Re: [PATCH 2/2] describe doc: remove '7-char' abbreviation reference
- Date: Sun, 7 Apr 2019 23:23:55 +0100
- From: Philip Oakley <philipoakley@xxxxxxx>
- Subject: Re: [PATCH 2/2] describe doc: remove '7-char' abbreviation reference
On 07/04/2019 21:05, Ævar Arnfjörð Bjarmason wrote:
I had had a look at most of the other '7 ' references and decided that
most of those I saw were about the minimum abbreviation settings, but it
looks like I maybe missed a few - like the gittutorials.
On Sat, Apr 06 2019, Philip Oakley wrote:
While the minimum is 7-char, the unambiguous length can be longer.
Signed-off-by: Philip Oakley <philipoakley@xxxxxxx>
noticed while looking int the Git-for-Windows patch thicket -
was looking for the ~n^m style!
Documentation/git-describe.txt | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/Documentation/git-describe.txt b/Documentation/git-describe.txt
index ccdc5f83d6..a88f6ae2c6 100644
@@ -139,7 +139,7 @@ at the end.
The number of additional commits is the number
of commits which would be displayed by "git log v1.0.4..parent".
-The hash suffix is "-g" + 7-char abbreviation for the tip commit
+The hash suffix is "-g" + unambiguous abbreviation for the tip commit
of parent (which was `2414721b194453f058079d897d13c4e377f92dc6`).
The "g" prefix stands for "git" and is used to allow describing the version of
a software depending on the SCM the software is managed with. This is useful
Both the old/new version are subtly wrong. Whether the new one is better
is another matter.
First, there's more places we mention the now-incorrect 7 characters, at
least these (one of which you're fixing). Found by grepping for ' 7 '
Documentation/git-branch.txt-182- Alter the sha1's minimum display length in the output listing.
Documentation/git-branch.txt:183: The default value is 7 and can be overridden by the `core.abbrev`
Documentation/git-branch.txt-184- config option.
Documentation/git-describe.txt:66: Instead of using the default 7 hexadecimal digits as the
Documentation/git-describe.txt-67- abbreviated object name, use <n> digits, or as many digits
Documentation/git-ls-tree.txt-93-Object size identified by <object> is given in bytes, and right-justified
Documentation/git-ls-tree.txt:94:with minimum width of 7 characters. Object size is given only for blobs
Documentation/git-ls-tree.txt-95-(file) entries; for other entries `-` character is used in place of size.
Documentation/gittutorial-2.txt:45:What are the 7 digits of hex that Git responded to the commit with?
Documentation/gittutorial-2.txt-52-name), and that the contents of a Git object will never change (since
Documentation/gittutorial-2.txt:53:that would change the object's name as well). The 7 char hex strings
Documentation/gittutorial-2.txt-54-here are simply the abbreviation of such 40 character long strings.
It was never correct that we'd pick 7 characters, we'd *try* that before
e6c587c733 ("abbrev: auto size the default abbreviation", 2016-09-30)
but would pick a longer one if it was unambiguous.
Whereas "unambiguous abbreviation" isn't correct either, and arguably
less correct. At least 7 is what we *still* pick as a fallback in lieu
of the auto-sizing, but just "unambiguous abbreviation" implies that in
a repo with some 10 objects we might show just one character, or that
we'd post-e6c587c733 pick say 7 characters in a repository where it *is*
unambiguous but where we've auto-sized to 12.
I've been meaning to follow-up on
where I among other things wanted to just have these instances all say
"commits will be abbreviated as described in XYZ in linkgit:<something>"
and summarize what happens there.
I don't mind if this goes in, I mainly wrote this E-Mail as a brain dump
since it jolted my memory on the topic, and so that I could dig it up
later & see how I intended to follow-up on those #leftoverbits
I was aware that I was being slightly economical with the truth, but
was just looking for a way of implying 'variable length' and I punted on
the long explanation as the particular reference was way down the
document. If anyone has a suggestion for a better phrase I'd be happy
And I could add it to the tutorials as well).
(added Junio, given his follow up email, though we still need a term for