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test: stop DOM-element assertions from OOM-killing the worker

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`node:assert` builds its `AssertionError` eagerly, running `util.inspect`
over both operands with `depth: 1000`, `getters: true` and
`maxArrayLength: Infinity`. A React-rendered DOM element carries
`__reactFiber$*` / `__reactProps$*` as own enumerable properties, and that
fiber graph re-expands once per traversal path, so inspecting a single
rendered element allocates without bound. Measured on the Asset Library
heading: depth 6 = 1.3MB, 8 = 7.8MB, 10 = 36MB, 12 = 135MB -- at Node's
depth 1000 the worker dies before any `AssertionError` exists.

The damage is not the crash, it is the disguise. Equality assertions only
inspect their operands on failure, so these sites stayed invisible while
green and detonated exactly when the behaviour they guard regressed --
reporting as `worker exited unexpectedly` with a truncated count
(`8 passed (13)`) and no failing test named. Breaking the delete-path focus
restoration in `asset-library.tsx` reproduced it: 29.5GB anon-rss and the
system OOM killer, or a V8 heap abort in 3s under a 512MB cap. The same
regression now fails in 1.15s with `expect(element).toHaveFocus()` naming
both the expected heading and the `<body>` that took focus instead.

`expect` is not affected -- vitest prints and diffs DOM nodes through
pretty-format's DOM plugin, which reads tag/attributes/children and never
touches the fiber -- so every unsafe site converts to a matcher:
`toHaveFocus()` for the three focus comparisons, `not.toBeInTheDocument()`
for the sixteen `assert.equal(queryBy..., null)` absence checks, which are
equally lethal (proved separately: element-vs-null inspects the element).

Three layers so this cannot come back:
- the 20 live sites in asset-library/asset-picker now use matchers;
- `test-assertion-boundary/no-element-operand-equality` fails `pnpm lint`
  when a DOM-element expression reaches `node:assert` equality, resolving
  local bindings and exempting the forms that cannot fail with an element
  in hand (`assert.notEqual(el, null)`, `el.textContent`);
- a 2048MB worker old-space ceiling in `vitest.config.ts` bounds any future
  runaway to a legible `Reached heap limit` abort in seconds instead of an
  OOM-killed machine (heaviest suite peaks near 1.3GB RSS).

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
This commit is contained in:
DongHyeonka
2026-08-18 14:03:33 +09:00
co-authored by Claude Opus 5
parent 2483c4032f
commit b2f577ef49
4 changed files with 239 additions and 29 deletions
Download Patch File Download Diff File Expand all files Collapse all files
eslint.config.ts
+194
View File
@@ -382,6 +382,194 @@ const browserDataBoundaryPlugin = {
}, },
}; };
/**
* A DOM element rendered by React carries `__reactFiber$*` / `__reactProps$*`
* as *own enumerable* properties. `node:assert` builds its `AssertionError`
* eagerly, running `util.inspect` over both operands with `depth: 1000`,
* `getters: true` and `maxArrayLength: Infinity`; the fiber graph re-expands
* once per traversal path, so inspecting one rendered element allocates
* gigabytes and the worker dies before any `AssertionError` is ever thrown.
* A genuine regression then reports as an OOM or an opaque timeout instead of
* a failed assertion. Measured on this repo's Asset Library heading:
* depth 6 = 1.3MB, depth 8 = 7.8MB, depth 10 = 36MB, depth 12 = 135MB.
*
* Equality assertions only inspect their operands on failure, so an unsafe
* comparison stays invisible while green and detonates the day the behaviour
* it guards regresses -- which is exactly when the diagnosis is needed.
*
* `expect` is not affected: vitest prints and diffs through pretty-format's
* DOM plugin, which reads tag/attributes/children and never touches the fiber.
* So the safe form is always an `expect` matcher -- `toHaveFocus()`,
* `not.toBeInTheDocument()`, `toBe(element)` -- and this rule only forbids
* handing a DOM element to `node:assert`.
