
             filter(&prefix, suggestions, completion_options)
-        }
+        };
+        sort_completions(
+            &String::from_utf8_lossy(&prefix),
+            suggestions,
+            self.get_sort_by(),
+        )
     }
 
     fn get_sort_by(&self) -> SortBy {

crates/nu-cli/src/completions/flag_completions.rs

@@ -1,4 +1,4 @@
-use crate::completions::{Completer, CompletionOptions};
+use crate::completions::{completion_common::sort_completions, Completer, CompletionOptions};
 use nu_protocol::{
     ast::{Expr, Expression},
     engine::{Stack, StateWorkingSet},
@@ -90,7 +90,11 @@ impl Completer for FlagCompletion {
                 }
             }
 
-            return output;
+            return sort_completions(
+                &String::from_utf8_lossy(&prefix),
+                output,
+                self.get_sort_by(),
+            );
         }
 
         vec![]

crates/nu-cli/src/completions/variable_completions.rs

@@ -9,6 +9,8 @@ use nu_protocol::{
 use reedline::Suggestion;
 use std::str;
 
+use super::completion_common::sort_completions;
+
 #[derive(Clone)]
 pub struct VariableCompletion {
     var_context: (Vec<u8>, Vec<Vec<u8>>), // tuple with $var and the sublevels (.b.c.d)
@@ -40,6 +42,7 @@ impl Completer for VariableCompletion {
             end: span.end - offset,
         };
         let sublevels_count = self.var_context.1.len();
+        let prefix_str = String::from_utf8_lossy(&prefix);
 
         // Completions for the given variable
         if !var_str.is_empty() {
@@ -69,7 +72,7 @@ impl Completer for VariableCompletion {
                             }
                         }
 
-                        return output;
+                        return sort_completions(&prefix_str, output, self.get_sort_by());
                     }
                 } else {
                     // No nesting provided, return all env vars
@@ -93,7 +96,7 @@ impl Completer for VariableCompletion {
                         }
                     }
 
-                    return output;
+                    return sort_completions(&prefix_str, output, self.get_sort_by());
                 }
             }
 
@@ -117,7 +120,7 @@ impl Completer for VariableCompletion {
                         }
                     }
 
-                    return output;
+                    return sort_completions(&prefix_str, output, self.get_sort_by());
                 }
             }
 
@@ -139,7 +142,7 @@ impl Completer for VariableCompletion {
                         }
                     }
 
-                    return output;
+                    return sort_completions(&prefix_str, output, self.get_sort_by());
                 }
             }
         }