fix: retain Tempfile reference to prevent cloud-init ISO GC race#191
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The Tempfile object was immediately discarded after calling .path, making it eligible for garbage collection. When GC finalized the object, the underlying ISO file was deleted before File.size could read it, causing flaky ENOENT failures in CI.
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ekohl
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May 30, 2026
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Thanks for the explanation. I would have never suspected the GC to be so aggressive in cleaning it up. I suspected it was more due to leaking file descriptors.
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Summary
Splits an unrelated fix out of #190 at a maintainer's request.
generate_config_isocalledTempfile.new(['init', '.iso']).pathand immediately discarded theTempfileobject. Once GC finalized it, the underlying ISO file was unlinked before downstream code could read it, causing flakyENOENTfailures.This retains the
Tempfilereference for the lifetime of the block and explicitly cleans it up in anensure.Changes
Tempfileobject iniso_tempfile; deriveisofilefrom.path.ensure iso_tempfile&.close!to unlink deterministically instead of relying on GC timing.Test plan