*/
const TESTING_LIBRARY_QUERY =
/^(get|query|find)(All)?By(Role|Text|LabelText|PlaceholderText|AltText|Title|DisplayValue|TestId)$/u;
const domQueryMethods = new Set([
"querySelector",
"querySelectorAll",
"getElementById",
"closest",
]);
const domElementProperties = new Set([
"activeElement",
"parentElement",
"firstElementChild",
"lastElementChild",
"nextElementSibling",
"previousElementSibling",
"offsetParent",
]);
// Fail when the operands *differ*, so on failure at least one element is
// still there to be inspected.
const positiveAssertEqualities = new Set([
"equal",
"strictEqual",
"deepEqual",
"deepStrictEqual",
]);
// Fail when the operands *match*. `assert.notEqual(element, null)` can only
// fail with `null` on both sides, so a nullish literal operand makes these
// safe; anything else leaves an element to inspect.
const negativeAssertEqualities = new Set([
"notEqual",
"notStrictEqual",
"notDeepEqual",
"notDeepStrictEqual",
]);
const noElementOperandEqualityRule: Rule.RuleModule = {
meta: {
type: "problem",
schema: [],
messages: {
unbounded:
"node:assert inspects both operands at depth 1000 to build its failure message, and a React-rendered element's __reactFiber$* graph exhausts the worker heap there, so the regression reports as an OOM instead of an assertion. Use an expect matcher instead -- expect(el).toHaveFocus(), expect(el).not.toBeInTheDocument(), expect(actual).toBe(expected) -- which prints DOM nodes through pretty-format's DOM plugin.",
},
},
create(context) {
const sourceCode = context.sourceCode;
const unwrap = (input: any): any => {
let node = input;
while (
node &&
[
"AwaitExpression",
"ChainExpression",
"TSAsExpression",
"TSNonNullExpression",
"TSSatisfiesExpression",
"TSTypeAssertion",
].includes(node.type)
) {
node = node.type === "AwaitExpression" ? node.argument : node.expression;
}
return node;
};
const memberName = (node: any): string | null => {
if (!node.computed && node.property?.type === "Identifier") {
return node.property.name;
}
if (
node.computed &&
(node.property?.type === "Literal" ||
node.property?.type === "StringLiteral") &&
typeof node.property.value === "string"
) {
return node.property.value;
}
return null;
};
const resolveInit = (node: any): any => {
const scope = sourceCode.getScope(node);
let current: any = scope;
while (current) {
const variable = current.variables.find(
(entry: any) => entry.name === node.name,
);
if (variable) {
const definition = variable.defs.at(-1);
return definition?.node?.type === "VariableDeclarator"
? definition.node.init
: null;
}
current = current.upper;
}
return null;
};
const isElementValued = (input: any, seen = new Set<any>()): boolean => {
const node = unwrap(input);
if (!node || seen.has(node)) return false;
seen.add(node);
if (node.type === "MemberExpression") {
const name = memberName(node);
return name !== null && domElementProperties.has(name);
}
if (node.type === "CallExpression") {
const callee = unwrap(node.callee);
if (callee?.type !== "MemberExpression") return false;
const name = memberName(callee);
return (
name !== null &&
(TESTING_LIBRARY_QUERY.test(name) || domQueryMethods.has(name))
);
}
if (node.type === "Identifier") {
return isElementValued(resolveInit(node), seen);
}
if (node.type === "ConditionalExpression") {
return (
isElementValued(node.consequent, seen) ||
isElementValued(node.alternate, seen)
);
}
return false;
};
const isNullish = (input: any): boolean => {
const node = unwrap(input);
if (!node) return false;
return (
(node.type === "Literal" && node.value === null) ||
(node.type === "Identifier" && node.name === "undefined")
);
};
return {
CallExpression(node: any) {
const callee = unwrap(node.callee);
if (callee?.type !== "MemberExpression") return;
const object = unwrap(callee.object);
if (object?.type !== "Identifier" || object.name !== "assert") return;
const name = memberName(callee);
if (name === null) return;
const positive = positiveAssertEqualities.has(name);
if (!positive && !negativeAssertEqualities.has(name)) return;
const operands = (node.arguments ?? []).slice(0, 2);
if (!positive && operands.some((argument: any) => isNullish(argument))) {
return;
}
const operand = operands.find((argument: any) =>
isElementValued(argument),
);
if (operand) context.report({ node: operand, messageId: "unbounded" });
},
};
},
};
const testAssertionBoundaryPlugin = {
rules: {
"no-element-operand-equality": noElementOperandEqualityRule,
},
};
const commonLanguageOptions = { const commonLanguageOptions = {
ecmaVersion: "latest", ecmaVersion: "latest",
sourceType: "module", sourceType: "module",
@@ -811,6 +999,12 @@ export default [
...globals.node, ...globals.node,
}, },
}, },
plugins: {
"test-assertion-boundary": testAssertionBoundaryPlugin,
},
rules: {
"test-assertion-boundary/no-element-operand-equality": "error",
},
}, },
{ {
