• Fix a route being able to write its index.html outside the output directory. A route is turned into a path under --out, but normalizeRoute only ensured a single leading slash: a .. segment (../secret) wrote above the output directory, and a leading // (//etc/passwd) became an absolute path that path.join honoured, discarding --out entirely. This was reachable from a plain routes file or a YAML config, not only --crawl, and had been present since 0.1.0. normalizeRoute now rejects both shapes; discovered crawl links that would traverse are skipped rather than aborting the crawl; and the writer refuses any target outside the output directory as a second layer. Ordinary routes, and a safe absolute link like /../about that cannot climb above root, are unaffected.

• Fix --crawl aborting the whole run and discarding every page already rendered when it followed a same-origin link to something that is not a Flutter route, such as a PDF or an image linked from the site's own nav or footer. The browser capturer already treats an empty semantics tree and empty rendered text as "this page never booted a Flutter app" and throws; the engine now catches that per route instead of letting it escape run() and take down the whole prerender. Every route rendered before the failure keeps its file and its sitemap entry.
• The failed route is recorded in the new PrerenderResult.failedRoutes, printed in the CLI summary, and reported as a warning on stderr. --fail-on-empty also exits non-zero when a route failed to capture.

• Add --crawl, which discovers routes by following the in-page links the engine already recovers instead of prerendering only the listed routes. The routes you pass (or / when you pass none) seed a work queue, every same-origin link found on a page is normalised and enqueued if it has not been seen, and the crawl stops at --max-pages (default 100). Off-site links, mailto:/tel:, and bare fragments are skipped; an absolute URL is followed only when its origin matches --base-url. Without --crawl nothing changes: the tool still prerenders exactly the routes you list.
• The sitemap now lists the pages that were actually prerendered rather than the configured route list, so a crawl's discovered pages are included. For a fixed route list the output is the same as before.

• Shorten the screenshot description. pub.flutter-io.cn accepts up to 200 characters but scores only those under 160, so the previous release published cleanly and quietly gave up the documentation points it was meant to earn.

• Declare the diagram in pubspec.yaml so pub.flutter-io.cn renders it on the package page. It was already in the repository and the README, but pub.flutter-io.cn shows only what the screenshots: field points at.

• Add --robots, which writes a robots.txt declaring the generated sitemap. The tool produced a sitemap.xml that nothing pointed at; the Sitemap: directive is the documented way to announce one and is what webmaster tools and non-Google crawlers read. The line is only written when a sitemap was actually produced, so a crawler is never sent to a URL that would 404.
• The flag is off by default and never replaces an existing robots.txt. A project that ships web/robots.txt has it copied into the build, and silently overwriting crawl rules somebody wrote on purpose would be a worse bug than not writing the file; the existing one is left alone and the run reports it as a warning.
• Fix dart analyze reporting dozens of errors on a clean checkout. The example is a Flutter app, so the package's pure-Dart analyzer could not resolve any widget in it and called every one undefined. It is excluded from the package's analysis and still checked on its own terms with cd example && flutter analyze.

• Docs: make clear up front that this is a command-line tool you run against a flutter build web output, not a package you add to an app's dependencies. Also clarifies why pub.flutter-io.cn lists the platforms the tool runs on (Linux, macOS, Windows) rather than web.

• Docs: tightened the README wording and visuals.

Changelog #

Initial release.

• CLI (flutter_prerender) that prerenders a flutter build web output to static, crawlable HTML, one file per route.
• Recovers headings, paragraphs, links and image alt text from Flutter's accessibility tree without changing app source.
• Injects <title>, meta description, canonical, Open Graph, Twitter Card and optional JSON-LD per route.
• Generates sitemap.xml.
• Parity guard that compares the generated HTML against Flutter's own accessibility text and warns (or fails, with --fail-on-parity) on injected content.
• Warnings for routes that recover no content (--fail-on-empty to make it fatal) and for routes that duplicate another route's content.
• YAML config file and command-line flags, with flags overriding the file. Invalid numeric flags are rejected instead of silently ignored.