TryGhost/Ghost · critical · Error

[e2e fixture] Failed to initialize per-file Ghost instance.

Error message

[e2e fixture] Failed to initialize per-file Ghost instance.

What it means

In per-file isolation, the fixture caches a Ghost instance (cachedPerFileInstance) and recycles it across files. If after the recycle logic activePerFileInstance is still falsy, setup never produced an instance — perFileSetup returned null/undefined or threw silently upstream and the cache stayed empty. The fixture cannot hand a null instance to tests.

Source

Thrown at e2e/helpers/playwright/fixture.ts:399

                config: mergedConfig,
                stripe
            });
            cachedPerFileInstance = {
                suiteKey,
                environmentSignature,
                instance: nextPerFileInstance
            };
            cachedPerFileGhostAccountOwner = null;
            cachedPerFileAuthenticatedSession = null;

            if (previousPerFileInstance) {
                await environmentManager.perTestTeardown(previousPerFileInstance);
            }
        }

        const activePerFileInstance = cachedPerFileInstance;
        if (!activePerFileInstance) {
            throw new Error('[e2e fixture] Failed to initialize per-file Ghost instance.');
        }

        const holder = {...activePerFileInstance.instance};
        const cycle = async () => {
            const previousInstance = cachedPerFileInstance?.instance;
            const nextInstance = await environmentManager.perTestSetup({
                config: mergedConfig,
                stripe
            });

            if (previousInstance) {
                await environmentManager.perTestTeardown(previousInstance);
            }

            cachedPerFileInstance = {
                suiteKey,
                environmentSignature,
                instance: nextInstance

View on GitHub (pinned to 47d8b0e2ad)

Solutions

Inspect why perFileSetup returned falsy — add logging around environmentManager.perFileSetup to see its return value and any swallowed error.
Ensure perFileSetup throws on real failure rather than returning null, so the root cause surfaces.
Confirm isolation mode (per-file) is supported by the active environment manager.
Check the stripe/config branch didn't skip instance creation for this file.

Example fix

// before
const activePerFileInstance = cachedPerFileInstance;
if (!activePerFileInstance) {
    throw new Error('[e2e fixture] Failed to initialize per-file Ghost instance.');
}

// after
const activePerFileInstance = cachedPerFileInstance;
if (!activePerFileInstance) {
    throw new Error(`[e2e fixture] per-file Ghost instance is null after setup (isolation=${resolvedIsolation}, stripe=${stripe}); see preceding perFileSetup logs`);
}

Defensive patterns

Strategy: validation

Validate before calling

const inst = await environmentManager.perFileSetup({config: mergedConfig, stripe});
if (!inst?.instance) {
    throw new Error('perFileSetup returned no instance — setup failed');
}

Type guard

function isPerFileInstance(x: unknown): x is {instance: GhostInstance} {
    return typeof x === 'object' && x !== null && 'instance' in x && x.instance != null;
}

Try / catch

try {
    cachedPerFileInstance = await environmentManager.perFileSetup({config: mergedConfig, stripe});
} catch (e) {
    throw new Error('[e2e fixture] per-file setup threw', {cause: e});
}
if (!cachedPerFileInstance?.instance) {
    throw new Error('[e2e fixture] per-file setup returned no instance');
}

Prevention

Make perFileSetup throw on failure instead of returning null so the root cause surfaces.
Log perFileSetup return values during fixture bring-up to detect partial failures.
Confirm the environment manager supports the resolved isolation mode.

When it happens

Trigger: environmentManager.perFileSetup returned a falsy instance (no error thrown). An earlier branch skipped instance creation. A previous perTestTeardown nulled the cache and the subsequent setup didn't repopulate. Misconfigured isolation mode resolved to per-file but the manager can't serve it.

Common situations: Environment manager implementation gap for per-file mode; setup partially failed and returned null instead of throwing; fixture conditionals (e.g. stripe flag) routed away from instance creation.

Related errors

AI-assisted analysis of TryGhost/Ghost@47d8b0e2ad (2026-08-13). Data as JSON: /api/errors/f94bf48f4f8e95a1. Report an issue: GitHub.