abhigyanpatwari/GitNexus · error

Duplicate analysis feature descriptor: ${descriptor.id}

Error message

Duplicate analysis feature descriptor: ${descriptor.id}

What it means

`resolveAnalysisFeatureVersions` encountered two `AnalysisFeatureDescriptor` entries with the same `id`. The feature registry requires unique ids because the id is the key stamped into index metadata and compared during rebuild detection. Duplicate ids would make rollback/mismatch detection ambiguous.

Source

Thrown at gitnexus/src/core/analysis-features.ts:38

/** Resolve the exact feature set this build promises for the supplied files. */
export function resolveAnalysisFeatureVersions(
  descriptors: readonly AnalysisFeatureDescriptor[],
  filePaths: readonly string[],
): Record<string, number> {
  const resolved = new Map<string, number>();
  const seenIds = new Set<string>();
  for (const descriptor of descriptors) {
    if (descriptor.id.trim().length === 0) {
      throw new Error('Analysis feature descriptor id must not be empty');
    }
    if (!Number.isSafeInteger(descriptor.version) || descriptor.version < 1) {
      throw new Error(
        `Analysis feature "${descriptor.id}" has invalid version ${descriptor.version}`,
      );
    }
    if (seenIds.has(descriptor.id)) {
      throw new Error(`Duplicate analysis feature descriptor: ${descriptor.id}`);
    }
    seenIds.add(descriptor.id);
    if (!descriptor.appliesTo(filePaths)) continue;
    resolved.set(descriptor.id, descriptor.version);
  }

  return Object.fromEntries([...resolved].sort(([left], [right]) => left.localeCompare(right)));
}

/**
 * Compare an untrusted metadata value with the exact capabilities produced by
 * this build. Extra keys also mismatch: a rollback must rebuild instead of
 * certifying graph semantics emitted only by a newer binary.
 */
export function findAnalysisFeatureMismatches(
  actual: unknown,
  expected: AnalysisFeatureVersions,
): readonly string[] {

View on GitHub (pinned to d540b00184)

Solutions

1. Remove the duplicate registration so each id appears exactly once.
2. If both features are legitimate, give each a distinct namespaced id.
3. Add a unit test asserting the descriptor list has unique ids.

Example fix

// before
[{ id: 'graph.x', version: 1, appliesTo: () => true },
 { id: 'graph.x', version: 2, appliesTo: () => true }]
// after
[{ id: 'graph.x', version: 2, appliesTo: () => true },
 { id: 'graph.y', version: 1, appliesTo: () => true }]

const ids = new Set();
for (const d of descriptors) {
  if (ids.has(d.id)) throw new Error('Duplicate analysis feature: ' + d.id);
  ids.add(d.id);
}

When it happens

Trigger: Registering the same feature descriptor object twice, or two new descriptors that happen to share an id string (e.g. both start with 'graph.').

Common situations: A refactor that split a descriptor module but accidentally kept both the old and new registration; copy-paste of a descriptor without changing the id; merging two feature branches that each added a colliding id.

Related errors

• Analysis feature descriptor id must not be empty
• Analysis feature "${descriptor.id}" has invalid version ${de
• [understand-quickly] expected id of the form "owner/repo", g
• Unsupported provider: ${(config as any).provider}
• Invalid backend URL: must be a well-formed http:// or https:

AI-assisted analysis of abhigyanpatwari/GitNexus@d540b00184 (2026-08-12). Data as JSON: /api/errors/b29781c2410a7c71. Report an issue: GitHub.