fsck

fsck.<msg-id>
During fsck git may find issues with legacy data which wouldn’t be generated by current versions of git, and which wouldn’t be sent over the wire if transfer.fsckObjects was set. This feature is intended to support working with legacy repositories containing such data.

Setting fsck.<msg-id> will be picked up by linkgit:git-fsck[1], but to accept pushes of such data set receive.fsck.<msg-id> instead, or to clone or fetch it set fetch.fsck.<msg-id>.

The rest of the documentation discusses fsck.* for brevity, but the same applies for the corresponding receive.fsck.* and fetch.fsck.*. variables.

Unlike variables like color.ui and core.editor, the receive.fsck.<msg-id> and fetch.fsck.<msg-id> variables will not fall back on the fsck.<msg-id> configuration if they aren’t set. To uniformly configure the same fsck settings in different circumstances, all three of them must be set to the same values.

When fsck.<msg-id> is set, errors can be switched to warnings and vice versa by configuring the fsck.<msg-id> setting where the <msg-id> is the fsck message ID and the value is one of error, warn or ignore. For convenience, fsck prefixes the error/warning with the message ID, e.g. "missingEmail: invalid author/committer line - missing email" means that setting fsck.missingEmail = ignore will hide that issue.

In general, it is better to enumerate existing objects with problems with fsck.skipList, instead of listing the kind of breakages these problematic objects share to be ignored, as doing the latter will allow new instances of the same breakages go unnoticed.

Setting an unknown fsck.<msg-id> value will cause fsck to die, but doing the same for receive.fsck.<msg-id> and fetch.fsck.<msg-id> will only cause git to warn.

See the Fsck Messages section of linkgit:git-fsck[1] for supported values of <msg-id>.

fsck.skipList
The path to a list of object names (i.e. one unabbreviated SHA-1 per line) that are known to be broken in a non-fatal way and should be ignored. On versions of Git 2.20 and later, comments (’#’), empty lines, and any leading and trailing whitespace are ignored. Everything but a SHA-1 per line will error out on older versions.

This feature is useful when an established project should be accepted despite early commits containing errors that can be safely ignored, such as invalid committer email addresses. Note: corrupt objects cannot be skipped with this setting.

Like fsck.<msg-id> this variable has corresponding receive.fsck.skipList and fetch.fsck.skipList variants.

Unlike variables like color.ui and core.editor the receive.fsck.skipList and fetch.fsck.skipList variables will not fall back on the fsck.skipList configuration if they aren’t set. To uniformly configure the same fsck settings in different circumstances, all three of them must be set to the same values.

Older versions of Git (before 2.20) documented that the object names list should be sorted. This was never a requirement; the object names could appear in any order, but when reading the list we tracked whether the list was sorted for the purposes of an internal binary search implementation, which could save itself some work with an already sorted list. Unless you had a humongous list there was no reason to go out of your way to pre-sort the list. After Git version 2.20 a hash implementation is used instead, so there’s now no reason to pre-sort the list.