[Init] Initial commit - NetMesh terminal manager

components/terminal/selectionOverlayPosition.test.ts

@@ -0,0 +1,83 @@
+import test from "node:test";
+import assert from "node:assert/strict";
+import { resolveSelectionOverlayPosition } from "./useTerminalEffects";
+
+function createRect(left: number, top: number, width: number, height: number) {
+  return {
+    left,
+    top,
+    right: left + width,
+    bottom: top + height,
+    width,
+    height,
+    x: left,
+    y: top,
+    toJSON: () => ({}),
+  };
+}
+
+function createContainer(offsetTop = 30) {
+  const screen = {
+    clientWidth: 800,
+    clientHeight: 400,
+    getBoundingClientRect: () => createRect(10, 20, 800, 400),
+  };
+  return {
+    clientWidth: 1000,
+    clientHeight: 600,
+    offsetLeft: 0,
+    offsetTop,
+    querySelector: () => screen,
+    getBoundingClientRect: () => createRect(0, 0, 1000, 600),
+  } as unknown as HTMLElement;
+}
+
+function createTerm(range: { start: { x: number; y: number }; end: { x: number; y: number } }, viewportY = 5) {
+  return {
+    rows: 20,
+    cols: 80,
+    buffer: {
+      active: {
+        viewportY,
+      },
+    },
+    getSelection: () => "selected output",
+    getSelectionPosition: () => range,
+  };
+}
+
+test("resolveSelectionOverlayPosition anchors to the top-right of a single-line selection", () => {
+  const position = resolveSelectionOverlayPosition(
+    createTerm({ start: { x: 5, y: 10 }, end: { x: 15, y: 10 } }),
+    createContainer(),
+  );
+
+  assert.deepEqual(position, { left: 168, top: 142 });
+});
+
+test("resolveSelectionOverlayPosition anchors multi-line selections to the visible row right edge", () => {
+  const position = resolveSelectionOverlayPosition(
+    createTerm({ start: { x: 4, y: 12 }, end: { x: 20, y: 14 } }, 10),
+    createContainer(),
+  );
+
+  assert.deepEqual(position, { left: 818, top: 82 });
+});
+
+test("resolveSelectionOverlayPosition clamps near the top edge", () => {
+  const position = resolveSelectionOverlayPosition(
+    createTerm({ start: { x: 1, y: 5 }, end: { x: 4, y: 5 } }),
+    createContainer(0),
+  );
+
+  assert.equal(position?.top, 36);
+});
+
+test("resolveSelectionOverlayPosition returns null when the selected row is offscreen", () => {
+  const position = resolveSelectionOverlayPosition(
+    createTerm({ start: { x: 1, y: 2 }, end: { x: 4, y: 2 } }, 5),
+    createContainer(),
+  );
+
+  assert.equal(position, null);
+});