feat: skip cursor movement to indentation

unhappychoice · claude · unhappychoice · commit 9ef01e202aac · 2025-11-25T15:43:29.000+09:00
When adding new lines, start typing at the indentation level instead of moving the cursor from column 0. This speeds up playback for deeply indented code and focuses on content changes rather than formatting. - Insert lines with indentation pre-filled - Position cursor at indentation end immediately - Type only the actual content characters 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com>
diff --git a/src/animation.rs b/src/animation.rs
@@ -668,17 +668,21 @@ impl AnimationEngine {
                     // (the next line moves up to this position)
                 }
                 LineChangeType::Addition => {
-                    // Insert empty line at current buffer position
+                    let content = &line_change.content;
+                    let indentation_len = content.chars().take_while(|c| c.is_whitespace()).count();
+
+                    // Insert line with indentation already included
+                    let indentation: String = content.chars().take(indentation_len).collect();
                     self.steps.push(AnimationStep::InsertLine {
                         line: buffer_line,
-                        content: String::new(),
+                        content: indentation,
                     });
 
-                    // Type each character
-                    for (col, ch) in line_change.content.chars().enumerate() {
+                    // Type each character after the indentation
+                    for (i, ch) in content.chars().skip(indentation_len).enumerate() {
                         self.steps.push(AnimationStep::InsertChar {
                             line: buffer_line,
-                            col,
+                            col: indentation_len + i,
                             ch,
                         });
                     }
@@ -822,9 +826,10 @@ impl AnimationEngine {
             }
             AnimationStep::InsertLine { line, content } => {
                 self.active_pane = ActivePane::Editor;
+                let content_len = content.chars().count();
                 self.buffer.insert_line(line, content);
                 self.buffer.cursor_line = line;
-                self.buffer.cursor_col = 0;
+                self.buffer.cursor_col = content_len;
 
                 // Track line offset for old_highlights mapping
                 self.line_offset += 1;