files: [`tests/support/browser/**/*.${sourceExtensions}`], files: [`tests/support/browser/**/*.${sourceExtensions}`],
tests/features/tech-log/asset-library.test.tsx
+20 -19
View File
@@ -1,7 +1,7 @@
// @vitest-environment jsdom // @vitest-environment jsdom
import assert from "node:assert/strict"; import assert from "node:assert/strict";
import { test } from "vitest"; import { expect, test } from "vitest";
import { act, render, screen, waitFor } from "@testing-library/react"; import { act, render, screen, waitFor } from "@testing-library/react";
import userEvent from "@testing-library/user-event"; import userEvent from "@testing-library/user-event";
@@ -132,7 +132,7 @@ test("shows archive instead of delete for an asset in use", async () => {
await user.click(await screen.findByRole("button", { name: "boundary" })); await user.click(await screen.findByRole("button", { name: "boundary" }));
assert.ok(await screen.findByRole("button", { name: "보관" })); assert.ok(await screen.findByRole("button", { name: "보관" }));
assert.equal(screen.queryByRole("button", { name: "삭제" }), null); expect(screen.queryByRole("button", { name: "삭제" })).not.toBeInTheDocument();
}); });
test("surfaces ASSET_IN_USE when the server rejects a delete", async () => { test("surfaces ASSET_IN_USE when the server rejects a delete", async () => {
@@ -216,7 +216,7 @@ test("removes the asset and restores focus to the page heading, not the detached
const options = deleteCalls[0].options as { idempotencyKey?: unknown }; const options = deleteCalls[0].options as { idempotencyKey?: unknown };
assert.equal(typeof options.idempotencyKey, "string"); assert.equal(typeof options.idempotencyKey, "string");
assert.ok((options.idempotencyKey as string).length > 0); assert.ok((options.idempotencyKey as string).length > 0);
assert.equal(screen.queryByRole("button", { name: "boundary" }), null); expect(screen.queryByRole("button", { name: "boundary" })).not.toBeInTheDocument();
// `findByText` above already settled on the post-delete render -- the // `findByText` above already settled on the post-delete render -- the
// `queueMicrotask`-scheduled focus call has necessarily run by then, since // `queueMicrotask`-scheduled focus call has necessarily run by then, since
@@ -224,8 +224,16 @@ test("removes the asset and restores focus to the page heading, not the detached
// (its polling uses `setTimeout`/`MutationObserver`), and microtasks always // (its polling uses `setTimeout`/`MutationObserver`), and microtasks always
// drain before the next macrotask runs. So this asserts directly rather // drain before the next macrotask runs. So this asserts directly rather
// than polling. // than polling.
//
// `toHaveFocus`, never `assert.equal(document.activeElement, heading)`:
// node:assert builds an AssertionError by running `util.inspect` over both
// operands at `depth: 1000`, and a React-rendered element carries
// `__reactFiber$*` own properties whose graph re-expands per traversal
// path. Inspecting one costs gigabytes, so the regression this test guards
// used to kill the worker instead of reporting itself. jest-dom prints DOM
// nodes through pretty-format's DOM plugin, which never touches the fiber.
const heading = screen.getByRole("heading", { name: "Asset", level: 1 }); const heading = screen.getByRole("heading", { name: "Asset", level: 1 });
assert.equal(document.activeElement, heading); expect(heading).toHaveFocus();
}); });
// --- Alignment follow-up, item 1: the management screen gets search and paging --- // --- Alignment follow-up, item 1: the management screen gets search and paging ---
@@ -280,7 +288,7 @@ test("searches assets with the typed query and announces the new result count",
await user.click(screen.getByRole("button", { name: "검색" })); await user.click(screen.getByRole("button", { name: "검색" }));
assert.ok(await screen.findByRole("button", { name: "older-diagram" })); assert.ok(await screen.findByRole("button", { name: "older-diagram" }));
assert.equal(screen.queryByRole("button", { name: "newer-diagram" }), null); expect(screen.queryByRole("button", { name: "newer-diagram" })).not.toBeInTheDocument();
assert.equal(calls.at(-1)?.q, "older"); assert.equal(calls.at(-1)?.q, "older");
// The result count lives in a `role="status"` region so a screen reader is // The result count lives in a `role="status"` region so a screen reader is
// told the list changed -- a silently re-rendered list is the failure mode // told the list changed -- a silently re-rendered list is the failure mode
@@ -324,7 +332,7 @@ test("loads the next page with the server cursor and appends it to the list", as
assert.equal(calls.at(-1)?.cursor, "cursor-1"); assert.equal(calls.at(-1)?.cursor, "cursor-1");
// Exhausted paging removes the control rather than leaving a button that // Exhausted paging removes the control rather than leaving a button that
// does nothing. // does nothing.
