Add automated typecheck for type definitions

Adds test/types.ts exercising the full public API surface, a typecheck
script running tsc --strict, and wires it into pretest alongside lint.
Also adds .eslintignore to skip .ts files and typescript as a devDep.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: danmactough

.eslintignore

@@ -0,0 +1 @@
+**/*.ts

package-lock.json

@@ -52,11 +52,13 @@
     "eslint": "^6.8.0",
     "iconv-lite": "^0.5.1",
     "mocha": "^7.1.2",
-    "node-fetch": "^2.6.0"
+    "node-fetch": "^2.6.0",
+    "typescript": "^5.9.3"
   },
   "scripts": {
     "lint": "eslint .",
-    "pretest": "npm run lint",
+    "typecheck": "tsc --noEmit --strict test/types.ts --lib es6 --module commonjs",
+    "pretest": "npm run lint && npm run typecheck",
     "test": "mocha",
     "version": "git changelog ; git add History.md"
   },

package.json

@@ -0,0 +1,77 @@
+import FeedParser = require('../index');
+
+// Constructor with no options
+const fp1 = new FeedParser();
+
+// Constructor with all options
+const fp2 = new FeedParser({
+  strict: false,
+  normalize: true,
+  addmeta: true,
+  feedurl: 'https://example.com/feed',
+  resume_saxerror: true,
+  MAX_BUFFER_LENGTH: 1024 * 1024,
+});
+
+// meta event
+fp2.on('meta', (meta: FeedParser.Meta) => {
+  const title: string = meta.title;
+  const description: string = meta.description;
+  const type: FeedParser.Type = meta['#type'];
+  const version: string = meta['#version'];
+  const ns: Array<{ [key: string]: string }> = meta['#ns'];
+  const attrs: { [key: string]: any } = meta['@'];
+  const date: Date | null = meta.date;
+  const pubdate: Date | null = meta.pubdate;
+  const link: string = meta.link;
+  const xmlurl: string = meta.xmlurl;
+  const author: string = meta.author;
+  const language: string = meta.language;
+  const image: FeedParser.Image = meta.image;
+  const imageUrl: string = image.url;
+  const favicon: string = meta.favicon;
+  const copyright: string = meta.copyright;
+  const generator: string = meta.generator;
+  const categories: string[] = meta.categories;
+  // namespace-prefixed properties via index signature
+  const itunesAuthor = meta['itunes:author'];
+});
+
+// error event
+fp2.on('error', (err: Error) => {
+  err.message;
+});
+
+// readable event + read()
+fp2.on('readable', () => {
+  let item: FeedParser.Item | null;
+  while ((item = fp2.read()) !== null) {
+    const title: string = item.title;
+    const description: string = item.description;
+    const summary: string = item.summary;
+    const date: Date | null = item.date;
+    const pubdate: Date | null = item.pubdate;
+    const link: string = item.link;
+    const origlink: string = item.origlink;
+    const author: string = item.author;
+    const guid: string = item.guid;
+    const comments: string = item.comments;
+    const image: { url: string } = item.image;
+    const categories: string[] = item.categories;
+    const source: FeedParser.Source = item.source;
+    const sourceTitle: string = source.title;
+    const sourceUrl: string = source.url;
+    const enclosures: FeedParser.Enclosure[] = item.enclosures;
+    const enc: FeedParser.Enclosure = enclosures[0];
+    const encUrl: string = enc.url;
+    const meta: FeedParser.Meta = item.meta;
+    // namespace-prefixed properties via index signature
+    const mediaContent = item['media:content'];
+  }
+});
+
+// once and addListener overloads
+fp2.once('meta', (_meta: FeedParser.Meta) => {});
+fp2.addListener('error', (_err: Error) => {});
+
+fp2.resumeSaxError();