fix: reclaim wasted rows below the shortcut footer

src/ui/View.tsx

@@ -9,6 +9,7 @@ import { useProcessManager } from "../hooks/useProcessManager";
 import { ProgramStateProvider, useProgramState, ProgramStatus } from "../hooks/useProgramState";
 import { Colors } from "../lib/Colors";
 import type { CurseConfig } from "../parser";
+import { MIN_LOG_PREVIEW_HEIGHT, PROCESS_TABLE_OVERHEAD, VIEW_HEADER_HEIGHT } from "./layout";
 import { LogPage } from "./views/LogPage";
 import { MainPage, type DisplayMode } from "./views/MainPage";
 
@@ -32,7 +33,9 @@ function View(props: { config: CurseConfig }) {
 
 	const terminalHeight = stdout?.rows ?? 24;
 	const processCount = processesRef.current.length;
-	const normalMinHeight = processCount + 13; // header(4) + table(N+3) + logPreview(5) + footer(1)
+	// header + processTable(N + overhead) + minLogPreview + collapsed footer (1 row)
+	const normalMinHeight =
+		VIEW_HEADER_HEIGHT + processCount + PROCESS_TABLE_OVERHEAD + MIN_LOG_PREVIEW_HEIGHT + 1;
 	const compactMinHeight = processCount + 1;
 	const displayMode: DisplayMode =
 		terminalHeight < compactMinHeight

src/ui/components/ShortcutFooter.tsx

@@ -1,6 +1,10 @@
 import { Box, Text, useStdout } from "ink";
 
 import { Colors } from "../../lib/Colors";
+import { getShortcutFooterColumns, getShortcutFooterHeight } from "../layout";
+
+// Re-export so existing callers can keep importing it from this module.
+export { getShortcutFooterHeight };
 
 interface ShortcutFooterProps {
 	shortcuts: string[];
@@ -15,13 +19,7 @@ export function ShortcutFooter({ shortcuts, showShortcuts }: ShortcutFooterProps
 		<Box marginLeft={1} flexDirection="row">
 			{showShortcuts ? (
 				(() => {
-					// Calculate number of columns based on terminal width
-					let numColumns;
-					if (terminalWidth < 80) numColumns = 1;
-					else if (terminalWidth < 120) numColumns = 2;
-					else if (terminalWidth < 160) numColumns = 3;
-					else numColumns = 4;
-
+					const numColumns = getShortcutFooterColumns(terminalWidth);
 					const itemsPerColumn = Math.ceil(shortcuts.length / numColumns);
 
 					const columns = [];
@@ -49,20 +47,3 @@ export function ShortcutFooter({ shortcuts, showShortcuts }: ShortcutFooterProps
 		</Box>
 	);
 }
-
-// Helper function to calculate the height taken by shortcuts
-export function getShortcutFooterHeight(
-	shortcutsCount: number,
-	terminalWidth: number,
-	showShortcuts: boolean,
-): number {
-	if (!showShortcuts) return 0;
-
-	let numColumns;
-	if (terminalWidth < 80) numColumns = 1;
-	else if (terminalWidth < 120) numColumns = 2;
-	else if (terminalWidth < 160) numColumns = 3;
-	else numColumns = 4;
-
-	return Math.ceil(shortcutsCount / numColumns);
-}

