Collector fails with very large test counts (>> 100000)

[DerYeger]

Describe the bug

When a suite contains a huge number of tests (>> 100000), the collector's usage of the spread operator results in a "Maximum call stack size exceeded error".

Reproduction

Include a huge number of tests (e.g., using it.each).
See https://stackblitz.com/edit/vitest-dev-vitest-pf19qj?file=test%2Fsuite.test.ts.

System Info

System:
    OS: macOS 14.3.1
    CPU: (8) arm64 Apple M1
    Memory: 124.30 MB / 16.00 GB
    Shell: 5.9 - /bin/zsh
  Binaries:
    Node: 20.10.0 - ~/Library/Caches/fnm_multishells/20993_1708352067405/bin/node
    npm: 10.2.3 - ~/Library/Caches/fnm_multishells/20993_1708352067405/bin/npm
    pnpm: 8.15.1 - ~/Library/Caches/fnm_multishells/20993_1708352067405/bin/pnpm
    bun: 1.0.24 - ~/.bun/bin/bun
  Browsers:
    Chrome: 121.0.6167.184
    Safari: 17.3.1
  npmPackages:
    @vitest/coverage-v8: 1.2.2 => 1.2.2
    @vitest/ui: 1.2.2 => 1.2.2
    vitest: 1.2.2 => 1.2.2

Used Package Manager

pnpm

Validations

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• Read the Contributing Guidelines.
• Read the docs.
• Check that there isn't already an issue that reports the same bug to avoid creating a duplicate.
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• The provided reproduction is a minimal reproducible example of the bug.

[DerYeger]

See

vitest/packages/runner/src/utils/tasks.ts

Line 20 in e191e65

tests.push(...getTests(task))

[hi-ogawa]

Interesting find. It looks like this limitation is coming from runtime and people have especially have seen this when using Math.max(...) etc... https://stackoverflow.com/a/30834687

Just quick experiment on repl:

$ node
Welcome to Node.js v20.11.0.
Type ".help" for more information.
> [].push(...Array(1000000))
Uncaught RangeError: Maximum call stack size exceeded
> Math.max(...Array(1000000))
Uncaught RangeError: Maximum call stack size exceeded
> (() => {})(...Array(1000000))
Uncaught RangeError: Maximum call stack size exceeded
> [...Array(1000000)]
[
  undefined, undefined, undefined, undefined, undefined, undefined,
  ...
]

I think it would nice if we can avoid it, but there might be a few more places doing push(...someArray) where the size of someArray is proportional to the number of tests.

[DerYeger]

Interesting find. It looks like this limitation is coming from runtime and people have especially have seen this when using Math.max(...) etc... https://stackoverflow.com/a/30834687

Just quick experiment on repl:

$ node
Welcome to Node.js v20.11.0.
Type ".help" for more information.
> [].push(...Array(1000000))
Uncaught RangeError: Maximum call stack size exceeded
> Math.max(...Array(1000000))
Uncaught RangeError: Maximum call stack size exceeded
> (() => {})(...Array(1000000))
Uncaught RangeError: Maximum call stack size exceeded
> [...Array(1000000)]
[
  undefined, undefined, undefined, undefined, undefined, undefined,
  ...
]

I think it would nice if we can avoid it, but there might be a few more places doing push(...someArray) where the size of someArray is proportional to the number of tests.

I've validated the changes by patching the @vitest/runner package and successfully running the entirety of my test project's test suite.
I did not add a new test case in my PR because I'm unsure if you'd like to have ~150.000 empty tests just for this.