When we get 40 hex digits, we immediately assume it's an SHA-1. This
is the right thing to do because we have no way else to specify an
object. If there is a ref with the same object name, it will be
ignored. Warn the user about this case because the ref with full
object name is likely a mistake, for example
git checkout -b $empty_var $(git rev-parse something)
advice.object_name_warning is not documented because frankly people
should not be aware about it until they encounter this situation.
While at there, warn about ambiguation with abbreviated SHA-1 too.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The test creates 16 objects that share the same prefix, and two other
objects that do not. Tweak the test so that the other two share the
same prefix that is different from the one that is shared by the 16.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Some implementations of sed (e.g. MacOS X) have whitespaces in the
output of "wc -l" that reads from the standard input. Ignore these
whitespaces by not quoting the command substitution to be compared
with the constant "16".
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The new option allows you to feed an ambiguous prefix and enumerate
all the objects that share it as a prefix of their object names.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This is not strictly correct, in that resetting selected index
entries from corresponding paths out of a given tree without moving
HEAD is a valid operation, and in such case a tree-ish would suffice.
But the existing code already requires a committish in the codepath,
so let's be consistent with it for now.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The "index" line read from the patch to reconstruct a partial
preimage tree records the object names of blob objects.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This teaches the revision parser that in "$name:$path" (used for a
blob object name), "$name" must be a tree-ish.
There are many more places where we know what types of objects are
called for. This patch adds support for "commit", "treeish", "tree",
and "blob", which could be used in the following contexts:
- "git apply --build-fake-ancestor" reads the "index" lines from
the patch; they must name blob objects (not even "blob-ish");
- "git commit-tree" reads a tree object name (not "tree-ish"), and
zero or more commit object names (not "committish");
- "git reset $rev" wants a committish; "git reset $rev -- $path"
wants a treeish.
They will come in later patches in the series.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add a field to setup_revision_opt structure and allow these callers
to tell the setup_revisions command parsing machinery that short SHA1
it encounters are meant to name committish.
This step does not go all the way to connect the setup_revisions()
to sha1_name.c yet.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Many callers know that the user meant to name a committish by
syntactical positions where the object name appears. Calling this
function allows the machinery to disambiguate shorter-than-unique
abbreviated object names between committish and others.
Note that this does NOT error out when the named object is not a
committish. It is merely to give a hint to the disambiguation
machinery.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We know that the token "$name" that appear in "$name^{commit}",
"$name^4", "$name~4" etc. can only name a committish (either a
commit or a tag that peels to a commit). Teach get_short_sha1() to
take advantage of that knowledge when disambiguating an abbreviated
SHA-1 given as an object name.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Teach get_describe_name() to pass the disambiguation hint down the
callchain to get_short_sha1().
Also add tests to show various syntactic elements that we could take
advantage of the object type information to help disambiguration of
abbreviated object names. Many of them are marked as broken, and
some of them will be fixed in later patches in this series.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
