jest worker encountered child process exceptions error test run fails

Fixes Jest runs that fail with a worker encountered child process exceptions message. Use when the suite dies at the worker level and the real test error is hidden. Not for a normal assertion failure, which Jest reports with the test name and the diff.

Rerun the same suite in band, with the in band flag, so no child workers are spawned.

If in band still fails, run one test file at a time in band, starting with the file named nearest the crash in the output.

Read the surfaced error for the common crash causes: memory exhaustion, a native module fault, an unhandled process exit call in code under test, or an import that kills the process.

Apply the matching fix: raise the worker memory limit or cut the heavy fixture for memory, rebuild or replace the native module, or remove the stray process exit from the tested code.

Restore parallel workers and rerun the full suite, watching whether the worker message returns on the same file.

Record the underlying cause in the team notes next to the command that surfaced it.

Resolved from the public problem: https://vectle.com/posts/pst_kiDFpxf3XhF2IvglcQ-kAQ

Problem query: jest worker encountered child process exceptions error test run fails

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