fix(test): flaky test due to calling toJSON while hot updating

[stormslowly]

Problem

remove-dynamic-entry-with-loader

Panic during E2E testing

Message: should set in compilation first
Location: crates/rspack_core/src/utils/deref_option.rs:52

Root Cause Analysis

The problem occurs as follows:

0. The compiler completes the first compilation.
1. The test case asserts successfully, then modifies the file's content, triggering a page.reload.
2. This modification triggers a new compilation while the DerefOption<build_module_graph_artifact> is being executed.
3. The page.reload initiates a new HMR (Hot Module Replacement) connection to the development server. The server sends stats to the new HMR client, which triggers a stats.toJson() call that requires the module graph.
4. A panic occurs because the module graph is taken away.

Solution

1. Configure a single runtime chunk to use HMR for reloading the page once the compilation is completed.
2. Remove the page.reload in the test to avoid race conditions.

Related Links

Checklist

• Tests updated (or not required).
• Documentation updated (or not required).

[netlify]

✅ Deploy Preview for rspack canceled.

Name	Link
🔨 Latest commit	07e4398
🔍 Latest deploy log	https://app.netlify.com/projects/rspack/deploys/6961ab86b7f8020008769cb3

[github-actions]

📦 Binary Size-limit

Comparing 07e4398 to feat: add requireAlias option to control require variable renaming (#12686) by harpsealjs

🙈 Size remains the same at 47.88MB

[codspeed-hq]

CodSpeed Performance Report

Merging this PR will not alter performance

_{Comparing test/fix_flaky_dynamic_entry_by_loader (07e4398) with main (6ee0d4b)}

Summary

✅ 16 untouched benchmarks
⏩ 1 skipped benchmark¹

Footnotes

1. 1 benchmark was skipped, so the baseline result was used instead. If it was deleted from the codebase, click here and archive it to remove it from the performance reports. ↩

[github-actions]

Rsdoctor Bundle Diff Analysis

Found 5 projects in monorepo, 0 projects with changes.

📊 Quick Summary

Project	Total Size	Change
react-10k	5.7 MB	0
react-1k	825.4 KB	0
react-5k	2.7 MB	0
ui-components	2.1 MB	0
rome	984.3 KB	0

Generated by Rsdoctor GitHub Action

[Copilot]

Pull request overview

This PR fixes a flaky E2E test that was causing panics due to a race condition between page reload and HMR connection during compilation. The test was attempting to call stats.toJSON() while the module graph was being updated during hot module replacement, resulting in a panic.

Changes:

• Added runtimeChunk: 'single' optimization to ensure HMR uses a single runtime chunk
• Removed manual page.reload() call and replaced with direct HMR-based assertion to eliminate the race condition

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
tests/e2e/cases/make/remove-dynamic-entry-with-loader/rspack.config.js	Added runtimeChunk: 'single' optimization to enable proper HMR handling
tests/e2e/cases/make/remove-dynamic-entry-with-loader/index.test.ts	Replaced manual page reload with direct toContainText assertion that relies on HMR

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