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Prefetch broken — `Cannot read property 'load' of undefined`

See original GitHub issue

Describe the bug Trying to prefetch a route programatically errors when trying to call load on the prefetched route

Logs

To Reproduce

Call prefetch on a route if browser is true

if (browser) {
  prefetch('/some-route')
}

Expected behavior Prefetch should work…

Information about your SvelteKit Installation:

Diagnostics

System:
    OS: macOS 11.2.1
    CPU: (4) x64 Intel(R) Core(TM) i5-7360U CPU @ 2.30GHz
    Memory: 684.30 MB / 16.00 GB
    Shell: 5.7.1 - /usr/local/bin/zsh
  Binaries:
    Node: 14.17.0 - /usr/local/bin/node
    Yarn: 1.22.4 - ~/.yarn/bin/yarn
    npm: 6.14.13 - /usr/local/bin/npm
  Browsers:
    Chrome: 91.0.4472.77
    Firefox: 74.0
    Safari: 14.0.3

Your browser: Chrome
Your adapter: adapter-static, though occurs in dev and preview as well

Severity Moderate — cannot use programatic prefetching to improve performance.

Issue Analytics

State:
Created 2 years ago
Reactions:1
Comments:9 (3 by maintainers)

Top GitHub Comments

1reaction

benmccanncommented, Aug 6, 2021

I think this might be fixed now. I just tried https://github.com/madeleineostoja/portfolio/tree/prefetch-bug with the latest version of SvelteKit and don’t see the error originally reported. Can you check if you’re still seeing this?

1reaction

xpycommented, Jul 6, 2021

manual prefetch happens before the Router is initialized and thus the this.renderer is undefined. Init of renderer happens here: https://github.com/sveltejs/kit/blob/master/packages/kit/src/runtime/client/router.js#L34 prefetch tries to access the renderer here: https://github.com/sveltejs/kit/blob/master/packages/kit/src/runtime/client/router.js#L217