assert.equal(screen.queryByRole("button", { name: "더 보기" }), null); expect(screen.queryByRole("button", { name: "더 보기" })).not.toBeInTheDocument();
}); });
test("더 보기 moves focus to the first newly loaded asset instead of stranding it on the removed control", async () => { test("더 보기 moves focus to the first newly loaded asset instead of stranding it on the removed control", async () => {
@@ -342,21 +350,14 @@ test("더 보기 moves focus to the first newly loaded asset instead of strandin
await user.click(screen.getByRole("button", { name: "더 보기" })); await user.click(screen.getByRole("button", { name: "더 보기" }));
const appended = await screen.findByRole("button", { name: "focus-page-two" }); const appended = await screen.findByRole("button", { name: "focus-page-two" });
// Compared as a boolean, not as two nodes: `assert.equal(node, node)` builds expect(appended).toHaveFocus();
// its failure message by inspecting both jsdom elements, and that traversal
// is heavy enough to take the worker down instead of reporting the failure.
assert.equal(
document.activeElement === appended,
true,
`focus was on ${document.activeElement?.textContent ?? "nothing"}`,
);
}); });
test("offers no 더 보기 control when the server reports no next cursor", async () => { test("offers no 더 보기 control when the server reports no next cursor", async () => {
render(<AssetLibrary gateway={gatewayOf({ asset: ASSET, usages: [], hasPublicationHistory: false })} />); render(<AssetLibrary gateway={gatewayOf({ asset: ASSET, usages: [], hasPublicationHistory: false })} />);
await screen.findByRole("button", { name: "boundary" }); await screen.findByRole("button", { name: "boundary" });
assert.equal(screen.queryByRole("button", { name: "더 보기" }), null); expect(screen.queryByRole("button", { name: "더 보기" })).not.toBeInTheDocument();
}); });
test("a new search restarts paging from the first page instead of carrying the old cursor", async () => { test("a new search restarts paging from the first page instead of carrying the old cursor", async () => {
@@ -380,8 +381,8 @@ test("a new search restarts paging from the first page instead of carrying the o
await user.click(screen.getByRole("button", { name: "검색" })); await user.click(screen.getByRole("button", { name: "검색" }));
assert.ok(await screen.findByRole("button", { name: "reset-found" })); assert.ok(await screen.findByRole("button", { name: "reset-found" }));
assert.equal(screen.queryByRole("button", { name: "reset-page-one" }), null); expect(screen.queryByRole("button", { name: "reset-page-one" })).not.toBeInTheDocument();
assert.equal(screen.queryByRole("button", { name: "reset-page-two" }), null); expect(screen.queryByRole("button", { name: "reset-page-two" })).not.toBeInTheDocument();
assert.equal(calls.at(-1)?.cursor, undefined); assert.equal(calls.at(-1)?.cursor, undefined);
}); });
@@ -438,7 +439,7 @@ test("a slow earlier search never overwrites the newer search's results", async
pending[1]!.settle({ items: [slow], nextCursor: null }); pending[1]!.settle({ items: [slow], nextCursor: null });
}); });
assert.equal(screen.queryByRole("button", { name: "race-slow" }), null); expect(screen.queryByRole("button", { name: "race-slow" })).not.toBeInTheDocument();
assert.ok(screen.getByRole("button", { name: "race-fast" })); assert.ok(screen.getByRole("button", { name: "race-fast" }));
}); });
@@ -454,5 +455,5 @@ test("a search that matches nothing says so instead of claiming no asset was eve
await user.click(screen.getByRole("button", { name: "검색" })); await user.click(screen.getByRole("button", { name: "검색" }));
assert.ok(await screen.findByText("조건에 맞는 Asset이 없습니다")); assert.ok(await screen.findByText("조건에 맞는 Asset이 없습니다"));
assert.equal(screen.queryByText("등록된 Asset이 없습니다"), null); expect(screen.queryByText("등록된 Asset이 없습니다")).not.toBeInTheDocument();
}); });
tests/features/tech-log/asset-picker.test.tsx
+15 -10
