Sample
Manage IO stream lifecycles, EOF positions, and monolithic buffer allocations in JSON.dump and JSON.load
sha256:ab7ff319b674d45bcbd2a67d43b257f7a387c8b14d38d85018607794429d5106
PUBLISHED
L3_CONTRACT_PASS
MIT-0
Case
- Goal
- Manage IO stream lifecycles, EOF positions, and monolithic buffer allocations in JSON.dump and JSON.load HOW
- Packages
- json 2.9.1
- Environment
- ruby
- Created
- 2026-08-17T02:43:58Z
Commonly assumed
Passing an IO object to JSON.dump or JSON.load automatically closes or rewinds the stream upon completion, returns the serialized JSON string from dump, and streams writes and reads incrementally without buffering full documents in memory.
The sample's author recorded this as what a developer or model would expect here. The contract below is what actually ran.
Contract
- assert JSON.dump and JSON.load leave passed IO streams open at EOF rather than closing or rewinding them, dump returns the IO object instead of the JSON string, and both operations buffer the entire payload in memory in a single monolithic read or write rather than streaming chunks
- assert JSON.dump and JSON.load leave the stream open and unrewound at EOF even when an error occurs during parsing or generation
- assert JSON.dump returns the IO instance when given a stream but returns a JSON String when the second argument is an integer limit
- assert JSON.parse rejects IO streams with TypeError, requiring explicit conversion to string or use of JSON.load with its unclosed stream caveat
- assert JSON::Parser retains its source string and re-parses from the retained string on subsequent parse calls rather than consuming or discarding it
- assert JSON.dump buffers the complete document before calling IO#write once, so a slow or aborted dump writes zero bytes rather than partial fragments
Files
- Gemfile
- Gemfile.lock
- NOTES.md
- csx.json
- src/resource_ops.rb
- test/contract.rb
Download the verified artifact (tar.gz) — the exact bytes the contract ran against
Origin Seeder
Verification receipts
- ruby 3 · CONTAINER_RUN · compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS · rubygems@1 · 2026-08-17 · ed25519:d91480838ac982c9