From 07fbd4bd21667770364336cfef07c7f776ecf42e Mon Sep 17 00:00:00 2001
From: ysthakur <45539777+ysthakur@users.noreply.github.com>
Date: Wed, 3 Jan 2024 11:09:05 -0500
Subject: [PATCH 01/10] Don't slice line in DefaultCompleter

---
 examples/completions.rs   | 2 +-
 src/completion/default.rs | 2 +-
 src/menu/columnar_menu.rs | 7 +++++--
 src/menu/list_menu.rs     | 7 +++++--
 4 files changed, 12 insertions(+), 6 deletions(-)

diff --git a/examples/completions.rs b/examples/completions.rs
index 95f4975e..a7d8d3fb 100644
--- a/examples/completions.rs
+++ b/examples/completions.rs
@@ -29,7 +29,7 @@ fn main() -> io::Result<()> {
     ];
     let completer = Box::new(DefaultCompleter::new_with_wordlen(commands, 2));
     // Use the interactive menu to select options from the completer
-    let completion_menu = Box::new(ColumnarMenu::default().with_name("completion_menu"));
+    let completion_menu = Box::new(ColumnarMenu::default().with_name("completion_menu").with_only_buffer_difference(true));
 
     let mut keybindings = default_emacs_keybindings();
     add_menu_keybindings(&mut keybindings);
diff --git a/src/completion/default.rs b/src/completion/default.rs
index 11062d7b..73496b37 100644
--- a/src/completion/default.rs
+++ b/src/completion/default.rs
@@ -72,7 +72,7 @@ impl Completer for DefaultCompleter {
         let mut span_line_whitespaces = 0;
         let mut completions = vec![];
         if !line.is_empty() {
-            let mut split = line[0..pos].split(' ').rev();
+            let mut split = line.split(' ').rev();
             let mut span_line: String = String::new();
             for _ in 0..split.clone().count() {
                 if let Some(s) = split.next() {
diff --git a/src/menu/columnar_menu.rs b/src/menu/columnar_menu.rs
index ec391777..9e45adb7 100644
--- a/src/menu/columnar_menu.rs
+++ b/src/menu/columnar_menu.rs
@@ -530,7 +530,7 @@ impl Menu for ColumnarMenu {
             if let Some(old_string) = &self.input {
                 let (start, input) = string_difference(editor.get_buffer(), old_string);
                 if !input.is_empty() {
-                    self.values = completer.complete(input, start);
+                    self.values = completer.complete(input, start + input.len());
                     self.reset_position();
                 }
             }
@@ -541,7 +541,10 @@ impl Menu for ColumnarMenu {
             // Also, by replacing the new line character with a space, the insert
             // position is maintain in the line buffer.
             let trimmed_buffer = editor.get_buffer().replace('\n', " ");
-            self.values = completer.complete(trimmed_buffer.as_str(), editor.insertion_point());
+            self.values = completer.complete(
+                &trimmed_buffer[..editor.insertion_point()],
+                editor.insertion_point(),
+            );
             self.reset_position();
         }
     }
diff --git a/src/menu/list_menu.rs b/src/menu/list_menu.rs
index 5b10e68d..f92a14a7 100644
--- a/src/menu/list_menu.rs
+++ b/src/menu/list_menu.rs
@@ -402,13 +402,16 @@ impl Menu for ListMenu {
                     if input.is_empty() {
                         (line_buffer.insertion_point(), "")
                     } else {
-                        (start, input)
+                        (start + input.len(), input)
                     }
                 }
                 None => (line_buffer.insertion_point(), ""),
             }
         } else {
-            (line_buffer.insertion_point(), line_buffer.get_buffer())
+            (
+                line_buffer.insertion_point(),
+                &line_buffer.get_buffer()[..line_buffer.insertion_point()],
+            )
         };
 
         let parsed = parse_selection_char(input, SELECTION_CHAR);

From 950d66dbe6489b2d749e1525a7ba2e0d9921fb1d Mon Sep 17 00:00:00 2001
From: ysthakur <45539777+ysthakur@users.noreply.github.com>
Date: Wed, 3 Jan 2024 11:27:01 -0500
Subject: [PATCH 02/10] Revert completions example

