App.render rejects null and undefined options valuesConfig & EnvironmentEasyPreparing

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Incident Dossier

App.render rejects null and undefined options values

A caller invokes `app.render(viewName, options, callback)` and expects the callback to deliver the rendered template string even when `options` is `null` or `undefined`. The callback does not deliver the expected rendered output for those cases, while rendering with a normal options object continues to succeed.

Initial failing signalNull or undefined options prevents rendered output deliveryExpected behavior: `app.render(view, null, cb)` and `app.render(view, undefined, cb)` deliver rendered strings (e.g., `'<p>tobi</p>'`) via the callback. Rendering with a normal options object still works. · actual behavior: `app.render(view, null, cb)` and `app.render(view, undefined, cb)` fail to deliver the expected rendered template string via the callback. Rendering with a normal options object still works.

Progress

1Reproduce the bugRun checks

2Edit the fixOpen

3Pass checksOpen

4Submit fixOpen

Reproduction Steps

Install dependencies in the repo snapshot.
Run the visible regression test command.
Trace from the failing test into the changed runtime source files.

Focus Mode

Start

test/app.render.js

Likely area

test/app.render.js

Repo scale

213 files
Real expressjs/express repo snapshot

Challenge Coach

Hints reveal broad direction first, then narrow toward the suspect path without showing hidden tests or exact solution code.

TopicConfig & Environment

DifficultyEasy

Est. time10 min

Workspacepreparing

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Evidence Map

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Initial failing signalBaseline

Null or undefined options prevents rendered output delivery

Expected behavior`app.render(view, null, cb)` and `app.render(view, undefined, cb)` deliver rendered strings (e.g., `'<p>tobi</p>'`) via the callback. Rendering with a normal options object still works.

Actual behavior`app.render(view, null, cb)` and `app.render(view, undefined, cb)` fail to deliver the expected rendered template string via the callback. Rendering with a normal options object still works.

Related checkInstall dependencies

Check suite

2 visible

Install dependenciesPrepares this workspace.

not run

Visible OSS regression testRuns the visible regression check.

not run

Hidden validationRuns only on submit; details stay server-side.

locked

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