mcp: add race and 1.25 tests, fix a bug in streamable transport #239
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This CL makes the following changes to our Github workflows, motivated by modelcontextprotocol#227: - Add -race tests. - Add go1.25rc2 to the build matrix. - Check out code before setting up Go, so that the setup step can use dependency caching.
As reported in modelcontextprotocol#227, there was a race where streams could be terminated before the final reply was written. Fix this by checking the number of outstanding requests in the same critical section that acquires outgoing messages to write. Fixes modelcontextprotocol#227
findleyr
changed the title
samthanawalla
approved these changes
Aug 5, 2025
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This PR contains two commits. The first adds race tests to our build matrix, inspired by #227. While the race in #227 is a logical race, not a data race, it is still the case that the slower timing of race tests made it more reproducible with the race detector enabled.
The second commit fixes the bug in the streamable server transport, by checking outstanding requests in the same critical section as acquiring data to write.