UNCOMMITTED_INPUT_OVERWRITTEN
A stateful property binding (value/checked/…) re-wrote an unchanged value over an edit the user never committed to the signal (dev; client).
What you saw
- Kind:
render - Severity:
warn(code that works but is structurally wrong or expensive)
The console report opens with [UNCOMMITTED_INPUT_OVERWRITTEN] and the message, then an in line naming the owners that enclose the subject, root first, and an at line with the source location when the code was compiled with one.
In a captured artifact the same finding is an event with code: "UNCOMMITTED_INPUT_OVERWRITTEN", ownerPath, and loc.
Diagnostics explains each line.
Why it fires
A stateful property binding (value/checked on an input, value on a textarea, selected on an option, muted on media) re-wrote the value it wrote last time over an edit the user made and never committed to the bound signal — the typed text (or toggled box) is lost.
The binding shares its template's grouped effect, so any other dynamic attribute in the same template changing re-runs it; so does a spread re-run or an equals: false source firing an equal value.
Typical cause: value={props.name} onChange={commit} with no draft signal.
Once per element and property; the write still happens.
The server runtime reports on the same channel, with the same in <App> › <Page> line.
Two groups.
Findings (SSR_RENDER_ERROR_CONTAINED, SSR_SUBTREE_ABANDONED, SSR_STREAM_ABANDONED, LATE_HEADER_WRITE, DYNAMIC_ASYNC_COMPONENT, SERVER_ERROR_SANITIZED, FRAME_MARKER_CORRUPTED) are facts about a render that exist in observe builds too — an APM sees them in production; in dev they print.
Checks (the rest, SSR_BOUNDARY_WATERFALL and SSR_CLIENT_CONTENT_MASKED included) are dev-only guidance.
A captured artifact from a server render carries both.
How to fix it
Fix: write the signal on every edit (onInput={e => setDraft(e.currentTarget.value)}, commit the draft separately), use defaultValue/defaultChecked for an uncontrolled element, or reject an edit by writing the accepted value back in the handler (e.currentTarget.value = next) instead of re-asserting an equal value through the signal.
In tests
captureArtifact from @solidjs/diagnostics runs a scenario with the diagnostics channel open and returns the events it saw.
expectNoDiagnostics(artifact) fails while UNCOMMITTED_INPUT_OVERWRITTEN is among them, with the events as evidence; after the fix, the code is gone from artifact.diagnostics.
Check for regressions in tests shows the loop and the Vitest matcher form.
Learn more
- Diagnostics: every code, with its kind, severity, and trigger.
- Debugging reactivity: how to read a report and what each group of codes points at.