lib: optimize file handle usage when calling into same_file during checkout
#7742
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landaire
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same_filesame_file during checkout
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landaire
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landaire
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checkout See jj-vcs#7695 for motivation/background One of the hottest paths in `jj` during checkout is `can_create_file` and `create_parent_dirs`. Both of these functions check to ensure that there aren't attempts to write to special directories (`reject_reserved_existing`) which is a fairly expensive check. This change reduces file open/close syscalls by reusing file handles when possible.
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See #7695 for motivation/background
One of the hottest paths in
jjduring checkout iscan_create_fileandcreate_parent_dirs. Both of these functions check to ensure that there aren't attempts to write to special directories (reject_reserved_existing) which is a fairly expensive check.This change reduces file open/close syscalls by reusing file handles when possible.
Checklist
If applicable:
CHANGELOG.mdREADME.md,docs/,demos/)cli/src/config-schema.json)