fix border resizing ui

tests/pane-layout-store.test.ts

@@ -0,0 +1,101 @@
+/**
+ * pane-layout-store.test.ts — the shared pane-split store: splitPixels
+ * clamping, border moves that respect per-pane minimum widths, and
+ * commit() persistence into the app preferences.
+ */
+import { test, expect, beforeAll, afterAll } from "bun:test";
+import { mkdtempSync } from "node:fs";
+import { tmpdir } from "node:os";
+import { join } from "node:path";
+
+// Point the config dir at a throwaway directory BEFORE importing the store
+// (its module-level init reads it).
+process.env.XDG_CONFIG_HOME = mkdtempSync(join(tmpdir(), "podtui-panecfg-"));
+
+// The config dir must be set before the module is evaluated, so the app
+// store is loaded dynamically here rather than statically at the top.
+const { splitPixels, createPaneLayoutStore, DEFAULT_PANE_SPLITS } = await import(
+	"../src/stores/pane-layout"
+);
+const { useAppStore } = await import("../src/stores/app");
+
+beforeAll(async () => {
+	await useAppStore().whenReady();
+});
+afterAll(() => {
+	// Restore pristine preferences so a later file sharing this process
+	// (bun test reuses the module registry) renders the default split.
+	useAppStore().updatePreferences({ paneSplit: DEFAULT_PANE_SPLITS });
+});
+
+test("default splits mirror the historical 2:5:3 ratio at width 100", () => {
+	expect(DEFAULT_PANE_SPLITS).toEqual({ left: 0.2, right: 0.7 });
+	const { leftPx, rightPx } = splitPixels(100, DEFAULT_PANE_SPLITS);
+	expect(leftPx).toBe(20);
+	expect(rightPx).toBe(70);
+});
+
+test("splitPixels maps splits 1:1 to pixels (ratio exact at every width)", () => {
+	// Pure fraction→pixel mapping — no minimum enforcement in rendering.
+	expect(splitPixels(100, { left: 0.6, right: 0.7 })).toEqual({
+		leftPx: 60,
+		rightPx: 70,
+	});
+	expect(splitPixels(70, { left: 0.2, right: 0.7 })).toEqual({
+		leftPx: 14,
+		rightPx: 49,
+	});
+});
+
+test("splitPixels handles zero-width and degenerate terminals", () => {
+	expect(splitPixels(0, DEFAULT_PANE_SPLITS)).toEqual({ leftPx: 0, rightPx: 0 });
+	const tiny = splitPixels(40, { left: 0.2, right: 0.7 });
+	expect(tiny.leftPx).toBe(8);
+	expect(tiny.rightPx).toBe(28);
+});
+
+test("setRight clamps the preview to its minimum", () => {
+	const store = createPaneLayoutStore();
+	store.setRight(97, 100); // preview can't shrink below 15
+	expect(store.splits().right).toBeCloseTo(0.85, 5);
+	// The parent minimum also holds when the left border is dragged.
+	store.setLeft(1, 100);
+	expect(store.splits().left).toBeCloseTo(0.15, 5);
+});
+
+test("setLeft moves the border and normalizes stored fractions", () => {
+	const store = createPaneLayoutStore();
+	store.setLeft(40, 100);
+	expect(store.splits().left).toBeCloseTo(0.4, 5);
+	expect(store.splits().right).toBeCloseTo(0.7, 5);
+});
+
+test("setLeft below the parent minimum clamps up", () => {
+	const store = createPaneLayoutStore();
+	store.setLeft(5, 100);
+	expect(store.splits().left).toBeCloseTo(0.15, 5);
+});
+
+test("setLeft beyond the current minimum forces the right border right", () => {
+	const store = createPaneLayoutStore();
+	store.setLeft(60, 100);
+	expect(store.splits().left).toBeCloseTo(0.55, 5);
+	expect(store.splits().right).toBeCloseTo(0.85, 5);
+});
+
+test("setRight respects the current and preview minimums", () => {
+	const store = createPaneLayoutStore();
+	store.setRight(80, 100);
+	expect(store.splits().right).toBeCloseTo(0.8, 5);
+	store.setRight(40, 100); // must not cross below leftPx(20) + minCurrent(30)
+	expect(store.splits().right).toBeCloseTo(0.5, 5);
+});
+
+test("commit persists the split into the app preferences", async () => {
+	const store = createPaneLayoutStore();
+	store.setLeft(35, 100);
+	store.commit();
+	await useAppStore().whenReady();
+	expect(useAppStore().state().preferences.paneSplit.left).toBeCloseTo(0.35, 5);
+	expect(useAppStore().state().preferences.paneSplit.right).toBeCloseTo(0.7, 5);
+});