Propagate fatal error from Link query in FDS#722
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stefanvanburen merged 1 commit intomainfrom Apr 29, 2026
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`FDS.Execute` was not checking `linkResult[0].Fatal` before iterating over IR files. When `Link.Execute` fails fatally (e.g. due to a file-open error like `DuplicateProtoPathError`), its result value is nil, so FDS silently produced an empty `FileDescriptorSet` with no fatal error instead of propagating the underlying error to callers. Add the same guard used elsewhere in this package — identical to the check in `IR.Execute` after its `AST` sub-query (`ir.go:62-64`), and to the `fdpResults` check already present later in `FDS.Execute` itself.
stefanvanburen
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Apr 28, 2026
When a proto file is contained in multiple modules (DuplicateProtoPathError), the new experimental compiler was silently swallowing the typed error: FDS did not check the fatal error from its Link sub-query, producing an empty FileDescriptorSet instead of propagating the error upward. This meant callers of compileImage could not inspect it via errors.As, and the downstream "nil FileDescriptor" panic was unhelpful. The fix is in protocompile (bufbuild/protocompile#722): FDS.Execute now checks linkResult[0].Fatal before iterating over IR files, propagating the Link fatal as its own. With this, results[0].Fatal in compileImage is DuplicateProtoPathError, which is returned directly so callers retain its type information and the existing "Failure: " / exit code 1 behavior is preserved.
doriable
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Apr 29, 2026
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FDS.Executewas not checkinglinkResult[0].Fatalbefore iterating over IR files. WhenLink.Executefails fatally (e.g. due to a file-open error likeDuplicateProtoPathError), its result value is nil, so FDS silently produced an emptyFileDescriptorSetwith no fatal error instead of propagating the underlying error to callers.Add the same guard used elsewhere in this package — identical to the check in
IR.Executeafter itsASTsub-query (ir.go:62-64), and to thefdpResultscheck already present later inFDS.Executeitself.