Incorrect promise logic

[mariuszdev]

https://developers.google.com/web/ilt/pwa/caching-files-with-service-worker#serving_files_from_the_cache

Cache then network example.

var networkDataReceived = false;

startSpinner();

// fetch fresh data
var networkUpdate = fetch('/data.json').then(function(response) {
  return response.json();
}).then(function(data) {
  networkDataReceived = true;
  updatePage(data);
});

// fetch cached data
caches.match('/data.json').then(function(response) {
  if (!response) throw Error("No data");
  return response.json();
}).then(function(data) {
  // don't overwrite newer network data
  if (!networkDataReceived) {
    updatePage(data);
  }
})
.catch(function() {
  // we didn't get cached data, the network is our last hope:
  return networkUpdate;
})
.catch(showErrorMessage) // never called, because previous catch swallows thrown error
.then(stopSpinner()); // stopSpinner called immediately, should be `then(stopSpinner)`.

See comments for last 2 lines of above snippet

If there is better place to report this problem, please let me know. I'll move it.

[DavidScales]

Sorry for the slow response. Yeah that doesn't look right to me, we are currently in a bit of publishing limbo but I will leave this open so I can make a fix once publishing is sorted. Thanks for reporting this!