Drag to Select and Copy in the Monitor
Grab text out of any pane or error popup with the mouse, and copy it on release
0 milestones 5 sprints
1h 20m total 14m 46s per sprint
30.6M tokens in 215.2k tokens out
$30.67 nominal cost
Gantry's build monitor is a terminal interface with activity cards, a sprint sidebar, a chat transcript, and popups for errors, prompts, sessions, stats, and help. This job gave that monitor its own text selection model after terminal mouse capture had made native drag selection unsuitable for the app's divider and menu behavior.
The run treated selection as a set of testable seams: terminal mouse mode and state, per-frame text registration, modal scoping, gesture routing, clipboard copy, and a final highlight pass. Standing in the current tree, those pieces remain in the TUI code, though the selection crate dependency has since been vendored with the other mcurses crates.
How this walkthrough is structured
Feature
What did the run build and ship?
The monitor now owns selectable text blocks, routes drag gestures through them, copies selected text on release, and paints the selected cells after the frame renders.
Build
How did Gantry structure the work?
The cut turned a mouse feature the gate could not drive directly into independently provable state, registration, routing, and paint steps.
Milestone 1
Restore menu hover + divider, and add app-level text selection on every pane
At the current tree, the milestone's shape is still recognizable across the TUI modules. State owns a block registry and selection manager, rendering rebuilds selectable blocks each frame and applies a highlight at the end, and mouse handling routes press, drag, and release through the selection manager while preserving divider and menu behavior. Later work expanded the overlay set, but the app-level selection model remains the one this job installed.
The milestone brief carried the whole feature as one coherent slab, but its boundaries were written around what automated tests could prove without a real pointer. It separated terminal setup, frame-local registration, gesture interpretation, and visual feedback, so each fresh agent got one layer of the interaction rather than the whole terminal behavior at once. The run record shows no retry or re-plan, and the only extra gate activity came after the final paint step, where the complete stack was checked again.
Selection Foundation
The foundation still stands, with the dependency now vendored rather than reached through a sibling checkout. The terminal enables any-event mouse tracking with symmetric teardown, and the comment explains the trade between native terminal selection and app-level selection. App state still carries the selection manager and per-frame block registry beside the divider column, and draw still clears that registry before panes register text.
This sprint was asked to lay the dependency, terminal mode, and state foundation before any text region was selectable. That was a memoryless-sized slice because it touched clear setup points: the cargo dependency, mouse enable and disable constants, and the app state fields cleared during draw. Its boundary stayed green, which meant later agents could rely on a built selection manager and a registry that began each frame empty.
Pane Block Registration
The pane registry remains visible in the renderer and state helpers. Feed cards use stable ids derived from their append-only card position, while the sidebar and chat transcript use singleton ids. The registered regions are the inner text actually drawn, leaving gutters, pads, borders, and other chrome unregistered and therefore unselectable.
This sprint carried only the observation half of selection for the always-visible panes. The brief kept it free of gesture logic, so the agent could focus on stable block identifiers, live rectangles, rendered lines, and tests over a deterministic frame. Its green boundary showed that feed cards, the sidebar, and chat could be proven as data before any mouse event consumed them.
Overlay Registration
Overlay selection is still keyed through the shared overlay block-id space. The current tree names the frontmost overlay explicitly and registers only that overlay's text while it owns input, suppressing pane blocks beneath it. The list has grown to include newer modal surfaces, which is evidence that the original singleton-id convention remained usable after the job.
The overlay sprint extended the same registration contract to the modal surfaces and added the ownership rule that panes underneath an open overlay are not hit-testable. That made it a contained task: reuse the block-id convention, inspect each overlay draw path, and assert that only the frontmost text body registers. The run stayed green here, so modal scoping was settled before gesture routing leaned on it.
Gesture & Copy Routing
Mouse routing still contains the selection precedence this sprint introduced. A divider press arms resizing instead of selection, ordinary left presses can anchor in a registered block, drags extend within that block, and release finalizes the gesture. Copy still goes through the selection manager's clipboard path, while no-drag clicks clear a stale selection and keep their existing app action.
This sprint was the behavioral center of the job, and it arrived only after blocks existed to hit-test. The brief first extracted mouse routing into a function tests could call with synthetic events, then layered selection around divider, chat, wheel, and menu handling. Its boundary stayed green, indicating the difficult interaction rule was carried by tests over explicit press, drag, release, clamp, and extraction cases rather than by manual clicking.
Selection Highlight
The highlight pass remains the last selection-specific render step. It looks up the active selection's current-frame block and tints exactly the cells the selection covers with the theme's selection style. With no active selection, the pass is inert, so normal pane and overlay rendering remains unchanged beneath it.
The final sprint was deliberately visual and additive. It did not revisit pane rendering or gesture routing; it consumed an already-live selection and applied the crate's highlight geometry after the frame was otherwise complete. The run facts show an additional successful gate after this sprint, so the finished stack was checked once more at the boundary where the visual post-pass completed the feature.