`Uncaught DOMException: String contains an invalid character` on nightly-rustc docs search

[zachs18]

Reproduction Steps

Go to the nightly compiler's API docs https://doc.rust-lang.org/nightly/nightly-rustc and search for something, e.g. https://doc.rust-lang.org/nightly/nightly-rustc/?search=PolyExistentialTraitRef

Expected Outcome

The search completes with no Javascript error, like it does on beta and stable:
https://doc.rust-lang.org/beta/nightly-rustc/?search=PolyExistentialTraitRef

https://doc.rust-lang.org/stable/nightly-rustc/?search=PolyExistentialTraitRef

Actual Output

On Firefox, Chromium, and GNOME Web (all on Ubuntu), the search results never appear. In Firefox's Javascript console, an error message Uncaught DOMException: String contains an invalid character occurs. In Chromium's Javascript console, a similar error occurs Uncaught InvalidCharacterError: Failed to execute 'atob' on 'Window': The string to be decoded is not correctly encoded.

Firefox JS error backtrace

Uncaught DOMException: String contains an invalid character
    RoaringBitmap https://doc.rust-lang.org/nightly/nightly-rustc/static.files/search-6c528b5c.js:1
    buildIndex https://doc.rust-lang.org/nightly/nightly-rustc/static.files/search-6c528b5c.js:1
    DocSearch https://doc.rust-lang.org/nightly/nightly-rustc/static.files/search-6c528b5c.js:1
    initSearch https://doc.rust-lang.org/nightly/nightly-rustc/static.files/search-6c528b5c.js:6
     https://doc.rust-lang.org/nightly/nightly-rustc/search-index.js:3
[search-6c528b5c.js:1](https://doc.rust-lang.org/nightly/nightly-rustc/static.files/search-6c528b5c.js)
    RoaringBitmap https://doc.rust-lang.org/nightly/nightly-rustc/static.files/search-6c528b5c.js:1
    buildIndex https://doc.rust-lang.org/nightly/nightly-rustc/static.files/search-6c528b5c.js:1
    DocSearch https://doc.rust-lang.org/nightly/nightly-rustc/static.files/search-6c528b5c.js:1
    initSearch https://doc.rust-lang.org/nightly/nightly-rustc/static.files/search-6c528b5c.js:6
     https://doc.rust-lang.org/nightly/nightly-rustc/search-index.js:3

Chromium JS error backtrace

Uncaught InvalidCharacterError: Failed to execute 'atob' on 'Window': The string to be decoded is not correctly encoded.
    at new RoaringBitmap (search-6c528b5c.js:1:16717)
    at DocSearch.buildIndex (search-6c528b5c.js:1:28524)
    at new DocSearch (search-6c528b5c.js:1:22924)
    at initSearch (search-6c528b5c.js:6:18434)
    at search-index.js:3:36

Version

logo
Rustdoc
1.91.0-nightly
(1ebbd87 2025-08-11)

Firefox 141.0.3 (64-bit)

Chromium Version 138.0.7204.183 (Official Build) snap (64-bit)

GNOME Web 46.5

Additional Details

The issue does not happen for me for locally-built docs with ./x.py doc compiler --open (even on the same commit 1ebbd87).

[Zalathar]

Possibly related to #141658, which recently added the .u field that appears to be missing in the search index entries.

[fmease]

cc @lolbinarycat @GuillaumeGomez

[GuillaumeGomez]

Taking a look.

[GuillaumeGomez]

Opened #145349.