fix(tui): replace scroll debounce with batch detection and absolute position indexing#88
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yishuiliunian merged 1 commit intomainfrom Apr 6, 2026
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…nd absolute position indexing (#85) The 30ms async timer debounce had race conditions between ArrowDebounceTimeout and event batch processing, causing scroll/history misfires. The tail-window rendering model drifted during output because window_size depended on scroll_offset, creating a feedback loop. Changes: - Delete scroll_debounce.rs (197 lines) and all timer machinery - Batch detection in tui_loop: ≥2 arrows in one batch = mouse wheel → scroll; 1 arrow = keyboard → history. No timers, no races. - ContentScroll struct encapsulates offset + prev_total + LineCache with reset()/to_bottom()/scroll_up()/scroll_down() methods - Absolute position indexing via slice() replaces tail() feedback loop; offset auto-compensated on content growth while pinned - E2E regression tests for both bugs + unit tests for compensation logic
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…terministic scroll detection (#88) The previous approach used xterm alternate scroll mode (\x1b[?1007h) to convert mouse wheel events into Up/Down arrow key sequences, then relied on batch-counting heuristics (≥2 arrows per batch = scroll) to distinguish scroll from keyboard input. This was fundamentally unreliable across different terminal emulators and system load conditions. Switch to crossterm's EnableMouseCapture which provides actual MouseEvent::ScrollUp/ScrollDown events, making the distinction deterministic. Up/Down arrow keys now always route to history navigation.
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* fix(tui): replace alternate scroll heuristic with MouseCapture for deterministic scroll detection (#88) The previous approach used xterm alternate scroll mode (\x1b[?1007h) to convert mouse wheel events into Up/Down arrow key sequences, then relied on batch-counting heuristics (≥2 arrows per batch = scroll) to distinguish scroll from keyboard input. This was fundamentally unreliable across different terminal emulators and system load conditions. Switch to crossterm's EnableMouseCapture which provides actual MouseEvent::ScrollUp/ScrollDown events, making the distinction deterministic. Up/Down arrow keys now always route to history navigation. * fix: rustfmt module ordering in suite.rs
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Summary
tail()feedback loop with absolute position indexing viaslice(), auto-compensating offset on content growthContentScrollstruct encapsulating scroll offset + compensation state + line cache with cleanreset()/to_bottom()/scroll_up()/scroll_down()APIChanges
scroll_debounce.rs(197 lines) — entire async timer state machinecontent_scroll.rs—ContentScrollstruct with render + compensation logictui_loop.rs(batch pre-scan),input/mod.rs(Up/Down → direct history),app/mod.rs(3 fields → 1 struct),render.rs,key_dispatch.rs,key_dispatch_ops.rs,navigation.rs,event.rs,actions.rs,line_cache.rs,progress/mod.rse2e_scroll_test.rs(3 regression tests),scroll_compensation_test.rs(4 unit tests), updated 5 existing test filesTest plan
bazel test //crates/loopal-tui:loopal-tui_test— 377 tests passbazel build //... --config=clippy— zero warningsbazel build //... --config=rustfmt— clean