Implement EditorBuffer::move_cursor_to_line_number()

core/src/editor_buffer/mod.rs

@@ -27,8 +27,8 @@ pub enum CommandResponse {
 #[must_use]
 pub struct CommandResult {
     success: bool,
-    response: CommandResponse,
-    buffer: EditorBuffer,
+    pub response: CommandResponse,
+    pub buffer: EditorBuffer,
 }
 
 impl CommandResult {
@@ -93,14 +93,31 @@ impl EditorBuffer {
         })
     }
 
-    fn move_cursor_to_line_number(&self, _line_num: usize) -> CommandResult {
-        todo!()
+    fn move_cursor_to_line_number(&self, line_num: usize) -> CommandResult {
+        self.move_cursor_to_point(Point::LineColumn(line_num, 0))
     }
 
     fn insert_char(&self, c: char) -> CommandResult {
+        let newline = c == '\n';
         CommandResult::ok(Self {
             buffer: self.buffer.insert_char(c, self.cursor),
-            cursor: self.cursor.advance(),
+            cursor: match self.cursor {
+                Point::Start => {
+                    if newline {
+                        Point::LineColumn(1, 0)
+                    } else {
+                        Point::LineColumn(0, 1)
+                    }
+                }
+                Point::LineColumn(line, column) => {
+                    if newline {
+                        Point::LineColumn(line + 1, 0)
+                    } else {
+                        Point::LineColumn(line, column + 1)
+                    }
+                }
+                Point::End => Point::End,
+            },
             ..self.clone()
         })
     }
@@ -304,4 +321,57 @@ mod tests {
             .collect();
         assert_eq!(expected_lines, found_lines);
     }
+
+    #[test]
+    fn insert_line() {
+        let mut test_file = create_simple_test_file();
+        let mut file_contents = String::new();
+        test_file
+            .read_to_string(&mut file_contents)
+            .expect("Reading text file");
+        let test_file = test_file;
+        let mut expected_lines: Vec<_> = file_contents.lines().collect();
+        expected_lines.insert(6, "abc 123".into());
+
+        let target = EditorBuffer::new();
+        let result = target.execute(Command::OpenFile(test_file.path().into()));
+        assert!(result.is_ok());
+        let target = result.buffer;
+        let result = target.execute(Command::MoveCursorToLine(7));
+        assert!(result.is_ok());
+        let target = result.buffer;
+        let result = target.execute(Command::InsertChar('a'));
+        assert!(result.is_ok());
+        let target = result.buffer;
+        let result = target.execute(Command::InsertChar('b'));
+        assert!(result.is_ok());
+        let target = result.buffer;
+        let result = target.execute(Command::InsertChar('c'));
+        assert!(result.is_ok());
+        let target = result.buffer;
+        let result = target.execute(Command::InsertChar(' '));
+        assert!(result.is_ok());
+        let target = result.buffer;
+        let result = target.execute(Command::InsertChar('1'));
+        assert!(result.is_ok());
+        let target = result.buffer;
+        let result = target.execute(Command::InsertChar('2'));
+        assert!(result.is_ok());
+        let target = result.buffer;
+        let result = target.execute(Command::InsertChar('3'));
+        assert!(result.is_ok());
+        let target = result.buffer;
+        let result = target.execute(Command::InsertChar('\n'));
+        assert!(result.is_ok());
+        let target = result.buffer;
+        let found_lines: Vec<String> = target
+            .buffer
+            .iter_chars()
+            .collect::<String>()
+            .lines()
+            .map(|l| l.into())
+            .collect();
+        assert_eq!(expected_lines, found_lines);
+        assert_eq!(Point::LineColumn(8, 0), target.get_cursor_position());
+    }
 }

core/src/text_buffer/mod.rs

@@ -26,16 +26,6 @@ pub enum Point {
     End,
 }
 
-impl Point {
-    pub fn advance(self) -> Self {
-        match self {
-            Self::Start => Self::LineColumn(0, 1),
-            Self::LineColumn(l, c) => Self::LineColumn(l, c + 1),
-            Self::End => Self::End,
-        }
-    }
-}
-
 impl TextBuffer {
     /// Create a new empty [TextBuffer]
     pub fn new() -> Self {