View File
@@ -1,7 +1,7 @@
// @vitest-environment jsdom // @vitest-environment jsdom
import assert from "node:assert/strict"; import assert from "node:assert/strict";
import { afterAll, beforeAll, test } from "vitest"; import { afterAll, beforeAll, expect, test } from "vitest";
import { act, fireEvent, render, screen, waitFor, within } from "@testing-library/react"; import { act, fireEvent, render, screen, waitFor, within } from "@testing-library/react";
import userEvent from "@testing-library/user-event"; import userEvent from "@testing-library/user-event";
import { MemoryRouter } from "react-router-dom"; import { MemoryRouter } from "react-router-dom";
@@ -143,7 +143,7 @@ test("does not offer a QUARANTINED asset for insertion", async () => {
render(<AssetPicker gateway={gatewayOf([READY, QUARANTINED])} onInsert={() => {}} />); render(<AssetPicker gateway={gatewayOf([READY, QUARANTINED])} onInsert={() => {}} />);
await screen.findByRole("button", { name: /fetch-strategy-boundary/ }); await screen.findByRole("button", { name: /fetch-strategy-boundary/ });
assert.equal(screen.queryByRole("button", { name: /unsafe/ }), null); expect(screen.queryByRole("button", { name: /unsafe/ })).not.toBeInTheDocument();
}); });
test("reports the loaded Asset list once listAssets resolves", async () => { test("reports the loaded Asset list once listAssets resolves", async () => {
@@ -398,14 +398,19 @@ test("focuses the file input on open, traps Tab inside the dialog, and calls onC
const altInput = screen.getByLabelText("대체 텍스트"); const altInput = screen.getByLabelText("대체 텍스트");
const uploadButton = screen.getByRole("button", { name: "업로드" }); const uploadButton = screen.getByRole("button", { name: "업로드" });
const closeButton = screen.getByRole("button", { name: "닫기" }); const closeButton = screen.getByRole("button", { name: "닫기" });
assert.equal(document.activeElement, input); // `toHaveFocus`, never `assert.equal(document.activeElement, input)`:
// node:assert inspects both operands at `depth: 1000` to build its failure
// message, and a React-rendered element's `__reactFiber$*` graph re-expands
// per traversal path, so inspecting one exhausts the heap and kills the
// worker instead of reporting the regression.
expect(input).toHaveFocus();
// Final fix wave, item 2: the trap now has to hold across the two metadata // Final fix wave, item 2: the trap now has to hold across the two metadata
// controls the dialog gained, and still wrap from the last back to the first. // controls the dialog gained, and still wrap from the last back to the first.
input.focus(); input.focus();
for (const expected of [decorativeBox, altInput, closeButton, uploadButton, input]) { for (const expected of [decorativeBox, altInput, closeButton, uploadButton, input]) {
await user.tab(); await user.tab();
assert.equal(document.activeElement, expected); expect(expected).toHaveFocus();
} }
await user.click(closeButton); await user.click(closeButton);
@@ -457,7 +462,7 @@ test("inserts the directive at the saved cursor position and the live preview re
await user.click(screen.getByRole("tab", { name: "즉시 미리보기" })); await user.click(screen.getByRole("tab", { name: "즉시 미리보기" }));
const panel = screen.getByRole("tabpanel", { name: "즉시 미리보기" }); const panel = screen.getByRole("tabpanel", { name: "즉시 미리보기" });
assert.equal(within(panel).queryByRole("alert"), null); expect(within(panel).queryByRole("alert")).not.toBeInTheDocument();
// `zoom: true` (DIAGRAM kind) renders the figure's image twice -- once as // `zoom: true` (DIAGRAM kind) renders the figure's image twice -- once as
// the zoom trigger, once inside the (closed) zoom dialog -- both share the // the zoom trigger, once inside the (closed) zoom dialog -- both share the
// same alt text, so assert on the first (the visible trigger figure). // same alt text, so assert on the first (the visible trigger figure).