src/ui/layout.test.ts

@@ -0,0 +1,258 @@
+import { describe, it, expect } from "bun:test";
+
+import {
+	computeLogPageLayout,
+	computeMainPageLayout,
+	getShortcutFooterColumns,
+	getShortcutFooterHeight,
+	LOG_PAGE_TITLE_HEIGHT,
+	MIN_LOG_PREVIEW_HEIGHT,
+	PROCESS_TABLE_OVERHEAD,
+	SEARCH_BAR_HEIGHT,
+	VIEW_HEADER_HEIGHT,
+} from "./layout";
+
+describe("getShortcutFooterColumns", () => {
+	it("uses 1 column when terminalWidth < 80", () => {
+		expect(getShortcutFooterColumns(40)).toBe(1);
+		expect(getShortcutFooterColumns(79)).toBe(1);
+	});
+
+	it("uses 2 columns for 80 <= width < 120", () => {
+		expect(getShortcutFooterColumns(80)).toBe(2);
+		expect(getShortcutFooterColumns(119)).toBe(2);
+	});
+
+	it("uses 3 columns for 120 <= width < 160", () => {
+		expect(getShortcutFooterColumns(120)).toBe(3);
+		expect(getShortcutFooterColumns(159)).toBe(3);
+	});
+
+	it("uses 4 columns for width >= 160", () => {
+		expect(getShortcutFooterColumns(160)).toBe(4);
+		expect(getShortcutFooterColumns(400)).toBe(4);
+	});
+});
+
+describe("getShortcutFooterHeight", () => {
+	// Regression: getShortcutFooterHeight previously returned 0 when shortcuts
+	// were collapsed, but the footer always renders the "? for shortcuts" row.
+	// That mismatch wasted 1 terminal row at the bottom of the screen.
+	it("returns 1 when shortcuts are hidden (the '? for shortcuts' row)", () => {
+		expect(getShortcutFooterHeight(9, 80, false)).toBe(1);
+		expect(getShortcutFooterHeight(0, 80, false)).toBe(1);
+		expect(getShortcutFooterHeight(20, 200, false)).toBe(1);
+	});
+
+	it("returns ceil(count / columns) when shortcuts are shown", () => {
+		// 80 width => 2 columns, 9 shortcuts => ceil(9 / 2) = 5
+		expect(getShortcutFooterHeight(9, 80, true)).toBe(5);
+		// 120 width => 3 columns, 9 shortcuts => 3
+		expect(getShortcutFooterHeight(9, 120, true)).toBe(3);
+		// 160 width => 4 columns, 9 shortcuts => 3
+		expect(getShortcutFooterHeight(9, 160, true)).toBe(3);
+		// 60 width => 1 column, 12 shortcuts => 12
+		expect(getShortcutFooterHeight(12, 60, true)).toBe(12);
+	});
+});
+
+describe("computeMainPageLayout", () => {
+	// Regression: previously the four heights summed to terminalHeight - 3,
+	// leaving three wasted rows at the bottom of the screen below the
+	// shortcut footer. The four sources of the gap were:
+	//   - headerHeight hardcoded to 4 (actual View header is 2 rows)
+	//   - an extra `- 1` safety buffer in the log preview height
+	//   - getShortcutFooterHeight returning 0 when collapsed (vs. 1 actual)
+	//   - LogPage's separate `6` constant being similarly miscounted
+	it("heights sum to terminalHeight when shortcuts are collapsed", () => {
+		const layout = computeMainPageLayout({
+			terminalHeight: 40,
+			terminalWidth: 120,
+			processCount: 5,
+			shortcutsCount: 9,
+			showShortcuts: false,
+		});
+		const total =
+			layout.headerHeight +
+			layout.processTableHeight +
+			layout.logPreviewHeight +
+			layout.shortcutFooterHeight;
+		expect(total).toBe(40);
+	});
+
+	it("heights sum to terminalHeight when shortcuts are expanded", () => {
+		const layout = computeMainPageLayout({
+			terminalHeight: 40,
+			terminalWidth: 120,
+			processCount: 5,
+			shortcutsCount: 9,
+			showShortcuts: true,
+		});
+		const total =
+			layout.headerHeight +
+			layout.processTableHeight +
+			layout.logPreviewHeight +
+			layout.shortcutFooterHeight;
+		expect(total).toBe(40);
+	});
+
+	it("uses correct fixed heights", () => {
+		const layout = computeMainPageLayout({
+			terminalHeight: 40,
+			terminalWidth: 120,
+			processCount: 5,
+			shortcutsCount: 9,
+			showShortcuts: false,
+		});
+		expect(layout.headerHeight).toBe(VIEW_HEADER_HEIGHT);
+		expect(layout.processTableHeight).toBe(5 + PROCESS_TABLE_OVERHEAD);
+		expect(layout.shortcutFooterHeight).toBe(1);
+	});
+
+	it("scales with process count and gives the rest to the log preview", () => {
+		const a = computeMainPageLayout({
+			terminalHeight: 40,
+			terminalWidth: 120,
+			processCount: 3,
+			shortcutsCount: 9,
+			showShortcuts: false,
+		});
