GTK tab switcher: migrate to quadraui::gtk::draw_list with rounded border

[JDonaghy]

Summary

The GTK tab-switcher popup is bespoke (src/gtk/draw.rs:2801::draw_tab_switcher_popup) and draws a square 1-pixel stroked border, while the TUI version uses quadraui::tui::draw_list with bordered = true and renders rounded ╭─╮ ╰─╯ corners. Surfaced during smoke-testing of the #223 ListView rasteriser pilot — the visual divergence is pre-existing, not introduced by the pilot, but it stands out now that the TUI version got migrated.

Two-step fix

1. Add bordered support to quadraui::gtk::draw_list. The current public rasteriser (in quadraui/src/gtk/list.rs) explicitly comments that list.bordered isn't honoured. Add:

   • Rounded-rectangle border via Cairo arcs (3-4 px corner radius, matching dialog / palette modal styling).
   • Title overlay on the top border (single-row label centred or left-padded), using theme.title_fg and a small inset background block to "cut" the border behind the title. The TUI version's title-as-" {title} " pattern is the visual reference.
   • Inset the item region by 1 cell / row-height equivalent on each side so item rows don't overlap the border.

2. Migrate draw_tab_switcher_popup to call quadraui::gtk::draw_list with bordered = true. The bespoke render code goes away; vimcode just builds the ListView (already exists via render::tab_switcher_to_quadraui_list_view) and passes it through. This deletes ~80 lines of vimcode-private rendering and aligns with the TUI behaviour.

Files

• quadraui/src/gtk/list.rs — bordered branch
• src/gtk/draw.rs:2801 — draw_tab_switcher_popup, becomes a thin wrapper

Surfaced by

#223 ListView rasteriser pilot (Session 332 smoke test).

Related

• Lift TUI + GTK rasterisers out of vimcode and into the quadraui crate #223 — overall arc, ListView pilot 3 commit
• Dialog primitive: per-backend native-look styling option #209 — Dialog primitive native-look styling (similar shape: bordered surface needs Cairo-native polish on GTK)

[JDonaghy]

Implementation notes (2026-05-16)

Prereq landed: quadraui's GTK list rasteriser now supports bordered = true (rounded-rect border, 3px corner radius, title overlay with background knockout). Pull quadraui before starting: cd ~/src/quadraui && git pull

What to do:

1. Delete the bespoke draw_tab_switcher_popup in src/gtk/draw.rs (~80 lines).
2. Replace with a call to quadraui::gtk::draw_list using the ListView already built by render::tab_switcher_to_quadraui_list_view. Set bordered = true.
3. Verify the title renders on the top border and items are inset correctly.

Files: src/gtk/draw.rs only.

Do NOT touch: src/tui_main/, src/core/engine/keys.rs (other agents are there).

[JDonaghy]

Status update (Session 384)

Vimcode-side wiring was already done in PR #162 (April): draw_tab_switcher_popup_list routes through b.draw_list and tab_switcher_to_quadraui_list_view already sets bordered: true. Pulling quadraui (commit 2d21169 from yesterday) was meant to flip the popup into rounded chrome mode automatically — but smoke test surfaced two real bugs in quadraui's new GTK bordered rasteriser:

• quadraui#207 — rounded corners not visible. gtk/list.rs:76-78 fills the full popup rect with base_bg BEFORE the rounded border is stroked, so the corner pixels outside the arc are still base_bg and the popup looks square.
• quadraui#208 — items overlap the title overlay. In bordered mode ListView::layout sets items_y_start = inset_y (1px), but the GTK rasteriser paints the title line_height tall (≈20px). The first item paints over the title.

Vimcode-side defensive fix landed on branch

31bdd86 on issue-225-tab-switcher-draw-list switches the layout to UI_FONT for the duration of the popup and explicitly calls b.set_current_theme() / b.set_current_line_height() instead of inheriting from an earlier scope (matches the pattern in draw_picker_popup / draw_tab_bar). This does NOT fix the visual bugs — those are quadraui — but it removes the only enter_frame_scope caller relying on inherited state.

Blocked on

quadraui#207 and quadraui#208. Once both land + are pulled, retest the popup; if it looks right out of the box, this issue closes with only the defensive font/theme commit. If anything else surfaces, follow up here.

[JDonaghy]

Unblocked (2026-05-17, coordinator)

quadraui#207 and #208 are both fixed and merged. Pull quadraui before resuming:

cd ~/src/quadraui && git pull

Then retest the issue-225-tab-switcher-draw-list branch — the bordered popup should now show rounded corners and items below the title. If it looks right, the branch is ready for smoke test / PR.