fix(protoc): honor --fatal_warnings in encode/decode mode#28033
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yashanil98 wants to merge 1 commit into
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fix(protoc): honor --fatal_warnings in encode/decode mode#28033yashanil98 wants to merge 1 commit into
yashanil98 wants to merge 1 commit into
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protoc emits a warning when an input message passed to --encode or --decode is missing required fields, but that warning was printed directly to stderr in EncodeOrDecode and never affected the exit code, so protoc returned 0 even with --fatal_warnings set. Make EncodeOrDecode return a non-zero exit when --fatal_warnings is set and the message is missing required fields, after the output has been written so the behavior matches the compile path. Output and the warning are still produced when --fatal_warnings is not set. Fixes protocolbuffers#10486
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Fixes #10486.
When an input message passed to
protoc --encodeor--decodeis missing required fields, protoc printswarning: Input message is missing required fields: .... That warning was written straight to stderr inEncodeOrDecodeand never influenced the exit code, so protoc returned 0 even with--fatal_warningsset, defeating its-Werror-like purpose.This makes
EncodeOrDecodereturn a non-zero exit when--fatal_warningsis set and the message is missing required fields. The check happens after the output is written, matching the compile path (which also produces its output before failing). When--fatal_warningsis not set, behavior is unchanged: the output and the warning are still produced and the exit code stays 0.A maintainer confirmed this is a valid bug and invited a PR on the issue.
Test: added
EncodeDecodeTest.PartialWithFatalWarningsasserting a non-zero exit (and that the warning is still emitted) when encoding a message with missing required fields under--fatal_warnings../build/tests --gtest_filter='EncodeDecodeTest.'
Result: 18 tests pass, including the new one.