+		const b = computeMainPageLayout({
+			terminalHeight: 40,
+			terminalWidth: 120,
+			processCount: 7,
+			shortcutsCount: 9,
+			showShortcuts: false,
+		});
+		expect(a.logPreviewHeight - b.logPreviewHeight).toBe(4);
+	});
+
+	it("expanding shortcuts shrinks the log preview by the same number of rows", () => {
+		const collapsed = computeMainPageLayout({
+			terminalHeight: 40,
+			terminalWidth: 120,
+			processCount: 3,
+			shortcutsCount: 9,
+			showShortcuts: false,
+		});
+		const expanded = computeMainPageLayout({
+			terminalHeight: 40,
+			terminalWidth: 120,
+			processCount: 3,
+			shortcutsCount: 9,
+			showShortcuts: true,
+		});
+		const footerDelta = expanded.shortcutFooterHeight - collapsed.shortcutFooterHeight;
+		expect(collapsed.logPreviewHeight - expanded.logPreviewHeight).toBe(footerDelta);
+	});
+
+	it("clamps the log preview to the minimum when the terminal is tight", () => {
+		const layout = computeMainPageLayout({
+			terminalHeight: 10, // very small
+			terminalWidth: 120,
+			processCount: 5,
+			shortcutsCount: 9,
+			showShortcuts: false,
+		});
+		expect(layout.logPreviewHeight).toBe(MIN_LOG_PREVIEW_HEIGHT);
+	});
+});
+
+describe("computeLogPageLayout", () => {
+	it("heights sum to terminalHeight when shortcuts are collapsed and not searching", () => {
+		const layout = computeLogPageLayout({
+			terminalHeight: 40,
+			terminalWidth: 120,
+			shortcutsCount: 12,
+			showShortcuts: false,
+			isSearchMode: false,
+		});
+		const total =
+			layout.headerHeight +
+			layout.titleHeight +
+			layout.searchBarHeight +
+			layout.logTableHeight +
+			layout.shortcutFooterHeight;
+		expect(total).toBe(40);
+	});
+
+	it("heights sum to terminalHeight when shortcuts are expanded", () => {
+		const layout = computeLogPageLayout({
+			terminalHeight: 40,
+			terminalWidth: 120,
+			shortcutsCount: 12,
+			showShortcuts: true,
+			isSearchMode: false,
+		});
+		const total =
+			layout.headerHeight +
+			layout.titleHeight +
+			layout.searchBarHeight +
+			layout.logTableHeight +
+			layout.shortcutFooterHeight;
+		expect(total).toBe(40);
+	});
+
+	it("heights sum to terminalHeight in search mode", () => {
+		const layout = computeLogPageLayout({
+			terminalHeight: 40,
+			terminalWidth: 120,
+			shortcutsCount: 12,
+			showShortcuts: false,
+			isSearchMode: true,
+		});
+		const total =
+			layout.headerHeight +
+			layout.titleHeight +
+			layout.searchBarHeight +
+			layout.logTableHeight +
+			layout.shortcutFooterHeight;
+		expect(total).toBe(40);
+		expect(layout.searchBarHeight).toBe(SEARCH_BAR_HEIGHT);
+	});
+
+	it("uses correct fixed heights", () => {
+		const layout = computeLogPageLayout({
+			terminalHeight: 40,
+			terminalWidth: 120,
+			shortcutsCount: 12,
+			showShortcuts: false,
+			isSearchMode: false,
+		});
+		expect(layout.headerHeight).toBe(VIEW_HEADER_HEIGHT);
+		expect(layout.titleHeight).toBe(LOG_PAGE_TITLE_HEIGHT);
+		expect(layout.searchBarHeight).toBe(0);
+		expect(layout.shortcutFooterHeight).toBe(1);
+	});
+
+	it("entering search mode reduces the log table by exactly one row", () => {
+		const inputs = {
+			terminalHeight: 40,
+			terminalWidth: 120,
+			shortcutsCount: 12,
+			showShortcuts: false,
+		};
+		const noSearch = computeLogPageLayout({ ...inputs, isSearchMode: false });
+		const searching = computeLogPageLayout({ ...inputs, isSearchMode: true });
+		expect(noSearch.logTableHeight - searching.logTableHeight).toBe(1);
+	});
+
+	it("expanding shortcuts shrinks the log table by the same number of rows", () => {
+		const collapsed = computeLogPageLayout({
+			terminalHeight: 40,
+			terminalWidth: 120,
+			shortcutsCount: 12,
+			showShortcuts: false,
+			isSearchMode: false,
+		});
+		const expanded = computeLogPageLayout({
+			terminalHeight: 40,
+			terminalWidth: 120,
+			shortcutsCount: 12,
+			showShortcuts: true,
+			isSearchMode: false,
+		});
+		const footerDelta = expanded.shortcutFooterHeight - collapsed.shortcutFooterHeight;
+		expect(collapsed.logTableHeight - expanded.logTableHeight).toBe(footerDelta);
+	});
+});