---
 examples/completions.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/examples/completions.rs b/examples/completions.rs
index a7d8d3fb..95f4975e 100644
--- a/examples/completions.rs
+++ b/examples/completions.rs
@@ -29,7 +29,7 @@ fn main() -> io::Result<()> {
     ];
     let completer = Box::new(DefaultCompleter::new_with_wordlen(commands, 2));
     // Use the interactive menu to select options from the completer
-    let completion_menu = Box::new(ColumnarMenu::default().with_name("completion_menu").with_only_buffer_difference(true));
+    let completion_menu = Box::new(ColumnarMenu::default().with_name("completion_menu"));
 
     let mut keybindings = default_emacs_keybindings();
     add_menu_keybindings(&mut keybindings);

From 6a0fe0f4b25e2b7b56c96fe5990482cbb8a2dabe Mon Sep 17 00:00:00 2001
From: ysthakur <45539777+ysthakur@users.noreply.github.com>
Date: Wed, 3 Jan 2024 11:44:46 -0500
Subject: [PATCH 03/10] Fix clippy lint

---
 src/engine.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/engine.rs b/src/engine.rs
index 43555eec..30bb43bc 100644
--- a/src/engine.rs
+++ b/src/engine.rs
@@ -1538,7 +1538,7 @@ impl Reedline {
                         self.get_history_session_id(),
                     )))
                     .unwrap_or_else(|_| Vec::new())
-                    .get(0)
+                    .first()
                     .and_then(|history| history.command_line.split_whitespace().next_back())
                     .map(|token| (parsed.remainder.len(), indicator.len(), token.to_string())),
             });

From 8e3fb447a2d4299fd0a81155aec968333760ab36 Mon Sep 17 00:00:00 2001
From: ysthakur <45539777+ysthakur@users.noreply.github.com>
Date: Fri, 5 Jan 2024 12:02:07 -0500
Subject: [PATCH 04/10] Treat input as '' if None

---
 src/menu/columnar_menu.rs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/menu/columnar_menu.rs b/src/menu/columnar_menu.rs
index 9e45adb7..b0b571a6 100644
--- a/src/menu/columnar_menu.rs
+++ b/src/menu/columnar_menu.rs
@@ -533,6 +533,8 @@ impl Menu for ColumnarMenu {
                     self.values = completer.complete(input, start + input.len());
                     self.reset_position();
                 }
+            } else {
+                self.values = completer.complete("", editor.insertion_point());
             }
         } else {
             // If there is a new line character in the line buffer, the completer

From 65d0d5aab38b48c05904a4d29e52d03f0e93957c Mon Sep 17 00:00:00 2001
From: ysthakur <45539777+ysthakur@users.noreply.github.com>
Date: Fri, 5 Jan 2024 12:30:40 -0500
Subject: [PATCH 05/10] Update values even if string_difference empty

---
 src/menu/columnar_menu.rs | 20 +++++++++++---------
 1 file changed, 11 insertions(+), 9 deletions(-)

diff --git a/src/menu/columnar_menu.rs b/src/menu/columnar_menu.rs
index b0b571a6..7c466008 100644
--- a/src/menu/columnar_menu.rs
+++ b/src/menu/columnar_menu.rs
@@ -526,29 +526,31 @@ impl Menu for ColumnarMenu {
 
     /// Updates menu values
     fn update_values(&mut self, editor: &mut Editor, completer: &mut dyn Completer) {
-        if self.only_buffer_difference {
+        self.values = if self.only_buffer_difference {
             if let Some(old_string) = &self.input {
                 let (start, input) = string_difference(editor.get_buffer(), old_string);
                 if !input.is_empty() {
-                    self.values = completer.complete(input, start + input.len());
-                    self.reset_position();
+                    completer.complete(input, start + input.len())
+                } else {
+                    completer.complete("", editor.insertion_point())
                 }
             } else {
-                self.values = completer.complete("", editor.insertion_point());
+                completer.complete("", editor.insertion_point())
             }
         } else {
             // If there is a new line character in the line buffer, the completer
             // doesn't calculate the suggested values correctly. This happens when
             // editing a multiline buffer.
-            // Also, by replacing the new line character with a space, the insert
+            // Also, by replacing the new line character with a space, the insertF
             // position is maintain in the line buffer.
             let trimmed_buffer = editor.get_buffer().replace('\n', " ");
-            self.values = completer.complete(
+            completer.complete(
                 &trimmed_buffer[..editor.insertion_point()],
                 editor.insertion_point(),
-            );
-            self.reset_position();
-        }
+            )
+        };
+
+        self.reset_position();
     }
 
