fix: address GhostMaps resource and source ownership review findings

src/layers/ghostMaps/lifecycle.test.mjs

@@ -0,0 +1,180 @@
+import assert from 'node:assert/strict';
+import test from 'node:test';
+import * as Cesium from 'cesium';
+import { createGhostMapsLayer } from './index.js';
+
+function element(localName, children = [], value = '', attributes = {}) {
+  const node = {
+    localName,
+    children,
+    get textContent() {
+      return value + children.map((child) => child.textContent).join('');
+    },
+    getAttribute: (key) => attributes[key] ?? null,
+    getElementsByTagName(name) {
+      return children.flatMap((child) => [
+        ...(name === '*' || name === child.localName ? [child] : []),
+        ...child.getElementsByTagName(name),
+      ]);
+    },
+  };
+  for (const child of children) child.parentElement = node;
+  return node;
+}
+
+function documentFixture() {
+  return element('document', [
+    element('kml', [
+      element('Document', [
+        element(
+          'Style',
+          [
+            element('IconStyle', [
+              element('Icon', [element('href', [], 'icon.png')]),
+            ]),
+          ],
+          '',
+          { id: 'pin' },
+        ),
+        element('Placemark', [
+          element('name', [], 'Test report'),
+          element('styleUrl', [], '#pin'),
+          element('Point', [element('coordinates', [], '12,34')]),
+        ]),
+      ]),
+    ]),
+  ]);
+}
+
+// A stored KMZ with a local icon; the XML DOM double supplies its one point.
+function fixtureKmz() {
+  const files = [
+    ['doc.kml', '<kml/>'],
+    ['icon.png', 'packed icon'],
+  ];
+  const local = [];
+  const central = [];
+  let offset = 0;
+  for (const [name, value] of files) {
+    const key = Buffer.from(name);
+    const bytes = Buffer.from(value);
+    const header = Buffer.alloc(30);
+    header.writeUInt32LE(0x04034b50);
+    header.writeUInt32LE(bytes.length, 18);
+    header.writeUInt32LE(bytes.length, 22);
+    header.writeUInt16LE(key.length, 26);
+    const directory = Buffer.alloc(46);
+    directory.writeUInt32LE(0x02014b50);
+    directory.writeUInt32LE(bytes.length, 20);
+    directory.writeUInt32LE(bytes.length, 24);
+    directory.writeUInt16LE(key.length, 28);
+    directory.writeUInt32LE(offset, 42);
+    local.push(header, key, bytes);
+    central.push(directory, key);
+    offset += header.length + key.length + bytes.length;
+  }
+  const directory = Buffer.concat(central);
+  const end = Buffer.alloc(22);
+  end.writeUInt32LE(0x06054b50);
+  end.writeUInt16LE(files.length, 8);
+  end.writeUInt16LE(files.length, 10);
+  end.writeUInt32LE(directory.length, 12);
+  end.writeUInt32LE(offset, 16);
+  return new Uint8Array(Buffer.concat([...local, directory, end]));
+}
+
+function fixture(t, { beforeFileReturns, onCreateUrl } = {}) {
+  const previous = Object.getOwnPropertyDescriptor(globalThis, 'DOMParser');
+  globalThis.DOMParser = class {
+    parseFromString() {
+      return documentFixture();
+    }
+  };
+  t.after(() => {
+    if (previous) Object.defineProperty(globalThis, 'DOMParser', previous);
+    else delete globalThis.DOMParser;
+  });
+  const created = [];
+  const revoked = [];
+  t.mock.method(URL, 'createObjectURL', () => {
+    const url = `blob:local-${created.length}`;
+    created.push(url);
+    onCreateUrl?.(layer);
+    return url;
+  });
+  t.mock.method(URL, 'revokeObjectURL', (url) => revoked.push(url));
+  t.mock.method(console, 'warn', () => {});
+  const mounted = new Set();
+  const viewer = {
+    scene: { requestRender() {} },
+    dataSources: {
+      async add(dataSource) {
+        mounted.add(dataSource);
+        return dataSource;
+      },
+      remove(dataSource) {
+        return mounted.delete(dataSource);
+      },
+    },
+  };
+  const layer = createGhostMapsLayer({
+    storage: null,
+    source: {
+      getCatalog: async () => ({
+        products: [{ id: 'cip', version: 'a'.repeat(40), defaultOn: true }],
+      }),
+      getFile: async () => {
+        beforeFileReturns?.(layer);
+        return fixtureKmz();
+      },
+    },
+  });
+  layer.init(viewer);
+  layer.enable();
+  t.after(() => layer.destroy());
+  return { layer, viewer, mounted, created, revoked };
+}
+
+test('cancelling a file read does not allocate packed-image URLs', async (t) => {
+  const { layer, viewer, mounted, created, revoked } = fixture(t, {
+    beforeFileReturns: (layer) => queueMicrotask(() => layer.disable()),
+  });
+  await layer.update(viewer);
+  assert.equal(created.length, 0);
+  assert.equal(revoked.length, 0);
+  assert.equal(mounted.size, 0);
+});
+
+test('cancellation during parsing releases every packed-image URL', async (t) => {
+  const { layer, viewer, mounted, created, revoked } = fixture(t, {
+    onCreateUrl: (layer) => layer.disable(),
+  });
+  await layer.update(viewer);
+  assert.equal(created.length, 1);
+  assert.deepEqual(revoked, created);
+  assert.equal(mounted.size, 0);
+});
+
+test('entity construction failure releases parsed image URLs', async (t) => {
+  const { layer, viewer, mounted, created, revoked } = fixture(t);
+  t.mock.method(Cesium.EntityCollection.prototype, 'add', () => {
+    throw new Error('fixture entity failure');
+  });
+  await layer.update(viewer);
+  assert.equal(created.length, 1);
+  assert.deepEqual(revoked, created);
+  assert.equal(mounted.size, 0);
+  assert.equal(layer.getStats().error, 'fixture entity failure');
+});
+
+test('successful load keeps icons until the product is disabled', async (t) => {
+  const { layer, viewer, mounted, created, revoked } = fixture(t);
+  await layer.update(viewer);
+  assert.equal(created.length, 1);
+  assert.equal(revoked.length, 0);
+  assert.equal(mounted.size, 1);
+  assert.equal(layer.getStats().count, 1);
+  layer.disable();
+  assert.deepEqual(revoked, created);
+  assert.equal(mounted.size, 0);
+});