Log error instead of panics in `InlineAssistant::scroll_to_assist` (#32519)

Michael Sloan created 6 months ago

Leaving release notes blank as it's not very actionable to know that a
rare crash might be fixed.

Release Notes:

- N/A

Change summary

crates/agent/src/inline_assistant.rs | 35 ++++++++++++++++-------------
1 file changed, 19 insertions(+), 16 deletions(-)

Detailed changes

crates/agent/src/inline_assistant.rs

@@ -38,8 +38,7 @@ use telemetry_events::{AssistantEventData, AssistantKind, AssistantPhase};
 use terminal_view::{TerminalView, terminal_panel::TerminalPanel};
 use text::{OffsetRangeExt, ToPoint as _};
 use ui::prelude::*;
-use util::RangeExt;
-use util::ResultExt;
+use util::{RangeExt, ResultExt, maybe};
 use workspace::{ItemHandle, Toast, Workspace, dock::Panel, notifications::NotificationId};
 use zed_actions::agent::OpenConfiguration;
 
@@ -1171,27 +1170,31 @@ impl InlineAssistant {
                 selections.select_anchor_ranges([position..position])
             });
 
-            let mut scroll_target_top;
-            let mut scroll_target_bottom;
+            let mut scroll_target_range = None;
             if let Some(decorations) = assist.decorations.as_ref() {
-                scroll_target_top = editor
-                    .row_for_block(decorations.prompt_block_id, cx)
-                    .unwrap()
-                    .0 as f32;
-                scroll_target_bottom = editor
-                    .row_for_block(decorations.end_block_id, cx)
-                    .unwrap()
-                    .0 as f32;
-            } else {
+                scroll_target_range = maybe!({
+                    let top = editor.row_for_block(decorations.prompt_block_id, cx)?.0 as f32;
+                    let bottom = editor.row_for_block(decorations.end_block_id, cx)?.0 as f32;
+                    Some((top, bottom))
+                });
+                if scroll_target_range.is_none() {
+                    log::error!("bug: failed to find blocks for scrolling to inline assist");
+                }
+            }
+            let scroll_target_range = scroll_target_range.unwrap_or_else(|| {
                 let snapshot = editor.snapshot(window, cx);
                 let start_row = assist
                     .range
                     .start
                     .to_display_point(&snapshot.display_snapshot)
                     .row();
-                scroll_target_top = start_row.0 as f32;
-                scroll_target_bottom = scroll_target_top + 1.;
-            }
+                let top = start_row.0 as f32;
+                let bottom = top + 1.0;
+                (top, bottom)
+            });
+            let mut scroll_target_top = scroll_target_range.0;
+            let mut scroll_target_bottom = scroll_target_range.1;
+
             scroll_target_top -= editor.vertical_scroll_margin() as f32;
             scroll_target_bottom += editor.vertical_scroll_margin() as f32;