merge(third_party/git): Merge squashed git subtree at v2.23.0 r/373

Merge commit '1b593e1ea4d2af0f6444d9a7788d5d99abd6fde5' as 'third_party/git'

1 files changed, 67 insertions, 0 deletions

diff --git a/third_party/git/Documentation/config/fsck.txt b/third_party/git/Documentation/config/fsck.txt
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+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.<msg-id>.*`. 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 they must all 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.
+
+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 is 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 they must all 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.