     /// The working details for the menu changes based on the size of the lines

From 297babba7f8bb7c9213cd46efba4cfa4c4134db5 Mon Sep 17 00:00:00 2001
From: ysthakur <45539777+ysthakur@users.noreply.github.com>
Date: Fri, 5 Jan 2024 14:20:04 -0500
Subject: [PATCH 06/10] Rename start to pos in list_menu

---
 src/menu/columnar_menu.rs | 2 +-
 src/menu/list_menu.rs     | 8 ++++----
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/src/menu/columnar_menu.rs b/src/menu/columnar_menu.rs
index 7c466008..980c706e 100644
--- a/src/menu/columnar_menu.rs
+++ b/src/menu/columnar_menu.rs
@@ -541,7 +541,7 @@ impl Menu for ColumnarMenu {
             // If there is a new line character in the line buffer, the completer
             // doesn't calculate the suggested values correctly. This happens when
             // editing a multiline buffer.
-            // Also, by replacing the new line character with a space, the insertF
+            // Also, by replacing the new line character with a space, the insert
             // position is maintain in the line buffer.
             let trimmed_buffer = editor.get_buffer().replace('\n', " ");
             completer.complete(
diff --git a/src/menu/list_menu.rs b/src/menu/list_menu.rs
index f92a14a7..d90e3672 100644
--- a/src/menu/list_menu.rs
+++ b/src/menu/list_menu.rs
@@ -395,7 +395,7 @@ impl Menu for ListMenu {
     /// Collecting the value from the completer to be shown in the menu
     fn update_values(&mut self, editor: &mut Editor, completer: &mut dyn Completer) {
         let line_buffer = editor.line_buffer();
-        let (start, input) = if self.only_buffer_difference {
+        let (pos, input) = if self.only_buffer_difference {
             match &self.input {
                 Some(old_string) => {
                     let (start, input) = string_difference(line_buffer.get_buffer(), old_string);
@@ -424,7 +424,7 @@ impl Menu for ListMenu {
         }
 
         self.values = if parsed.remainder.is_empty() {
-            self.query_size = Some(completer.total_completions(parsed.remainder, start));
+            self.query_size = Some(completer.total_completions(parsed.remainder, pos));
 
             let skip = self.pages.iter().take(self.page).sum::<Page>().size;
             let take = self
@@ -433,10 +433,10 @@ impl Menu for ListMenu {
                 .map(|page| page.size)
                 .unwrap_or(self.page_size);
 
-            completer.partial_complete(input, start, skip, take)
+            completer.partial_complete(input, pos, skip, take)
         } else {
             self.query_size = None;
-            completer.complete(input, start)
+            completer.complete(input, pos)
         }
     }
 

From 789c690e7dfec4d342d15ab8abbe7407bd7b0600 Mon Sep 17 00:00:00 2001
From: ysthakur <45539777+ysthakur@users.noreply.github.com>
Date: Fri, 5 Jan 2024 18:12:04 -0500
Subject: [PATCH 07/10] Fix string_diff bug with repeated char

---
 src/menu/menu_functions.rs | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/src/menu/menu_functions.rs b/src/menu/menu_functions.rs
index 8d15d696..f3400f4e 100644
--- a/src/menu/menu_functions.rs
+++ b/src/menu/menu_functions.rs
@@ -209,7 +209,7 @@ pub fn string_difference<'a>(new_string: &'a str, old_string: &str) -> (usize, &
                     false
                 }
             } else {
-                *c == old_chars[old_char_index].1
+                old_char_index == new_char_index && *c == old_chars[old_char_index].1
             };
 
             if equal {
@@ -479,6 +479,15 @@ mod tests {
         assert_eq!(res, (6, "ｓｈｅ"));
     }
 