@@ -1299,7 +1304,7 @@ test("Instant Preview renders the same asset the gate and the descriptor picked
[newer, older], [newer, older],
); );
assert.equal(screen.queryByRole("alert"), null); expect(screen.queryByRole("alert")).not.toBeInTheDocument();
assert.equal( assert.equal(
screen.getByAltText("중복 키 그림").getAttribute("src"), screen.getByAltText("중복 키 그림").getAttribute("src"),
"/media/dup-pixels-newer.svg", "/media/dup-pixels-newer.svg",
@@ -1629,7 +1634,7 @@ test("the Picker shows a first page before anything is typed, then narrows to th
await user.click(screen.getByRole("button", { name: "검색" })); await user.click(screen.getByRole("button", { name: "검색" }));
await waitFor(() => await waitFor(() =>
assert.equal(screen.queryByRole("button", { name: /inserted-diagram/ }), null), expect(screen.queryByRole("button", { name: /inserted-diagram/ })).not.toBeInTheDocument(),
); );
assert.ok(screen.getByRole("button", { name: /other-diagram/ })); assert.ok(screen.getByRole("button", { name: /other-diagram/ }));
assert.equal(calls.at(-1)?.q, "other"); assert.equal(calls.at(-1)?.q, "other");
@@ -1680,7 +1685,7 @@ test("a QUARANTINED asset the server wrongly returns for a query is still not of
await waitFor(() => await waitFor(() =>
assert.ok(screen.getByRole("button", { name: /inserted-diagram/ })), assert.ok(screen.getByRole("button", { name: /inserted-diagram/ })),
); );
assert.equal(screen.queryByRole("button", { name: /unsafe-diagram/ }), null); expect(screen.queryByRole("button", { name: /unsafe-diagram/ })).not.toBeInTheDocument();
}); });
test("the Picker reports search results too, so the catalog grows with every query", async () => { test("the Picker reports search results too, so the catalog grows with every query", async () => {
@@ -1753,7 +1758,7 @@ test("a slow earlier Picker search never overwrites the newer query's results",
pending[1]!.settle({ items: [PICKER_A], nextCursor: null }); pending[1]!.settle({ items: [PICKER_A], nextCursor: null });
}); });
assert.equal(screen.queryByRole("button", { name: /inserted-diagram/ }), null); expect(screen.queryByRole("button", { name: /inserted-diagram/ })).not.toBeInTheDocument();
assert.ok(screen.getByRole("button", { name: /other-diagram/ })); assert.ok(screen.getByRole("button", { name: /other-diagram/ }));
}); });
@@ -1792,7 +1797,7 @@ test("a Picker search never drops an already-inserted asset out of Instant Previ
await user.type(screen.getByLabelText("Asset 검색"), "other"); await user.type(screen.getByLabelText("Asset 검색"), "other");
await user.click(screen.getByRole("button", { name: "검색" })); await user.click(screen.getByRole("button", { name: "검색" }));
await waitFor(() => await waitFor(() =>
assert.equal(screen.queryByRole("button", { name: /inserted-diagram/ }), null), expect(screen.queryByRole("button", { name: /inserted-diagram/ })).not.toBeInTheDocument(),
); );
await user.click(screen.getByRole("tab", { name: "즉시 미리보기" })); await user.click(screen.getByRole("tab", { name: "즉시 미리보기" }));
vitest.config.ts
+10
View File
@@ -8,6 +8,16 @@ export default defineConfig({
clearMocks: true, clearMocks: true,
mockReset: true, mockReset: true,
testTimeout: 10_000, testTimeout: 10_000,
// A runaway serialization inside a worker (the classic case: an assertion
// library inspecting a React-rendered DOM node, whose `__reactFiber$*`
// graph re-expands per traversal path) allocates until the machine's OOM
// killer takes the whole run down -- 29.5GB and ~40s here, reported as a
// bare "worker exited" with no failing test named. Capping the worker's
// old-space turns that into a `Reached heap limit` abort in ~3s, next to
// the file that caused it. The ceiling is chosen well above real demand:
// the heaviest suite (`tests/unit`, 126 files) peaks near 1.3GB RSS, of
// which old-space is only a fraction.
execArgv: ["--max-old-space-size=2048"],
exclude: [ exclude: [
...configDefaults.exclude, ...configDefaults.exclude,
".tmp/**", ".tmp/**",