Module devtools 

DevTools — Inspection, profiling, and debugging infrastructure.

Provides:

• Tree Inspector: snapshot the shadow tree into a serializable structure
• Layout Overlay: gather computed layout rectangles for overlay rendering
• Performance Profiler: track frame timing, layout stats, commit counts
• IR Replay: record and replay IR command batches
• WebSocket bridge types (protocol messages)

Structs

FrameRecord

A single frame timing record.

FrameTimer

Ongoing frame measurement.

IrRecorder

Records IR batches for later replay or debugging.

LayoutOverlay

All computed layout rectangles for overlay rendering.

LayoutRect

Computed layout rectangle for a node.

NodeSnapshot

Serializable snapshot of a single node (for DevTools UI).

OverlayRect

A single overlay rectangle with metadata.

ProfileSummary

Aggregated profiler statistics.

Profiler

Rolling profiler that keeps the last N frames of timing data.

TimestampedBatch

An IR batch with its relative timestamp.

Enums

DevToolsRequest

Messages from DevTools UI → Engine.

DevToolsResponse

Messages from Engine → DevTools UI.

Functions

gather_overlay

Gather all layout rectangles for the overlay. If highlight_id is set, that node is marked as highlighted.

handle_devtools_request

Handle an incoming DevTools request and produce a response.

snapshot_tree

Build a full tree snapshot starting from the root.