+    #[test]
+    fn string_difference_with_repeat() {
+        let new_string = "ee";
+        let old_string = "e";
+
+        let res = string_difference(new_string, old_string);
+        assert_eq!(res, (1, "e"));
+    }
+
     #[test]
     fn find_common_string_with_ansi() {
         use crate::Span;

From 4342ff556454c856fcc7e6545c21293c971abe1e Mon Sep 17 00:00:00 2001
From: ysthakur <45539777+ysthakur@users.noreply.github.com>
Date: Fri, 5 Jan 2024 19:10:47 -0500
Subject: [PATCH 08/10] Trim before completing in DefaultCompleter

---
 src/completion/default.rs | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/completion/default.rs b/src/completion/default.rs
index 73496b37..171e30f3 100644
--- a/src/completion/default.rs
+++ b/src/completion/default.rs
@@ -71,6 +71,9 @@ impl Completer for DefaultCompleter {
     fn complete(&mut self, line: &str, pos: usize) -> Vec<Suggestion> {
         let mut span_line_whitespaces = 0;
         let mut completions = vec![];
+        // TODO trimming here is only necessary if someone passes in text containing
+        // stuff after the cursor with `only_buffer_difference: false`
+        let line = if line.len() > pos { &line[..pos] } else { line };
         if !line.is_empty() {
             let mut split = line.split(' ').rev();
             let mut span_line: String = String::new();

From f333f6c0a94377640f9f832e5135571823902587 Mon Sep 17 00:00:00 2001
From: ysthakur <45539777+ysthakur@users.noreply.github.com>
Date: Thu, 11 Jan 2024 10:24:34 -0500
Subject: [PATCH 09/10] Remove TODO

---
 src/completion/default.rs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/completion/default.rs b/src/completion/default.rs
index 171e30f3..4a3dd871 100644
--- a/src/completion/default.rs
+++ b/src/completion/default.rs
@@ -71,8 +71,8 @@ impl Completer for DefaultCompleter {
     fn complete(&mut self, line: &str, pos: usize) -> Vec<Suggestion> {
         let mut span_line_whitespaces = 0;
         let mut completions = vec![];
-        // TODO trimming here is only necessary if someone passes in text containing
-        // stuff after the cursor with `only_buffer_difference: false`
+        // Trimming in case someone passes in text containing stuff after the cursor, if
+        // `only_buffer_difference` is false
         let line = if line.len() > pos { &line[..pos] } else { line };
         if !line.is_empty() {
             let mut split = line.split(' ').rev();

From 8eefe0dbf76e41679ef887f53fd2b3eb1ebd1603 Mon Sep 17 00:00:00 2001
From: ysthakur <45539777+ysthakur@users.noreply.github.com>
Date: Thu, 11 Jan 2024 10:54:11 -0500
Subject: [PATCH 10/10] Make HistoryCompleter take end as pos

---
 src/completion/base.rs    | 3 ++-
 src/completion/history.rs | 4 ++--
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/src/completion/base.rs b/src/completion/base.rs
index 3de63c8d..fdf73696 100644
--- a/src/completion/base.rs
+++ b/src/completion/base.rs
@@ -24,7 +24,8 @@ impl Span {
     }
 }
 
-/// A trait that defines how to convert a line and position to a list of potential completions in that position.
+/// A trait that defines how to convert some text and a position to a list of potential completions in that position.
+/// The text could be a part of the whole line, and the position is the index of the end of the text in the original line.
 pub trait Completer: Send {
     /// the action that will take the line and position and convert it to a vector of completions, which include the
     /// span to replace and the contents of that replacement
diff --git a/src/completion/history.rs b/src/completion/history.rs
index ea6aedb6..324e3a17 100644
--- a/src/completion/history.rs
+++ b/src/completion/history.rs
@@ -52,8 +52,8 @@ impl<'menu> HistoryCompleter<'menu> {
 
     fn create_suggestion(&self, line: &str, pos: usize, value: &str) -> Suggestion {
         let span = Span {
-            start: pos,
-            end: pos + line.len(),
+            start: pos - line.len(),
+            end: pos,
         };
 
         Suggestion {